Technologies Underlying Weapons of Mass Destruction - Anthrax ...

— — . — — .c ontents1 Introduction and Summary 1Nuclear Weapons 3Chemical Weapons, 6Biological Weapons 8Delivery Systems 112 Technical Aspects of Chemical WeaponProliferation 15Summary 16Acquiring a CW Capability 18Agents and Production Processes 21Indicators of CW Proliferation Activities 36Alternative Proliferation Pathways 53Append ix 2-A: Techniques for the Detectionand Analysis of Chemical Signatures 593 Technical Aspects of Biological WeaponProliferation 71summary 73Biological and Toxin Agents 76Acquiring a BTW Capability 82Indicators of BTW Agent Production 99Military Implications of Genetic Engineering 113vii

4 Technical Aspects of NuclearProliferation 119Overview and Findings 120Acquiring Nuclear Weapon Capability 127Sources of Nuclear Materials 129From Nuclear Materials to Nuclear Weapons 149Signatures of Nuclear Proliferation Activities 161Appendix 4-A: Components, Design,and Effects of Nuclear Weapons 173Appendix 4-B: Enrichment Technologies 176Appendix 4-C: Safeguards and the CivilianNuclear Fuel Cycle 181Appendix 4-D: Dual-Use Export Controls 1915 The Proliferation of Delivery Systemssummary 198Effectiveness of Delivery Systems 201Ballistic Missiles 207Combat Aircraft 235Cruise Missiles and Unmanned Aerial Vehicles244197Index 257. . .Vlll

8 I Technologies Underlying Weapons of Mass Destructionavailable. Unlike nuclear weapon facilities, whichgenerally exhibit fairly clear signatures, civilianchemical plants have multiple uses, are hundredsof times more numerous than nuclear facilities,and are configured in different ways dependingon the process involved. Moreover, many of thesame chemicals used to make chemical agents arealso used to make pharmaceuticals, pesticides,and other commercial products. Since manydifferent types of equipment are suitable forchemical agent production, plant equipment perse does not provide a reliable means of distinguishingbetween legitimate and illicit activities.Nevertheless, some potential signatures of chemicalweapon development and production exist,and a set of multiple indicators taken from manysources may be highly suggestive of a productioncapability.Indicators at suspect locations that may contributeto such an overall assessment include:visual signatures such as testing munitions anddelivery systems; distinctive aspects of plantdesign and layout, including the use of corrosionresistantmaterials and air-purification systems;presence of chemical agents, precursors, or degradationproducts in the facility’s production line orwaste stream; and biochemical evidence of chemicalagent exposure (including that due to accidentalleaks) in plant workers or in plants andanimals living in the vicinity of a suspect facility.Nevertheless, the utility of specific signaturesdepends on how a given weapon program operates,including the choice of production processand the extent of investment in emission-controltechnologies. Detection capabilities that are decisiveunder laboratory conditions may be ratherinconclusive in the field—particularly if theproliferant has been producing related legitimatechemicals (e.g., organophosphorus pesticides) inthe same facility and is willing to expend time,effort, and resources to mask, obscure, or otherwiseexplain away chemical agent productionactivities. Testing of chemical agents and trainingtroops in their use might be masked by experimentswith or training for the use of smokescreens. A robust inspection regime must thereforecomprise an interlocking web of inspections,declarations, notifications, and data fusion andanalysis, all of which a cheater must defeat inorder to conceal his violations. Focusing monitoringefforts at a single point-even one thought tobe a crucial chokepoint-would allow the cheaterto focus his efforts on defeating them.Keeping a production program covert forcesother tradeoffs. Some of the simplest productionpathways might have to be avoided since they useknown precursors or involve known productionprocesses. Purchasing equipment from multiplesuppliers to avoid detection, or jury-riggingfacilities from used equipment, might increasehazards to the workforce and nearby populations.BIOLOGICAL WEAPONSBiological-warfare agents are easier to producethan either nuclear materials or chemical-warfareagents because they require a much smaller andcheaper industrial infrastructure and because thenecessary technology and know-how is widelyavailable. Moreover, it would not be difficult tospread biological agents indiscriminately to producelarge numbers of casualties, although it ismuch more difficult to develop munitions thathave a predictable or controllable military effect.Agent and Weapon ProductionThe global biotechnology industry is informationintensiverather than capital-intensive. Much ofthe data relevant to producing biological agents iswidely available in the published literature andvirtually impossible for industrialized states towithhold from potential proliferants. A widespreadsupport infrastructure of equipment manufacturershas also arisen to serve the industry.Therefore, producing biological agents wouldbe relatively easy and inexpensive for anynation that has a modestly sophisticated pharmaceuticalindustry. Moreover, nearly all theequipment needed for large-scale production of

——Chapter I–Introduction and Summary 9A supply of standard biological agents forcovert sabotage or attacks against broad-areatargets would be relatively easy to produce anddisseminate using commercially available equipment,such as agricultural sprayers. In contrast,the integration of biological agents into precise,reliable, and effective delivery systems such asmissile warheads and cluster bombs poses complexengineering problems. Nevertheless, theUnited States had overcome these problems bythe 1960s and had stockpiled biological warfareagents.United Nations inspectors assessing the biologicalweapon potential of Iraqi fermenters and otherbioprocess equipment.pathogens and toxins is dual-use and widelyavailable on the international market.One technical hurdle to the production ofbiological weapons is ensuring adequate containmentand worker safety during agent productionand weapons handling, although the difficulty ofdoing so depends on the level of safety andenvironmental standards. A government thatplaced little value on the safety of plant workersor the civilian population might well take minimalprecautions, so that a biological-weaponsproduction facility would not necessarily beequipped with sophisticated high-containmentmeasures, Another challenge is ‘‘weaponizing’the agents for successful delivery. Since microbialpathogens and toxins are susceptible toenvironmental stresses such as heat, oxidation,and dessication, to be effective they must maintaintheir potency during weapon storage, delivery,and dissemination.Monitoring Biological Weapon ProductionDetection and monitoring of biological andtoxin agent production is a particularly challengingtask. Even use of biological weaponscould in some cases be difficult to verify unambiguously,since outbreaks of disease also takeplace naturally. Thanks to advances in biotechnology,including improved fermentation equipmentas well as genetic engineering techniques,biological and toxin agents could be made infacilities that are much smaller and less conspicuousthan in the past. Moreover, the extremepotency of such agents means that as little as a fewkilograms can be militarily significant. Sincelarge amounts of agent can be grown from afreeze-dried seed culture in a period of days toweeks, large stockpiles of agent are not required,although some stocks of the munitions to be filledwith these agents would be.There are no signatures that distinguish clearlybetween the development of offensive biologicalagents and work on defensive vaccines, sinceboth activities require the same basic know-howand laboratory techniques at the R&D stage.Moreover, almost all the equipment involved inbiological and toxin weapon development andproduction is dual-use and hence will not typicallyindicate weapons activity. Indeed, thecapacity to engage in illegal military activitiesis inherent in certain nominally civilian facilities.Some legitimate biological facilities can also

10 I Technologies Underlying Weapons of Mass Destructionconvert rapidly to the production of biologicalwarfare agents, depending on the degree ofsophistication of the plant and on the requiredscale of production, level of worker safety, andenvironmental containment. At the same time,however, legitimate applications of biological ortoxin agents (e.g., vaccine production and theclinical use of toxins) are relatively few atpresent. With the exception of a few vaccineproduction plants, such activities are largelyconfined to sophisticated biomedical facilities notnormally found in developing countries, andthese facilities generally do not engage in productionexcept on a small scale. Moreover, given thatthe global biotechnology industry is still in itsinfancy, the number of” legitimate activitiesfromwhich the illegitimate ones would have to bedistinguished-is still relatively small.Sensitive analytical techniques such as polymerasechain reaction {PCR) analysis or use ofmonoclinal antibodies can identify trace quantitiesof biological agents and might be able to doso even after the termination of illicit activities.However, the existence of such sensitive laboratorytechniques does not necessarily translate intoa negotiated verification regime that might beinstituted to monitor compliance with the BiologicalWeapons Convention, the international treatythat bans biological weapons. Other factors thatmust be assessed in establishing such a regimeinclude the likelihood of detecting clandestineproduction sites, the ability to distinguish prohibitedoffensive activities from permitted defensiveefforts, and the risk of divulging sensitive nationalsecurity or proprietary information duringinspections of U.S. facilities. 8Because of the difficulty of detecting clandestinebiological and toxin weapon developmentand production, effective tracking of such programswill require integrating data from manysources, with a particular emphasis on humanintelligence (agents, defectors, and whistleblowers).Some weaponization signatures (storageof bulk agents, preparation of aerosol dispensers,field testing, etc.) would probably be easier todetect than production signatures, but many suchsignatures could be concealed or masked bylegitimate activities such as biopesticide R&D oruse. Production and storage of components forBW munitions might also be masked by activitiesassociated with conventional weapons, such asproduction of high explosives, bomb casings, orartillery shells. Since excessive secrecy mightitself be indicative of offensive intent, greatertransparency would tend to build confidence in acountry’s lack of offensive intentions.Implications of New TechnologyGenetic engineering is unlikely to result in‘‘ supergerms’ significantly more lethal than thewide variety of potentially effective biologicalagents that already exist, nor is it likely toeliminate the fundamental uncertainties associatedwith the use of microbial pathogens inwarfare. However, gene-splicing techniques mightfacilitate weaponization by rendering microorganismsmore stable during dissemination (e.g.,resistant to high temperatures and ultravioletradiation). Biological agents might also be geneticallymodified to make them more difficult todetect by immunological means and insusceptibleto standard vaccines or antibiotics. At the sametime, genetic engineering techniques could beused to develop and produce protective vaccinesmore safely and rapidly.Cloning toxin genes in bacteria makes itpossible to produce formerly rare toxins inkilogram quantities. Moreover, molecular engineeringtechniques could lead to the developmentof more stable toxins. Even so, for the foreseeables The United States has already determined that inspection procedures under the Chemical Weapons Conventio% which allow the inspectedparty to negotiate the level of access to be provided to international inspectors, are sufficient to protect national security information and tradesecrets, However, it is not necessary the case that the same inspection procedures would be suitable for the Biological Weapons Conventionshould a formal veritlcation regime be instituted.

Chapter I-Introduction and Summary | 11future, toxin-warfare agents are unlikely to providedramatic military advantages over existingchemical weapons. It is possible that bioregulatorsand other natural body chemicals (or syntheticanalogues thereof) might be developed intopowerful incapacitants, but means of deliveringsuch agents in a militarily effective manner wouldfirst have to be devised. Moreover, if warning oftheir use were provided, chemical weapon protectivegear would blunt their impact.cz-nDELlVERY SYSTEMSAlthough military delivery systems such asballistic missiles, cruise missiles, and combataircraft are not essential to deliver weapons ofmass destruction, they can do so more rapidly,more controllably, and more reliably than rudimentarymeans such as suitcases, car bombs, orcivilian ships or planes. Controlling the spread ofadvanced delivery systems by no means wouldeliminate the dangers posed by weapons of massdestruction, particularly in terrorist applications.However, limiting the availability of these deliverysystems would make it harder for states to useweapons of mass destruction for military purposes,particularly against well-defended, forewarnedadversaries.Unlike nuclear, chemical, or biological weaponsthemselves, which are not traded openly dueto treaty constraints or international norms, deliverysystems such as aircraft and short-rangeantiship cruise missiles are widely available oninternational arms markets. Since the late 1980s,the United States and other Western industrializedcountries have had some success at delegitimizingthe sale of longer range ballistic andcruise missiles by creating the Missile TechnologyControl Regime (MTCR), the participants inwhich refrain from selling ballistic or cruisemissiles with ranges over 300 kilometers, or withany range if the seller has reason to believe thatthey may be used to carry weapons of massdestruction. However, missiles with ranges up to300 km-and to a lesser extent, up to 600-1,000United Nations inspector measuring an Iraqi Al-Husayn (modified Scud) missile in Baghdad.km-are already deployed in many Third-Worldcountries. Combat aircraft are possessed by almostall countries of proliferation concern. Cruisemissiles or other unmanned aerial vehicles withranges much over 100 km are not yet widespreadoutside the acknowledged nuclear weapon states,but large numbers of cruise missiles, includingantiship missiles, are available at lesser ranges.In terms of payloads that can be carried tospecfied ranges, the combat aircraft of virtuallyall countries of proliferation concern far surpasstheir missile capabilities. However, aircraft andmissiles have different relative strengths—particularly in their ability to penetrate defenses—and the two systems are not fully interchangeable.Piloted aircraft have significant advantages overother delivery systems in terms of range, payload,accuracy, damage-assessment capability, and dispersalof chemical or biological agents. They canbe used many times, usually even in the presenceof significant air defenses. Missiles, however, areharder to defend against, and they offer distinctadvantages for a country wishing to deliver asingle nuclear weapon to a heavily defended area.Since missiles are not restricted to operating fromairfields, they are also easier to hide fromopposing forces. The wide range of motivationsfor acquiring ballistic missiles-prestige, diversifyingone’s forces, their psychological value as

Chapter l-Introduction and Summary | 13launching ballistic missiles can be readily seen.Development of intermediate and long-rangeballistic missiles requires extensive flight testing,making it particularly noticeable. Although statespursuing both military and civil space technologymay wish to hide their military programs, civilianspace-launch programs are usually considered asource of national prestige and proudly advertised.Even a purely civilian space-launch programprovides technology and know-how useful forballistic missiles. The most important aspects ofa missile capability for weapons of mass destructionrangeand payload-can usually be inferred froma civil program. (A civil space-launch boosterdoes not need to have high accuracy, but neitherdoes a missile carrying weapons of mass destructionfor use against populations.) On the otherhand, certain attributes desired for military applications,such as reliable reentry vehicles, mobility,and ease of operation in the field, suggestdistinct technical approaches for military andcivil applications. Although solid-fueled boostersare in some ways more difficult to develop andbuild than liquid-fueled boosters, they are easierto use in mobile and time-urgent applications.Liquid-fueled boosters were the first used inmilitary applications and are still more common.(The seemingly ubiquitous Scud missile and itsmodifications, such as were launched by Iraqagainst targets in Israel and Saudi Arabia, areliquid-fueled.)Since combat aircraft are widely accepted asintegral to the military forces even of developingcountries, there is no reason to hide their existence.Individual planes, however, can be hidden.Moreover, modifications made to aircraft to carryweapons of mass destruction, or training given topilots for their delivery, might be difficult todetect without intrusive inspections.Of the three delivery systems, cruise missiledevelopment and testing will be the hardest todetect. Several types of unmanned aerial vehiclesare being developed and marketed for civilpurposes, and without inspection rights it will bedifficult to discern whether such vehicles havebeen converted to military purposes. Therefore,monitoring of delivery systems capable ofcarrying weapons of mass destruction willcontinue to be an uncertain exercise, havingmost success with missiles and highly capableaircraft. Nevertheless, the risk posed byother delivery systems cannot be dismissed.The full range of delivery technology must betaken into account when evaluating a country’soverall proliferation capabilities andbehavior.

———TechnicalAspectsof ChemicalWeaponProliferation 20f the three categories of weapons of mass destruction,chemical weapons are the most likely to be used inwarfare, and they remain a serious threat in regionalconflicts despite the end of the Cold War. Althoughwell-equipped troops can defend themselves against existingchemical agents with detectors, decontamination equipment, gasmasks, and protective garments (albeit at a some cost in militaryeffectiveness), chemical weapons can still have devastatingeffects when employed against defenseless civilians or poorlyequipped (or unprepared) armies or guerrilla fighters. This factwas starkly demonstrated during the 1980s by Iraq’s use ofchemical weapons against Iran and its own Kurdish population.The prospects for halting the proliferation of chemicalweapons are mixed. On the one hand, several states are currentlybelieved to possessor to be actively pursuing a chemical-warfare(CW) capability. On the other hand, the international communityrecently achieved a major step forward by concluding theChemical Weapons Convention (CWC) after more than twodecades of arduous negotiations. This treaty, which is expectedto enter into force in January 1995, enacts a comprehensiveglobal ban on the development, production, stockpiling, transferto other countries, and use of CW agents and delivery systems.The CWC also provides for a highly intrusive verification regimethat will provide a legal framework for enforcement. However,a number of key countries of concern have not yet signed thetreaty.This chapter describes the chief technical hurdles associatedwith the process of acquiring a militarily significant CWcapability and discusses detectable signatures’ associated witheach of these steps that might be used for monitoring orverification purposes. A separate report explains the tactical andstrategic uses of chemical weapons, and the extent andI 15

16 I Technologies Underlying Weapons of Mass Destructionconsequences of their spread. 1 The analysis herefocuses on mustard and nerve agents because theyare militarily the most effective and have beenweaponized and stockpiled by several countries.SUMMARYCW capabilities can vary greatly in sophistication.Although hundreds of tons of chemical agentwould be required for large-scale use in a majorconflict, smaller quantities could be effective fortactical engagements in regional wars or toterrorize population centers. An advanced CWcapability would entail production of severalagents with differing toxicities and physicalcharacteristics, mated to different types of munitions,but a crude CW arsenal might contain onlyone or two agents and a simple delivery systemsuch as an agricultural sprayer. The Iran-Iraq Warof the 1980s saw the first protracted use ofchemical weapons since World War I and the firstuse of nerve agents. According to Iranian sources,Iraqi chemical weapons accounted for some50,000 Iranian casualties, including about 5,000deaths. 2The growing availability of chemical knowhowand production equipment, combined withthe globalization of chemical trade, have givenmore than 100 countries the capability-if notnecessarily the intent-to) produce simple chemicalweapons such as phosgene, hydrogen cyanide,and sulfur mustard. A smaller number have thecapability to produce nerve agents such as GA(tabun), GB (sarin), GD (soman), and VX. Thereason is that whereas mustard-gas production isvery simple-particularly if thiodiglycol is availableas a starting material—making nerve agentsinvolves more complex and difficult reactionsteps. Technical hurdles associated with theproduction process include the cyanation reactionfor tabun and the alkylation reaction for the othernerve agents. Alkylation requires high temperaturesor highly corrosive reagents.Chemical plants capable of manufacturingorganic phosphorus pesticides or flame retardantscould be converted over a period of weeks to theproduction of CW agents, although this would notbe a simple process. Multipurpose plants wouldbe easier to convert than single-purpose plants.The hurdles to acquiring a CW production capabilityare lower if a proliferant country seeks onlyto produce low-quality agent for immediate useand is willing to cut comers on agent shelf-life,safety, and environmental protection. Even so,CW agent production is still several steps removedfrom an operational CW capability, whichalso requires the design andeffective munitions, the fillingbefore use, and mating with asystem.development ofof the munitionssuitable delivery| Indicators of CW Proliferation ActivitiesMany different types of precursor chemicalsand equipment, many of them dual-use, aresuitable for CW agent production. As a result,plant equipment or precursor chemicals per se donot provide a reliable means of distinguishingbetween legitimate and illicit production. Sincemost chemical facilities are relatively simple andmultiuse, nonproliferation policies will need tofocus on judgments of intent as well as capability.Detection of CW proliferation-either withinor outside the framework of an internationaltreaty regime requires the correlation of multipleindicators and intelligence sources, rangingfrom satellites to human defectors. The probabilityof detecting a clandestine CW capability musttherefore be evaluated in the context of the on-siteinspection regime established by the ChemicalWeapons Convention, as well as unilateral intelli-1U.S. Congress, Office of ‘IkcImology Assessment Proliferation of Weapons of Mass Destruction: Assessing the Risks, O’E4-ISC-559(Washingto4 DC: U.S. Government printing Office, August 1993).2Mike Eisenstadt, The Sword of the Arabs: Iraq’s Strategic Weapons, Washington Institute Policy Papers No. 21 (Washington DC:Washington Institute for Near East Policy, 1990), p, 6.

18 I Technologies Underlaying Weapons of Mass Destructionagents-consisting of two relatively nontoxicchemical components that when mixed togetherreact to form a lethal agent-might be attractiveto a proliferant because they are easier and saferto produce and handle, although they may bemore complex to use in combat.Each of the possible proliferation pathwaysinvolves tradeoffs among simplicity, speed, agentshelf-life, and visibility. The choice of pathwaywould therefore be affected by the urgency of acountry’s military requirement for a CW stockpile,its desire to keep the program secret, its levelof concern over worker safety and environmentalprotection, and the existence of embargoes onprecursor materials and production equipment.ACQUIRING A CW CAPABILITYAlthough hundreds of thousands of toxic chemicalshave been examined over the years for theirmilitary potential, only about 60 have been usedin warfare or stockpiled in quantity as chemicalweapons. 3 Physical properties required of CWagents include high toxicity, volatility or persistence(depending on the military mission), andstability during storage and dissemination. Lethalagents that have been produced and stockpiled inthe past include vesicants such as sulfur mustardand lewisite, which bum and blister the skin, eyes,respiratory tract, and lungs; choking agents suchas phosgene and chlorine, which irritate the eyesand respiratory tract; blood agents such as hydrogencyanide, which starve the tissues of oxygen;and nerve agents such as sarin and VX, whichinterfere with the transmission of nerve impulses,causing convulsions and death by respiratoryparalysis.Unlike nuclear weapons, which require alarge, specialized, and costly scientificindustrialbase, CW agents can be made withcommercial equipment generally available to. .Part of the U.S. Army’s Phosphate DevelopmentWorks, located on the grounds of Tennessee ValleyAuthority’s National Fertilizer Development Center inMuscle Shoals, Alabama. Between 1953 and 1957, thisfacility met the Army’s need for dichlor, a precursorneeded to produce the nerve agent sarin.any country. Indeed, few military technologieshave evolved as little as chemical weapons overthe past half-century. 4 Current-generation mustardand nerve agents are based on scientificdiscoveries made during and between the twoWorld Wars, and there have been few majorinnovations since then in either basic chemicalsor manufacturing methods. The vast majority ofthe U.S. stockpile (in terms of tonnage) wasproduced during the 1950s and 1960s, when theUnited States managed to produce high-qualityCW agents with what is now 30- to 40-year-oldtechnology. Moreover, production techniques forthe major CW agents have been published in theopen patent or chemical literature, including dataon reaction kinetics, catalysts, and operatingparameters. According to one analyst, “Theroutes of production are generally known, andthey can be pursued with relatively primitive3World Health Organization@ Health Aspects of Chem”cal and Biological Weapons: Report of a WHO Group of Consultants (GenevzWHO, 1970), p, 23,4In this respec~ there is a significant difference between manmade chemical agents and biological toxins, whose production has beentransformed by advances in biotechnology. See ch. 3.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation | 19equipment, especially by those who are not overlyconcerned with worker health and safety orenvironmental impacts.As the commercial chemical industry hasspread around the world in response to the urgentneeds of developing countries for chemical fertilizers,pesticides, and pharmaceuticals, the availabilityof chemicals and equipment required toproduce CW agents has increased. At the sametime, thousands of applied organic chemists andchemical engineers from developing countrieshave been trained in related production technologiesat universities in the United States, Europe,and the former Soviet Union. 6 According to RearAdm. Thomas A. Brooks, former Director ofNaval Intelligence:The substantial pool of Western or Westerntrainedscientists, engineers and technicians hassuccessfully been tapped for years by ThirdWorld states eager to acquire their expertise formissile development, nuclear, chemical and otherweapon projects. 7The dual-use nature of many chemical technologieshas made CW proliferation ‘‘an unfortunateside effect of a process that is otherwise beneficialand anyway impossible to stop: the diffusion ofcompetence in chemistry and chemical technologyfrom the rich to the poor parts of the world.Nevertheless, CW agent production is only onestep on the path to acquiring a full capability towage chemical warfare. A supertoxic agent,despite its lethality, does not become a usableweapon of war until it has been integrated withsome form of munition or delivery system andmade an integral component of a nation’s militaryplanning and doctrine.| Acquisition StepsThe following steps are required for a proliferantcountry seeking to acquire a fully integratedCW capability (see figure 2-l):1. acquire equipment and materials needed forCW agent production and the relevantexpertise;2. produce agents in small quantities at a pilotfacility to work out technical details of thesynthetic process, and then scale up to aproduction plant;3. purchase suitable munitions and deliverysystems (or design, prototype, test, andproduce them indigenously);4. fill the munitions with agent;5. establish bunkers (or other storage facilities)and logistical support networks for thestockpiling, transport, handling, and use ofbulk agents and munitions;6. deliver chemical munitions to the militarylogistics system for storage and transport tothe battle zone;7. acquire individual and collective chemicaldefenses and decontamination equipment,and train troops how to fight in a chemicalenvironment; and8. develop strategic and tactical battle plansfor CW use, and practice them in operationaltests and field exercises.To save time or money, a state seeking a morerudimentary CW capability might cut corners onsome of these steps, for example, by omittingrigorous safety and waste-treatment measuresduring the production process. Proliferant statesmight also settle for a less robust logisticalinfrastructure than that developed by the United5Kyle OISOQ “Disarmament and the Chemical Industry, ” Brad Roberts, cd., Chem”cal Disarmament and U.S. Secun’ty (Boulder, CO:Westview Press, 1992), p. 100.G In 1990, for example, foreigners accounted for a large fraction of full-time graduate students at U.S. universities studying chemistry (32percent) and chemical engineering (42 percent). Commission on Professionals in Science and ‘Ikchnology, “Foreign Graduate Students”(table), Scientific-Engineering-Technical Manpower Comments, vol. 29, No. 6, September 1992, p. 13.7Michael R. Gordon, ‘‘The Middle East’s Awful Arms Race: Greater Threats from Lesser Powers, ’ The New York Times, Apr. 8, 1990,sec. 4, p. 3.g Julian Pen-y Robinso~ “Chemical Weapons Proliferation: The Problem in Perspective, ” Trevor Findlay, cd., Chenu”cal Weapons andMissile Proliferation (Boulder, CO: Lynne Riemer, 1991), p. 26.

20 I Technologies Underlying Weapons of Mass DestructionR&DFigure 2-1-Chemicai M4apon AcquisitionSelect standard ordevelop novelagentsObtain precursorchemicalsEzzEtEiElClevelop andpilot-test>-r F Iproduction 17L processJ—wBinaryDesign, test, and build munitionsr Areadeliverv:Synthesize agentUnitary agentORMass-produceUse dedicated military .—plantORcomponents FYUse commercial plant —Storeagent1 I 1 ,J_7cluster bomb or warheadStockpile(unitary or binary) 1--- ‘ ---- “–> filledLI+Acquire delivery systemklAdai’i5H-— E ‘-’-L I 1Acquire operational capabilityEstablish‘UPW”4logistical~‘B ETrain =% troops to use CWmunitions and to fight Jin CW environment>--n1 OperationalcapabilitySOURCE: Office of Technology Assessment, 1993.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation 121States and other nations with a broad, integratedmilitary establishment. Finally, proliferants mightforego protection and decontamination capabilitiesif the opponent lacks a CW capability and thelosses resulting from “friendly free” are consideredan acceptable cost of war. 9AGENTS AND PRODUCTION PROCESSESI Sulfur MustardSulfur mustard (H), the main blistering agentused in warfare, is an oily liquid at roomtemperature that smells of garlic and ranges incolor from clear to dark brown depending onpurity. 10 It is readily absorbed by the skin andmost clothing. Sulfur mustard is fairly persistentin the environment, presenting a hazard for daysor even weeks depending on the weather. Comparedwith the more toxic nerve agents, sulfurmustard is relatively easy to produce and load intomunitions, and it can be stockpiled for decades—especially when distilled-either as bulk agent orin weaponized form. The primary drawbacks ofsulfur mustard as a CW agent are that:■■■it must be used in relatively high concentrationsto produce significant casualties;it freezes at a relatively high temperature—about 14 degrees Celsius (57 degrees Fahrenheit)for distilled mustard; andif not distilled to high purity, mustard tendsto polymerize when stored for long periods,forming solids that precipitate out of solutionand reduce the efficiency of dissemination.Sulfur mustard has diffuse toxic effects on thebody that may take as long as 3 hours or more tomanifest themselves. The primary effect of anattack with sulfur mustard is to produce painfulskin blistering and eye and lung irritation, resultingin a large number of wounded casualties whoplace an enormous burden on medical services.Heavy exposure to an aerosol of mustard ormustard vapor causes the lungs to fill with fluid,“drowning” the victim from within. 11 Nevertheless,only 2 to 3 percent of hospitalized Americanand British mustard casualties in World War Idied, and a similar low death rate was reported forIranian mustard casualties during the Iran-IraqWar. 12 Seven to 10 days after exposure, sulfurmustard can also cause a delayed impairment ofimmune function that increases vulnerability tobacterial infection and may lead to seriousmedical complications.PRODUCTION OF SULFUR MUSTARDNine production processes for sulfur mustardhave been documented in the published chemicalliterature. During World War I, thousands of tonsof mustard gas were produced from alcohol,bleaching powder, and sodium sulfite. DuringWorld War II, the two largest producers ofmustard gas, the United States and the SovietUnion, used two common industrial chemicalssulfurmonochloride and ethylene----as startingmaterials. 13 A mustard-gas plant based on thismethod could be located at an oil refinery, whichis an excellent source of ethylene and could alsoextract the necessary sulfur from petroleum ornatural gas. 14g U.S. Congress, OffIce of ‘lkchnology Assessment Who Goes There: Friend or Foe?, OTA-ISC-537 (Washington DC: U.S. Gov ernmentPrinting Offke, June 1993).10 StiW mus~d may be produced in either crude form (H) or washed and vacuum-distilled @).I I Most of tie w~fatiities cased by Irqi use of sulfur mustard during the Iran-Iraq War were caused by l@d on clothing ~%? tiedover a long period in the hot desert sun. William C. Dee, U.S. Army Chemical-Biological Defense Comman d, personal communication 1993.12 Seti Schonwdd, “Mustard Gas,” The PSR Quarterly, vol. 2, No. 2, June 1992, p. 93.13 Gordon Burck et al., Chenu”cal Weapons Process Parameters, Vol. I: Main Report (Alexandria VA: W COT., Repofi No.DNA-TR-91-217-V1, November 1992).14 Gordon M. Buck and ~les C. Flowerree, International Handbook on Chem”cal Weapons prOlifeWiO?I (New yOr& NY: m~nwodPress, 1991), p. 50.

22 I Technologies Underlying Weapons of Mass DestructionToday, the precursor of choice for any large-fscale production of mustard gas is thiodiglycol, ac z0sulfur-containing organic solvent that has com-pmercial applications in the production of ball- %point pen inks, lubricant additives, plastics, andz cmphotographic developing solutions, and as acarrier for dyes in the textile industry. Thiodigly -CO1 is just one step away from production of sulfurmustard, requiring only a reaction with a chlorinatingagent like hydrochloric acid (HC1), a widelyavailable industrial chemical. 15 (See figure 2-2.)Known as the Victor Meyer-Clarke Process, thechlorination of thiodiglycol was developed byGermany during World War I and adopted in the1980s by Iraq. It does not require a particularlysophisticated chemical industry and could, indeed,be performed in a basement laboratory withthe necessary safety precautions.Sulfur mustard can be produced on an industrialscale on either a batch or continuous basis.Plant that produces the “dual-use” chemicalthiodiglycol, which is both a key ingredient ofGiven the extreme corrosiveness of hot hydro-ballpoint pen ink and an immediate . precursor of .chloric acid, it is advisable-but not essential-to mustard agent.Figure 2-2—Production of Sulfur MustardCH 2=CH 2(ethylene)CH 2CH 2-OHCH 2CH 2CI+ //2 C H 2-CH 2+ H 2S ~ S +2 HCI - S +2 H 2O\ o/ \, \CH 2CH 2-OHCH 2CH 2CIEthylene Hydrogen Thiodiglycol Sulfur mustard (H)oxidesulfideSOURCE: Stephen Black, “Vesicant Production Chemistry,” In Black, Benoit Morel, and Peter Zapf, Tdnka/Aspectsof Verifimtion of the Chernid Weapons Convention, Internal Technical Reprt, Carnegie-Mellon Program onInternational Peace and Security, 1991, p. 56.15 See Ronald G. Sutherland, “’I’hiodiglycol, “ in S. J. Lundh cd,, Verification of Dual-Use Chemicals Under the Chendcal WeaponsConvention; The Case of Thiodiglycol, SIPRI Chemical & Biological Warfare Series No. 13 (Oxford, England: Oxford University Press,1991), pp. 24-30,

Chapter 2–Technical Aspects of Chemical Weapon Proliferation | 23use corrosion-resistant reactors and pipes. Thisrequirement might be reduced by substituting aless corrosive chlorinating agent for HC1 or byreplacing the production equipment as often asnecessary. In order to improve the purity andstability of sulfur mustard in storage, corrosivebyproducts can be removed by distillation orsolvent extraction.There are five U.S. producers of thiodiglycoland about eight foreign producers in five countries.l6 Most of these companies do not sell thechemical but use it internally in the manufactureof other products. In addition, about 100 firmsworldwide purchase thiodiglycol for the synthesisof specialty chemicals and other industrial uses. 17When Iraq began mustard-gas production in theearly 1980s, it was unable to make thiodiglycolindigenously and ordered more than 1,000 tonsfrom foreign sources.18 In response to the threatenedembargo on exports of thiodiglycol fromWestern countries, however, Iraq developed anindigenous production capability based on reactingethylene oxide with hydrogen sulfide. Both ofthese ingredients are widely available. Hydrogensulfide can be extracted from natural gas or crudeoil, where it is often present as an impurity, orderived from elemental sulfur. Ethylene oxide isreadily produced from ethylene, a major productof petroleum refining.In sum, the production of mustard gas isrelatively easy from a technical standpoint andcould probably be concealed. While exportcontrols on thiodiglycol might initially create amajor hurdle for new proliferants, the effectivenessof controls will diminish as these countriesacquire an indigenous capability to produce it.Furthermore, just because synthesis from thiodiglycolis the ‘‘best’ process does not mean that itwill be used by a proliferant. Any of the othersynthetic pathways could work just as well for adeveloping country and might be used to circumventexport controls.| Nerve AgentsNerve agents are supertoxic compounds thatproduce convulsions and rapid death by inactivatingan enzyme (acetylcholinesterase) that isessential for the normal transmission of nerveimpulses. The nerve agents belong to the class oforganophosphorus chemicals, which contain aphosphorus atom surrounded by four chemicalgroups, one of which is a double-bonded oxygen.Although many organophosphorus compoundsare highly toxic, only a few have physicalproperties that give them military utility as nerveagents. 19 The difference in toxicity betweenpesticides and nerve agents derives from thenature of the chemical groups surrounding thephosphorus atom. In general, nerve agents are 100to 1,000 times more poisonous than organophosphoruspesticides. 20Two classes of nerve agents, designated G andV agents, were produced in large quantities in the1950s and ’60s by the United States and theformer Soviet Union. (See figure 2-3.)The G-series nerve agents are known both byinformal names and military code-names: tabun(GA), sarin (GB), GC, soman (GD), GE, and GF.This class of compounds was discovered in 1936by Gerhard Schrader of the German firm IG16 h. ~f(el, personal cornmunkatioq 1992; U.S. Department of Commerce, Bureau of ExpOfl ~‘ “stratiom Office of ForeignAvailability, Foreign Availability Review: 50 CW Precursor Chemicals (II) (Washingto& DC: Department of Commerce, Nov. 8, 1991), p.54.17 Giovanni A. Snidle, ‘ ‘United States Efforts in Curbfi]g Chemical Weapons Proliferation, ’ World Military Expenditures and ArmIYamfers 1989 (Washington, DC: U.S. Arms Control and Dis armament Agency, October 1990), p. 23.18 W. Seth G-w,, The Gem’e Unleashed: Iraq’s Chemical and BioZogicai Weapons Program, policy papers No. 14 (wmtigtOn, ~: TheWashington Institute for Near East Policy, 1989), p. 13.1$’ Benj~in Wltten, The ,$earch for Chemica/ Agents (Aberdee~ MD: Edgewood Arsenal Special Tectical Repom 1969).20 Alan R. Pittaway, “The Difficulty of Converting Pesticide Plants to CW Nerve Agent Manufacture, ” Task IV, Technical Report No. 7(Kansas City, MC): Midwest Research Institute, Feb. 20, 1970), p. 1.

I24 I Technologies Underlying Weapons of Mass DestructionCH 3Figure 2-3-Nerve AgentsTabun (GA)o\ ) – c~: N/NCH 3OCH 2CH 3Sarin (GB)o CH 3IICH.— P — o — ’ b — - HIF CH 3Soman (GD)CH 3Io C H 3—– C — CH 3II o – ~C H 3— P — — — - HIF CH 3VXoIICH 3—-C -----CH 3C H 3— — — CH 2CH 2—- N7sOCH 2CH 3C H 3—- C — CH 3SOURCE: JAYCOR, Noncompliamx Scenarios: Means By WhkAParties to the Chemical Weapons Convention Might Cheat TechnicalReport No. DNA-TR-91-193, January 1993, pp. B-2-B-5.Farben during research on new pesticides. Althoughtabun is relatively easy to produce, it is notas toxic as the other G agents. After World WarII, details of German research on the G agentswere published, and sarin and soman emerged aspreferred agents for military purposes.All the various G agents act rapidly andproduce casualties by inhalation, although theyalso penetrate the skin or eyes at high dosesHH(particularly when evaporation is minimized andcontact is prolonged by contamination of clothing).21Sarin evaporates faster than it penetratesthe skin, but soman and GF are less volatile andpose more of a skin-contact hazard.The V-series nerve agents include VE, VM,and VX, although only VX was weaponized bythe United States. These agents were originallydiscovered in 1948 by British scientists engagedin research on new pesticides. Military developmentwas then conducted by the United States andthe Soviet Union, both of which began large-scaleproduction of V agents in the 1960s. 22 VX is anoily liquid that may persist for weeks or longer inthe environment. Although not volatile enough topose a major inhalation hazard, it is readilyabsorbed through the skin. The lethal dose of VXon bare skin is about 10 milligrams for a 70kilogram man. 23PRODUCTION OF NERVE AGENTSFrom the standpoint of production processes,the nerve agents can be clustered into threegroups: tabun; sarin/soman, and VX.TabunThe first militarized nerve agent and thesimplest to produce, tabun (GA), is made fromfour precursor chemicals: phosphorus oxychloride(P0C1 3), sodium cyanide, dimethylamine,and ethyl alcohol. Most of these ingredients arewidely available. Ethanol and sodium cyanide arecommodity chemicals that are manufactured andsold in vast quantities; dimethylamine and phosphorusoxychloride are produced by companies inseveral countries for commercial applications inthe production of pharmaceuticals, pesticides,missile fuels, and gasoline additives.21 COI. M,ic~el A. ~ arid Fr~~ck R. Sidell, “Progress in Medical Defense Against Nerve Agents, ” Journulof ihe American MedicalAssociation, vol. 262, No. 5, Aug. 4, 1989, p. 649.22 Wuel sanches et al., Chemical Weapons Convention (CWC) Signatures Analysis (AdingtOIL VA: system pl- g Corp., FinalTkdm.ical Report No. 1396, August 1991), p. 68.23 Witten, op. cit., footnote 19, pp. 92, IW.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation 125The basic production process for tabun wasdeveloped by Germany during World War II andwas later employed by Saddam Hussein’s Iraq.Tabun synthesis does not require the use ofcorrosive starting materials and does not producehighly reactive intermediates. The two-step processinvolves mixing the ingredients and a carriersolvent in a reaction vessel equipped with asodium-hydroxide scrubbing system to neutralizethe gaseous hydrochloric acid (HC1) byproduct. Arelatively simple air-tight enclosure is also neededto prevent the escape of toxic vapors. Theingredients must be added in the correct order,without heating, and the vessel cooled to keep thereaction from building up too much heat. Little orno distillation equipment is required, although thepurity of tabun can be increased to more than 80percent by removing the carrier solvent and theoff-gasses by vacuum distillation. 24 In sum, tabunproduction is relatively easy because it does notinclude the difficult alkylation reaction needed tomake the other nerve agents. The major technicalhurdle in tabun synthesis is the cyanationreaction (in which a cyanide group is added tothe central phosphorus), because of the difficultyof containing the toxic hydrogen cyanideHCN gas used as the reagent.During World War II, Germany manufacturedtabun in large quantities but never used it incombat. In early 1940, the Germans beganconstruction of a huge tabun factory with thecapacity to produce 3,000 tons of agent a month.Because of technical problems, however, it tookthe Germans over 2 years, until April 1942, to getthe plant operational. 25 The Iraqis also haddifficulties with the manufacture of tabun, althoughthey managed to produce a material withabout 40 percent purity that was used in theIran-Iraq War. 26Sarin/somanSarin (GB) and soman (GD) are both made ina batch process with the same basic reaction steps,but they contain different alcohol ingredients:isopropyl alcohol for sarin and pinacolyl alcoholfor soman. (The choice of alcohol changes thetoxicity and volatility of the product but does notaffect the difficulty of production.) Phosphorustrichloride (PCl 3) is the basic starting material forthe synthesis of both agents and, depending onwhich of several alternative synthetic pathways ischosen, two to five steps are required to make thefinal product. The alternative syntheses all involvethe same four reaction steps, which can becarried out in several different sequences. 27 Duringthe 1950s, new production methods overcamethe technical difficulties that had prevented theGermans from engaging in the large-scale productionof sarin and soman during World War II.The introduction of these new methods enabledthe U.S. sarin plant at Rocky Mountain Arsenal inColorado to produce 10 tons of agent per day.The synthesis of G agents entails three majortechnical hurdles. First, the production processinvolves the use of hot hydrochloric acid (HC1)and hydrogen fluoride (HF), both of which areextremely corrosive. The use of these compoundsin reactors and pipes made of conventional steel~ S. Bkck, B. lvfoRl, and P, Zapf, “Veri.tlcation of the Chemical Convention” Nature, vol., 351, June 13, 1991, p. 516.2s ROM- and Jeremy PaxrnmL A Higher Form of Killing: The Secret Story of Germ and Gas Wa~are (1-ondon: Chatto & Windus,1982), pp. 55-56.26 DCC, op. cit., footnote 11.27 For ~-plc, the u~t~ s~tti ~s~ tie s~~led “Di.Di” process to ~oducc sfi. ~ ~s proc~s, rnethylphosphonic dichlotidc ~),or CH#OCt, is partially reacted with hydrogen fluoride (I-IF) gas to make a roughly 50:50 mixture of DC and methylphosphonic dilluoride(D~. The DC-DF mixture is then reacted with isopropyl alcohol. This reaction displaces chlorine atoms preferentially, resulting in theformation of sarin and hydrochloric acid @iCl) gas, which must be removed rapidly by distillation to avoid degradation of the nexve-agentproduct. (Pure DF is not used because the reaction with isopropyl alcohol would liberate HF gas, which is soluble in G agent and virtuallyimpossible to degas, resulting in a highly corrosive mixture.)

26 I Technologies Underlying Weapons of Mass Destructionresults in corrosion measured in inches per year. 28During World War II, the Germans lined theirreactors with silver, which is resistant to HCl andHF. Today, corrosion-resistant reaction vesselsand pipes are made of alloys containing 40percent nickel, such as the commercial productsMonel and Hastalloy. 29 Although it is possible tomanufacture sarin and soman without corrosionresistantreactors and pipes, the chance of majorleaks is significantly increased compared withusing corrosion-resistant equipment.The second hurdle in the production of Gagents is the alkylation reaction, in which amethyl group (-CH 3) or an ethyl group (-CH 2CH 3)is added to the central phosphorus to form a P-Cbond. This step is rarely used in the production ofcommercial pesticides and is technically difficult.The third hurdle is that if high-purity agentwith a long shelf-life is required, the supertoxicfinal product must be distilled-an extremelyhazardous operation. Distillation is not necessaryif a country plans to produce nerve agents forimmediate use rather than stockpiling them.During the Iran-Iraq War, for example, Iraq gavepriority to speed, volume, and low cost ofproduction over agent quality and shelf-life. As aresult, the sarin in Iraqi chemical munitions wasonly about 60 to 65 percent pure to begin with andcontained large quantities of hydrogen fluoride(HF), both because of the synthesis process usedand the deliberate omission of the distillationstep. Although the Iraqis could have distilled theirsarin to remove the excess HF, they chose not todo so because the batches of agent were intendedto be used within a few days. To retard the rate ofdeterioration, sarin-filled shells were stored inrefrigerated igloos. Thus, whereas the distilledsarin produced by the United States in the early1960s has retained a purity of more than 90percent for three decades, the agent content ofIraqi sarin after 2 years of storage had generallydegraded to less than 10 percent and in some casesbelow 1 percent. 30VXThe persistent nerve agent VX has a phosphorusmethyl(P-CH 3) bond and a phosphorus-sulfurbond but contains no fluorine. There are at leastthree practical routes to V-agents that might beused by proliferant countries. As with G agents,production of VX involves a difficult alkylationstep. 31 Because the VX manufacturing processavoids the use of HF gas, however, it is lesscorrosive than the production of sarin and soman.Indeed, after the alkylation step has been completed,the rest of the synthesis is straightforward.PRODUCTION HURDLESIn summary, the technologies required for theproduction of mustard and nerve agents have beenknown for more than 40 years and are within thecapabilities of any moderately advanced chemicalor pharmaceutical industry. The technical hurdlesassociated with nerve-agent production are notfundamentally different from those associatedwith commercial products such as organophosphoruspesticides. The most technically challengingaspects include:■ the cyanation reaction for tabun, whichinvolves the containment of a highly toxicgas;28 Stephen Blx~ Benoit Mon:l, ~d peter Zapf, Technical Aspects of the Chemical Weapons Convena”on: rnte~”m Technical Report(Pittsburgh, PA: Carnegie Mellon University, Program on International Peace and Seeurity, 1991), p. 70.29 AIfiou@ g~s-lined reactors and pipes resist HC1 corrosio~ H@ attacks glass and hence can only be used h meti remtors.n United Nations Special commission, “Second Report by the Executive Chairman of the Special Commission Established by theSecretary-General Pursuant to Paragraph 9 (b) (i) of Security Council Resolution 687 (1991 ),” UN Security Council document No. S/23268,Dec. 4, 1991, p. 5.31 me U.S. p~duction rnetiod for VX, known as the Newport process, involved high-temperature rnet.hylatio~ in wtich phosphorustrichlonde (PC13) is reacted with mlethane gas (CH~ at a high temperature (500 degrees C) to form au alkylated intermediate, with a yield ofonly about 15 percent,

Chapter 2–Technical Aspects of Chemical Weapon Proliferation! 27the alkylation step for sarin, soman, and VX,which requires the use of high temperaturesand results in corrosive and dangerous byproductssuch as hot hydrochloric acid;careful temperature control, including coolingof the reactor vessel during heatproducingreactions, and heating to completereactions or to remove unwanted byproducts;intermediates that react explosively withwater, requiring the use of heat-exchangersbased on fluids or oils rather than water; anda distillation step if high-purity agent isrequired.While some steps in the production of nerveagents are difficult and hazardous, they wouldprobably represent more of a nuisance than a trueobstacle to a determined proliferant. The finaldistillation step can also be avoided if a proliferantcountry seeks to manufacture low-purityagent for immediate use and is prepared to cutcorners on safety, environmental protection, andthe life-span of the production equipment. Indeed,the United States produced nerve agents veryeffectively with 1950s technology and withoutthe stringent safety and environmental standardsthat would be required today. In an attempt toconceal a CW production effort, a proliferantcountry might also resort to less-well-knownproduction processes that had earlier been discardedbecause of their high cost, inefficiency,hazards, or need for unusual precursors or cata-lysts.costsA sulfur-mustard production plant with airhandlingcapabilities might cost between $5million and $10 million to build, In contrast, amore sophisticated G-agent production facilitywould cost between $30 and $50 million. Sincewaste-handling facilities would account for morethan 50 percent of the cost of a G-agent plant, a‘‘no-frills’ production facility that did away withwaste handling might cost about $20 million. 32Construction of a large-scale plant and equipmentwould be almost impossible for a developingcountry without outside assistance, but cost aloneis unlikely to be the deciding factor for adetermined proliferant.| Implications of New TechnologyGiven the well-understood production pathwaysof mustard and nerve agents and their recordof use in warfare, a developing country thatsought to acquire a CW capability would not needto develop and weaponize new agents. Thedevelopment and production of novel CW agentswould probably be undertaken only by nationswith an advanced scientific-industrial base; eventhen, a major investment of time and resourceswould be required. During the 1930s, it took anadvanced industrial country like Germany 6 yearsto put the first nerve agent, tabun, into production.33Even so, the development of entirely newclasses of CW agents remains a real possibility. Inlate 1992, a Russian chemist alleged that amilitary research institute in Moscow had developeda new binary nerve agent more potent thanVX; he was subsequently arrested by the RussianSecurity Service for disclosing state secrets. 34Another cause for concern is that some laboratoriesworking on chemical defenses are studyingthe mode of action of nerve agents at themolecular level. Although the purpose of thisresearch is to develop more effective antidotes, itcould also assist in the development of novel32 I)&, op. Cl(,, fOO~O[e 11.33 Gordon M. Bm&, “chemical weapons Production Ikchnology and the Conversion of Civil PHXhCtiOIL” Arm Confiol, VO1. 11, No.2, September 1990, p. 145.34 *~-yaov, Fedor~v De~l Russi~ CW ~odu~tio~’ No~oye Vremya (Moscow), No. 44, October 1992, pp. 4-9 (translated illFBIS-SOV-92-213, Nov. 3, 1992, pp. 2-7). See also, Will Englund, ‘‘Ex-Soviet Scientist Says Gorbachev’s Regime Created New Nerve Gasin ‘91,” Baltimore Sun, Sept. 16, 1992, p. 3.

28 I Technologies Underlying Weapons of Mass Destructioncompounds more deadly than existing nerveagents. 35 A more potent agent would not necessarilytranslate into greater military effectiveness,however, unless the dissemination system wereimproved as well.Some experts are also concerned that eventhough the Chemical Weapons Convention (CWC)bans the development of any toxic chemical forwarfare purposes, some countries might seek tocircumvent the CWC verification regime bymodifying existing agents to avoid detection orby weaponizing a “second string” of known butless effective poisons. The carbamates, for example,are a class of toxic pesticides that resembleorganophosphorus nerve agents in that theyinactivate the enzyme acetylcholinesterase. Todate, the carbamates have not been developed asCW agents because they have a number ofoperational drawbacks: they are relatively unstable,are solids at room temperature (posing less ofan inhalation threat), and are relatively easy totreat or pretreat with antidotes. 36 Even so, suchchemicals might become more attractive as analternative to standard nerve agents. Also ofpotential concern as novel CW agents are toxinsof biological origin, which might be produced inmilitarily significant quantities with biotechnologicaltechniques. Some toxins are thousands oftimes more potent than nerve agents, althoughthey also have operational limitations. (See nextchapter.)Another potential threat is the use of penetrantchemicals to defeat chemical defenses, such as“mask-breakers’ capable of saturating gas-maskfilters made of activated charcoal. 37 Defensiveequipment has long been modified to deal withcertain small molecules of this type and is stillbeing improved. 38 Although a variety of othermeans for penetrating masks and protectiveclothing have been examined over a period ofmany years, all of them have operational shortcomings.39 Even so, penetrants remain a seriouspotential threat. If a new concept for penetratingCW defenses emerged that lacked theexisting drawbacks, it could have a majorimpact on the overall military significance ofchemical weapons. As one analyst has pointedout, the long-term danger is that “some futuretechnological development might reverse thepresent ascendancy of the defense (i.e., antichemicalprotection) over the offense, thereby destroyinga major incentive for deproliferation. " 40Since such a technological breakthrough couldtrigger renewed competition in chemical weapons,measures to constrain research and developmentwould be of major value in halting CWproliferation.| Precursor Chemicals for CW AgentsChemicals that serve as starting materials in thesynthesis of CW agents are known as ‘ ‘precursors.During the two world wars, the majorpowers produced CW agents from indigenousprecursors. In World War I, for example, Germanymanufactured chlorine and phosgene gas inhuge volumes with existing chemical facilities.35 fite~Aff& ~d ~te~io~T~e cm@ vefilcationRc~ hUnic Ven~cation Methodr, Handling, andAssessment of UnusualEvents in Relation to Allegations of the Use ofNovel Chemical Warfare Agents (Ottaw% Canada: External Affairs, March 1990), p. 10.~ ~em k, however, mother side to the coin. The reversibility of carbamate poisordng (e.g., Wih mophe treatment) would offer anadvantage to the attacker in the case of accidental leaks or spills. Similarly, the relative instability of carbamates wotid result in less persistencein the environment facilitating occupation of attacked territory.37 Walter J. Stoessel, Jr., chairman, et al,, Report of the Chemical Wa&areReview Commission (WaaMngtou DC: U.S. Government ~mOfXce, June 1985), p, 32.38 ‘Ikk@one interview with Tom Daahie~ conaultan~ U.S. Arms Control md Dk~ ent Agency, Feb. 9, 1993.39 J. PerryRob~m C& The C’he~”calIndus~ andthe Projected Chemical Weapons Convention, Vol. Z: Proceedings of a SIPRIIPugwashConference (New Yo~ NY: Oxford University Press, 1986), p. 70.a J~~ Peny Robtioq “The Supply-Side Control of the Spread of Chemical Weapons,” Jean-Francois Rio% cd., L“nu”ting theProliferation of Weapons: The Role of Supply-Side Strategies (Ottaw4 Canada: Carleton Univexxity Press, 1992), p. 70.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation! 29Table 2-l—Dual-Use ChemicalsDual-use chemical CW agent Commercial productThiodiglycol Sulfur mustard Plastics, dyes, inksThionyl chloride Sulfur mustard PesticidesSodium sulfide Sulfur mustard PaperPhosphorus oxychloride Tabun InsecticidesDimethylamine Tabun DetergentsSodium cyanide Tabun Dyes, pigments,gold recoveryDimethyl methylphosphonate G Agents Fire retardantsDimethyl hydrochloride G Agents PharmaceuticalsPotassium bifluoride G Agents CeramicsDiethyl phosphite G Agents Paint solventSOURCE: Giovanni A. Snidle, “United States Efforta in Curbing Chemical Weapons Proliferation,” U.S. Arms Controland Disarmament Ageney, l%dcfkfilitary Expenditures andArms Transfers 7939 (Washington, DC: U.S. GovernmentPrinting Office, October 1990), p. 23.Today, however, the globalization of the chemicalindustry has led to large international flows ofdual-use chemicals.Many of the basic feedstock chemicals used inthe production of nerve agents (e.g., ammonia,ethanol, isopropanol, sodium cyanide, yellowphosphorus, sulfur monochloride, hydrogen fluoride,and sulfur) are commodity chemicals that areused in commercial industry at the level ofmillions of tons per year and hence are impossibleto control. Monitoring their sale would also be oflittle intelligence value because the imprecisionof international-trade data would make it impracticalto detect the diversion of militarily significantquantities. Hydrogen fluoride, for example,is used at many oil refineries and can be purchasedcommercially in large quantities; it is alsoeasily derived from phosphate deposits, whichusually contain fluorides.Most of the key precursors for nerve-agentproduction also have legitimate industrial uses,but the fact that they are manufactured inmuch smaller volumes makes them somewhateasier to control These chemicals include phosphorustrichloride (with 40 producers worldwide),trimethyl phosphite (21 producers), and—for tabun only—phosphorus oxychloride (40producers). 41 phosphorus oxychloride, for example,is used extensively in commercial productssuch as hydraulic fluids, insecticides, flameretardants, plastics, and silicon. Similarly, dimethylmethylphosphonate (DMMP), an intermediatein nerve-agent production, is produced as aflame retardant by 11 companies in the UnitedStates and 3 in Europe (Belgium, United Kingdom,and Switzerland) .42 (See table 2-l.)Developing countries seeking a CW capabilitygenerally lack the ability to manufacturekey precursor chemicals and must purchasethem from foreign sources, typically at wellabove normal market rates. Because of thisdependency, Western governments have attemptedto slow CW proliferation by establishing acommittee known as the Australia Group, whichcoordinates national export-control regulations torestrict the sale of key CW precursors to sus-41 U.S. D~ment of Commerce, op. cit., footnote 16, pp. 39, 58, 36, resp=t.ively.42 bid., pp. 22-23. Lists of souc~ of Cw precursors VW, since some lists include only those companies with an a.nnud prtiuction volumegreater than 4,500 kilograms or 5,000 pounds.

30 I Technologies Underlying Weapons of Mass Destructionpected proliferants. 43 Nevertheless, the exportcontrols coordinated by the Australia Groupcannot prevent countries that are outside thisbody from selling precursor chemicals. Indeed, asWestern countries have tightened CW-relatedcontrols, exports from developing nations such asIndia have increased. Of the 54 precursor chemicalswhose exports are regulated by the AustraliaGroup countries, Indian companies export about15, only 4 of which are subject to Indiangovernment export controls. 44Furthermore, to the extent that immediateprecursors for mustard and nerve agents arecontrolled by the Australia Group, a proliferantmight seek to circumvent such export controls inthe following ways:Substituting an uncontrolled precursorchemical for one that is controlled. Forexample, although thionyl chloride is subjectto export controls as a chlorinating agent forproducing nerve agents, a proliferant couldeasily substitute some other chlorinatingagent (e.g., phosgene, sulphuryl chloride)that is not on any export-control list. Thus,the technical means may exist to bypass anyparticular technology-transfer barrier. 45Purchasing relatively small amounts ofthe same or different precursor chemicalsfrom multiple sources, instead ofobtaining large quantities from a singlesource. For example, a country might purchaseseveral different types of chlorinatingagent for the conversion of thiodiglycol tosulfur mustard. Such a purchasing strategywould reduce the visibility of CW production,although it would also increase thecomplexity of the production process.Producing more obscure (but still effective)CW agents whose precursors arestill available. For example, production ofthe nerve agent soman (GD) requires pinacolylalcohol, which has no commercial usesand whose export is restricted by the AustraliaGroup. Because of this embargo, Iraqimilitary chemists chose instead to produce a60:40 mixture of sax-in and GF (a lesscommon nerve agent of intermediate persistence).46 Sarin is made with isopropyl alcohol(ordinary rubbing alcohol), while GF ismade with cyclohexyl alcohol (an industrialdecreasing agent). Unlike pinacolyl alcohol,both isopropyl alcohol and cyclohexyl alcoholare common industrial chemicals that arenot subject to export controls.“Back-integrating,” or acquiring an indigenouscapability to manufacture precursorchemicals from simpler compoundswhose export is not controlled or that areavailable from domestic sources. For example,thiodiglycol, the immediate precursorof sulfur mustard, can be produced in abatch process by reacting ethylene oxidewith hydrogen sulfide. Both of these ingredientscan be derived from oil or natural gas.Before the Persian Gulf War, Iraq built ahuge production line at its Basra petrochemicalscomplex that was capable of manufacturing110,000 tons of ethylene per year. 47In the case of nerve agents, all of the keyprecursors can be made from the most basicstarting materials; including phosphorus, chlorine,and fluorine. The production facilitiesneeded to make these precursors from raw materialsare not particularly large and could be43 Jfi~ Pq Robinsont “’I%e Australia Group: A Description and Assessmen~” Hans Guenter Brauch et al., eds., Controlling theDevelopment and Spread of Milita~ Technology (Amsterdam: W University Press, 1992), pp. 157-176.44 ~c~el R. GordoU “U.S. Accuses India on Chemical Arms,” New York Times, Sept. 21, 1992, p. A7.45 Rob~oq “me supply-side coxlml of the Spread of ~emktd WeaPOrlS, ” op. ci~, foo~oti ~, P. 68.46 U.S. Dep-at of D~eme, The Conduct of the Persian Gulf War: Final Report to Congress (Washingto% ~: Depmtment of Wfense,Ap~ 1992), p. 18.47 Kenne~ R. T~rne~, Th,? Death Lobby: How the West Armed Iraq (Boston: Houghton-M.ifflh 1991), p. 35.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation I 31embedded in an existing industrial complex,although large amounts of energy would berequired. During the Iran-Iraq War, for example,the Australia Group made a concerted effort toprevent Iraq from obtaining supplies of phosphorusoxychloride (POCl 3), a key precursor oftabun. In response, Baghdad built a plant tomanufacture phosphorus oxychloride indigenously,using raw phosphate ore from its huge phosphatemine at Akashat, so that it was no longervulnerable to supplier embargoes of this precursor.48Iraq also tried to apply back-integration to sarinproduction. In 1988, the Iraqi government contractedtwo West German companies to buildthree chemical plants at Al Fallujah, 60 mileswest of Baghdad, for the conversion of elementalphosphorus and chlorine into phosphorus trichloride(PCl 3), a key sarin precursor. 49 Baghdad alsoplanned to produce hydrogen fluoride (HF),another essential ingredient in sarin production,by extracting it from phosphate ore with sulfuricacid. By the time of the August 1990 invasion ofKuwait, Iraq was on its way to building anindigenous capability to produce all of the majorprecursors of tabun and sarin, although it ultimatelydid not achieve this objective. 50The Iraqi case suggests that a country withlarge deposits of phosphate ore, a well-developedpetrochemical industry, plentiful energy supplies,and access to the necessary technical know-howcan develop an indigenous capability to produceall the major precursors of mustard and nerveagents. This ‘ ‘back-integration’ strategy wouldenable such a country to circumvent any foreignexport-control regime designed to deny it accessto CW agent precursors. Nevertheless, developinga back-integration capability is a large andcostly undertaking, and may therefore bebeyond the means of all but the richest andmost ambitious states of the developing world.| Containment and Waste TreatmentBecause of the toxicity of CW agents, containmentmeasures may be taken to ensure the safetyof the plant workers and the nearby population.Such measures include air-quality detectors andalarms, special ventilation and air-scrubbing systems,protective suits and masks, and chemicalshowers for rapid decontamination. The safetyand ventilation measures at the Iraq’s Al MuthannaCW production plant included measures comparableto U.S. procedures in the 1960s, when mostof the U.S. chemical weapon stockpile wasproduced. 5lFor this reason, one should not use currentU.S. safety and environmental standards as thenorm when judging the likely proliferationpaths of developing countries. If a ruthlessgovernment is willing to tolerate large numbers ofinjuries or deaths among production workers, CWagents can be manufactured in a very rudimentaryfacility with few, if any, systems in place toprotect worker safety or the environment. In theformer Soviet Union, for example, closed CWagentproduction facilities were only introducedin the 1950s; before then the production processwas entirely open to the atmosphere. Accordingto a Russian scientist, production of blister agentsduring World War II took place under horrifyingconditions:In Chapayevsk we sent many thousands ofpeople “through the mill” during the war.Soldiers who had been deemed unfit worked atthe plant. Production was completely open:mustard gas and lewisite were poured into shellsfrom kettles and scoops! In the space of a fewmonths the ‘‘workers in the rear’ became invalidsand died. New people were brought into48 Ibid., p. 52.49 CmS, op. cit., footnote 18, pp. 22-27.50 I$News ~nolog: August through November 1991, “ Chemical Weapons Convention Bulletin, No. 14, December 1991, p. 8,51 D=, op. cit., footnote II.

32 I Technologies Underlying Weapons of Mass Destructionproduction. Once during the war a train bringingreinforcements was delayed for some reason, andthe plant stopped work. There was simply no onethere to work! In nearby villages and hamletsthere is probably no family which has not had arelative die in chemical production. 52If a proliferant country is concerned aboutprotecting its environment or population (orwishes to cover up telltale evidence of its CWactivities), the treatment and disposal of wastesfrom CW agent production poses a technicalchallenge. The waste stream contains hot acidscontaminated with lethal agents and a largequantity of phosphates. Cleaning out the productionline also requires large quantities of decontaminationfluid, which becomes mixed withchemical agent and must be chemically or thermallydestroyed to dispose of it an environmentallysound manner. In the most modem plants,many spent or unused chemicals (e.g., DMMP,thionyl chloride) are recycled back into theproduction process. With the effective use ofrecycling, about one-half ton to 1 ton of waste isgenerated for each ton of nerve agent produced;without recycling, the ratio of waste to product ismuch higher. 53| Weaponization of CW AgentsThe weaponization of CW agents involvesthree steps:1. the use of chemical additives to stabilize oraugment the effects of a CW agent;2. the design and production of munitions fordispersal of agent; and3. the filling, storage, and transport of munitions.Each of these steps is discussed in detail below.CHEMICAL ADDITIVESThe principal military requirements of a CWagent are that it be sufficiently toxic to producelarge numbers of casualties, and thermally andmechanically stable enough so that it can surviveexplosive dissemination or passage through aspray device. Several chemicals may be added toCW agents to allow long-term storage or toenhance their military effects against personnel:Stabilizers (e.g., amines) prevent the degradationof CW agents exposed to hot temperaturesor stored for long periods by absorbingacids released by chemical decomposition.Although CW agents filled into munitions donot require a long shelf-life if they are usedimmediately in combat, stockpiled munitionsrequire stabilizers to prevent deteriorationover a period of years.Freezing-point depressants lower the freezingpoint of liquid CW agents primarilymustard) to permit use under winter conditions.Thickeners increase the viscosity and persistenceof liquid agents.Carriers increase the airborne concentrationof an agent like sulfur mustard, which is notvery volatile at normal temperatures. DuringWorld War II, Germany did research on thepotential use of silica powder as a potentialcarrier for mustard agents. A large quantityof sulfur mustard can be absorbed onto thepowder and dispersed as a dust cloud.Because it contains a higher concentration ofagent, ‘‘dusty mustard’ produces more seriousand rapid casualties than droplets ofliquid agent. 54‘ 2 “Mirzayanov, Fedorov Detail Russian CW production” op. cit., footnote 34, p. 4.53 fia~ord & Russell, ~c,, Selection ati Demonstration of the A40st Suitable Processor the Production of Methylphosphom”c Dichloride(Aberdeen Proving Ground, MD: U.S. Army Chemical Research Development and Engineering Center, Dec. No. CRDEC-CR-87086, June1987).S4 j. pev Robinson and w Tmpp, ‘‘~uction and Chemistry of Mustard Gas, ” S, J. Lund@ cd., Verzficatz”on of Dual-use ch~”calsunder the Chemical Weapons Convention: The Case of T)u”odiglycol, SIPRI Chemical & Biological Warfare Studies No, 13 (New York OxfordUniversity Press, 1991), p. 8.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation | 33■ Antiagglomerants, such as colloidal silicaprevent caking of powdered agent.Although stabilizers are added routinely to CWagents, thickeners and carriers are more difficultto use. Thickeners, for example, do not readily gointo solution and may take several hours todissolve. Countries that do not require agents withhigh effectiveness or a long shelf-life may simplychoose not to use additives, thereby simplifyingthe production process.FILLING OPERATIONSIn a CW agent production facility, the toxicmaterial may flow directly from the productionreactors to a munitions filling plant, where it isloaded into artillery shells, rockets, bombs, orspray tanks. Alternatively, the agent may bestored in bulk so that military missions can beconsidered when matching agents to munitions,or in the expectation that new delivery systemswill be developed.Because the filling operation is extremelyhazardous, it is typically performed inside asealed building with a controlled atmosphere; thefilling machines themselves are totally enclosedand sealed from the external environment. Theprimary technical challenge is to seal the supertoxicliquid inside the munition without leakageand then to decontaminate the external surfaces.Iraq filled its unitary CW munitions on anenclosed, automated assembly line at the AlMuthanna production complex near Samarra.Such filling and sealing operations typically takeabout 2 to 3 minutes per projectile. 55A proliferant country might also fill CWmunitions manually, although this operation wouldbe labor-intensive and extremely dangerous. (Recallthe quote above describing the manual fillingof shells at a Soviet mustard plant during WorldWar II.) During manual filling, a plant workerwearing a gas mask and protective clothingtransfers the agent through a hose from a storagevessel to the munition, which must then beplugged and sealed without any vapor loss orspillage. In wartime, filled munitions would betransported from stockpiles to positions on thebattlefield from which they wouId be used. Otherpreparatory activities, such as inserting fuses andbursters, would also be required.MUNITIONS DESIGNChemical munitions are designed to convert abulk payload of liquid or powdered agent into anaerosol of microscopic droplets or particles thatcan be readily absorbed by the lungs, or a sprayof relatively large droplets that can be absorbedby the skin. 56 An aerosol consists of dropletsbetween 1 and 7 microns (thousandths of amillimeter) in diameter, which remain suspendedin the air for several hours and are readily inhaleddeep into the lungs. In contrast, a spray capable ofwetting and penetrating the skin consists ofdroplets at least 70 microns in diameter. 57A volatile agent like sarin is disseminated as afine aerosol to create a short-term respiratoryhazard. More persistent agents like sulfur mustardand VX are dispersed either as an aerosol (forrespiratory attack) or as a coarse mist (for skinattack or ground contamination). After dissemination,nonvolatile agents may remain in puddleson the ground for weeks at a time, evaporatingvery slowly. The quantity of agent required toaccomplish a particular military objective dependson the toxicity of the material involved andthe efficiency of dissemination.Many of the design specifications for chemicalmunitions can be found in the open patentliterature, and suitable munitions productionplants exist in many parts of the world. Anaerosol or spray of CW agent may be disseminatedby explosive, thermal, pneumatic, or mechanicalmeans. The simplest device for deliver-SS D&, op. cit., foomote 11.S6 J. H. Ro~~ld, To~mo~’~ Weopom: che~”cal a~Biological (New Yc)*, w: McGraw-Hill, 1964), p. 66.57 ~wwd M. Spires, Che~”ca[ WeaponV: A Continuing Challenge (New York NY: St. m’s ~ss~ 19W~ P. 21.

34 I Technologies Underlying Weapons of Mass Destructioning CW agents is a liquid spray tank mounted onan airplane or helicopter; such systems arecommercially available for the dissemination ofagricultural chemicals. To deliver an aerosol orspray of agent close enough to the ground toproduce casualties, however, an aircraft must flyat low altitude and is thus vulnerable to airdefenses, if they exist.CW agents can also be delivered with a widevariety of munitions. During the Iran-Iraq War,for example, Iraq delivered mustard and tabunwith artillery shells, aerial bombs, missiles, rockets,grenades, and bursting smoke munitions. 58 Abursting-type munition is packed with chemicalagent and a high-explosive burster, a fuse, and adetonator; the use of more explosive produces afreer aerosol but may destroy much of the agentin the process. The fuse may be designed either toexplode on impact with the ground or, using aproximity fuze, at an altitude of about 15 feet toenhance the formation of the aerosol cloud. 59Sarin does not burn, but VX does and is thereforedisseminated nonexplosively from a spray tank orby simple injection into the air stream from anaircraft or glide bomb.Binary munitionsChemical munitions can be either unitary orbinary in design. Unitary munitions are filledwith CW agent at a loading facility (oftencolocated with the production plant) before beingstored and transported, so that only a fuse need beadded before use. Binary munitions, in contrast,contain two separate canisters filled with relativelynontoxic precursor chemicals that mustreact to produce a lethal agent. The two componentsare either mixed together manually immediatelybefore firing or are brought together automaticallywhile the binary bomb or shell is inflight to the target. Contrary to general belief,the chemicals produced in binary weapons arenot novel CW agents but rather well-knownones, such as sarin, soman, and VX. (Fortechnical reasons, tabun cannot be producedin a binary system).The United States developed three binarychemical munitions: a 155mm artillery shell todeliver sarin against enemy troop concentrationson the battlefield; the BIGEYE spray bomb todeliver VX against fixed targets deep behindenemy lines; and a warhead for the MultipleLaunch Rocket System (MLRS) containing amixture of intermediate-volatility agents. 60 Thebinary artillery shell is a liquid/liquid system: oneof the two precursor chemicals is isopropylalcohol (rubbing alcohol), while the other, methylphosphonicdifluoride (DF), is less toxic thantear gas. 6l In contrast, the BIGEYE spray bomb isa solid/liquid system: after the bomb is released,a pyrotechnic gas cartridge mixes particulatesulfur with a liquid precursor code-named QL toform VX. After the reaction has occurred, thebomb glides across the target, dispersing VX in itswake as a spray.62 The development Of advancedbinary munitions entails considerable engineeringchallenges, both to accommodate the twocomponents in a ballistically sound package andto effect the necessary chemical reaction duringthe flight of the shell or bomb.58 Hmey J. ~George, t ‘~’s s-et Arsed, ’ Defense & Foreign A#airs, January/February 1991, p. 7; ~~orge, ‘‘The Grow@lTrend ‘fbward Chemical and Biological Weapons Capability,” D@ense and Foreign Affairs, April 1991, p. 6.59 Buck ~d ~owerree, op. cit., footnote 14, P. 5~507.~ Dan Boyle, “AnEnd to Chemical Weapons: What Are the Chances?” Znternutionul Defense Review, vol. 21, September 1988, p. 1088.Although the 155mm shell and the BIGEYE bomb were produced, the MLRS system was termina ted in the final stages of development.61 ~ ~, DF ~ ~ LDw (le~ dose in 50 percent of a population) of 67,000 mg/min/m3, compared with 63,000 m_3 for CS (t~gas). DF and isopropyl alcohol are loaded into the munition in separate canisters; when the round is fued, the forces of acmleration mpturethe wall between the canisters and allow the two reagents to mix. By the time the shell strikes the earth, the reaction is complete; the fuzedetonates a burster charge, which disseminates a cloud of aerosolized sarin. Dee, op. cit footnote 11.62 D&, op. Cit., foo~ote 1 1.

—— —Chapter 2–Technical Aspects of Chemical Weapon Proliferation | 35Nevertheless, binary CW weapons do notnecessarily require sophisticated munition designs,since the two precursor chemicals can bepremixed manually on the ground immediatelyprior to use. Iraq, for example, developedcrude binary nerve-agent bombs and missilewarheads because its DF precursor was veryimpure, causing the sarin product to decomposerapidly. As a result, the Iraqis planned to mix thebinary precursors at the last possible momentbefore firing. At the Al Muthanna CW productionfacility, Iraqi workers half-filled 250-kilogramaerial bombs and Scud missile warheads with amixture of isopropyl and cyclohexyl alcohols,and stored the DF component separately in plasticjerry cans. The operational plan was that justbefore the bombs and missiles were prepared forlaunch, a soldier wearing a gas mask would opena plug in the bomb casing or warhead and pour inthe contents of four jerry cans of DF; the ensuingreaction would result in a 60-40 mixture of sarinand GF (a more persistent nerve agent). 63Binary weapons offer advantages in terms ofease and safety of production, storage, andtransport, and hence might be attractive to potentialproliferants. Nevertheless, binary weaponscreate operational drawbacks on the battlefield.The two precursors must either be premixed byhand-a dangerous operation----or separate canisterscontaining the two ingredients must beplaced inside each munition immediately beforefiring.Cluster bombsOne way to increase the area coverage of anaerial bomb or missile warhead is by means ofcluster munitions, in which the chemical payloadis broken up into many small bomblets (submunitions)that are released at altitude and scatter overa large “footprint’ on the ground. During WorldWar II, the United States developed chemicalcluster bombs that carried 100 bomblets, eachcontaining 5 kg of mustard, Such weapons wereUnited Nations inspector sampling DF, a nerveagent precursor that had been dumped into a pit inIraq. The Iraqis stored DF separately from theirchemical munitions, intending to add it just before useto form the nerve agents sarin and GF.designed to release the bomblets in a randompattern at an altitude of 1,000 feet; individualparachutes slowed the descent of the bomblets sothey would not bury themselves in the ground.MISSILE DELlVERY SYSTEMSBallistic missile systems such as the SovietdesignedScud-B (with a range of 300 km) andFROG-7 (with a range of 67 km) can deliverwarheads bulk-filled with chemical agent. Iraqdeveloped bulk chemical warheads for its Al-Hussein modified Scud missiles (with an extendedrange of 500 to 600 km), although there is63 Terry J. Gander, “Iraq--The Chemical Arsenal,” June’s Intelligence Review, vol. 4, No. 9, September 1992, p. 414.

36 | Technologies Underlying Weapons of Mass DestructionIraqi worker preparing to open up for inspection achemical warhead developed for Iraq’s modified Scudmissile.no evidence that they were actually tested. 64United Nations inspectors in Iraq were shown 30CW missile warheads, of which 16 had unitarysarin warheads. The other 14 were of the “binary”type and were partially filled with amixture of alcohols pending the addition of DFstored in jerry cans nearby.During the 1950s, the United States alsodeveloped CW cluster warheads for a series ofrockets and missiles, including the Honest John,Sergeant, Improved Honest John, and the developmentalLANCE warhead. A cluster warhead,however, cannot cover an area large enough toensure that a missile as inaccurate as a Scud willdeliver chemical agent to a particular target.Moreover, the area covered by a cluster warheadis somewhat unpredictable, since it depends to alarge extent on the terrain and weather in thetarget zone.Cruise missiles and remotely piloted vehicles(RPVs) are also potential CW delivery systems.During World War II, the Germans consideredfilling the warhead of the V-1 flying bomb withphosgene gas instead of the normal 800kilogramsof high explosive. They decided against thisproposal, however, after calculating that highexplosives would actually produce more casualtiesthan gas. 65 Nevertheless, a cruise missile orlong-range RPV fitted with a 500 kg spray tankwould be a cheap and effective delivery systemthat could lay down a linear spray cloud of CWagent.In sum, systems suitable for delivering CWagents are widely available, and even the developmentand production of crude (manually mixed)binary weapons does not require a sophisticatedindustrial base. These observations suggest thatthe weaponization step does not pose atechnical bottleneck to the acquisition ofcapability.majora CWINDICATORS OF CW PROLIFERATIONACTIVITIESVerification of the international ban on chemicalweapons will require the capability to detectmilitarily significant production of CW agents ina timely manner. Even a small production facilitycould manufacture militarily significant quantitiesof CW agent if it is operated for several years.Over a decade, a pilot-scale plant producing 10tons of agent per year would accumulate 100tons-a militarily significant quantity under certaincontingencies. 66 Such long-term accumulationwould, however, require distilling the agentto ensure a long shelf-life, thereby increasingcomplexity and cost; otherwise the total quantityof agent would be reduced by deterioration overthe lo-year period. Increasing the number or scaleof the production plants would reduce the lengthof time needed to accumulate a militarily significantstockpile.64 Dw~ McHug& ‘‘~w COnfeRII@,’ Trust and Venfi, No. 35, hnuary 1992, p. 2.65 Harris and P~ op. cit., footnote 25, p. 59.66 ~uel L, sm~he~ et ~., A~ly~i~ of sig~~~resAssociated with No~co@iunce sce~~os, Repofi No. DNA-TR-92-74 (&kgton, VA:System PhMx@ Corp., January 19’93), p. 7.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation 137Monitoring measures designed to detect illicitCW production may be cooperative, within theframework of the Chemical Weapons Convention(CWC), or noncooperative, based on intelligenceagents, remote sensing, and covertly placedmonitoring devices that are not part of a negotiatedregime. The cooperative monitoring regimeestablished by the CWC requires participatingcountries to submit declarations, which will thenbe checked through ‘‘routine’ onsite inspections;discrepancies may suggest illicit activities. Todeter clandestine CW agent production, the treatyalso provides for “challenge” inspections atgovernment or private facilities, declared orundeclared. The advantage of the cooperativeregime is that it permits direct access to productionfacilities, albeit in a tightly circumscribedmanner. In contrast, unilateral intelligencegatheringefforts have the advantage that they arenot constrained by agreed restrictions on datacollection. The two approaches are not mutuallyexclusive and can be employed in a complementarymanner.Several potential indicators, or “signatures,”of CW development, production, and weaponizationare discussed below. Although each signaturetaken in isolation is probably inadequate toprove the case, a “package” of signatures fromvarious sources may be highly suggestive of aCW capability. Evaluating the effectiveness ofthe verification regime for the Chemical WeaponsConvention must take into the account the specificityand sensitivity of these various signaturesand how much confidence one might have inthem. The following analysis does not attempt afull assessment of the CWC verification regime(e.g., detailed procedures for inspections) butfocuses more narrowly on the utility of thevarious signatures that might be monitored.A separate but related issue is the quality of theevidence needed to ‘ ‘prove’ to the internationalcommunity that a country has violated its treatyobligations, and the consequences of detecting aviolation. This issue of the standard of proof hasbeen a long-standing problem of verification.Although there may be sufficient evidence toconvince some countries that a violation hasoccurred-particularly if they are suspicious tobegin with-the case may not be unassailable inthe face of the accused party’s plausible denials.At the same time, the accusing party may not wishto release all of its supporting evidence to a largeraudience because of the risk of compromisingsensitive sources and methods of intelligence.The standard-of-proof problem has no simplesolution and should be kept in mind during thefollowing discussions of ‘signatures” of chemicalweapon acquisition.| Research and Development SignaturesThe frost stage in the acquisition of a CWcapability is laboratory research and developmentof offensive agents, although this step is notnecessary if standard agents and known productionprocesses are to be employed. The followingstep is pilot-scale production to work out problemsin the manufacturing process. Because of thesmall scale of these operations, they can be verydifficult to detect.SCIENTIFIC PUBLICATIONSOne way of tracking a country’s research anddevelopment activities relevant to CW is to readits contributions to the chemical literature. Thefact that leading academic chemists suddenly stoppublishing may bean indicator of military censorshipor the diversion of civil scientists intodefense work. Publication tracking can alsoproduce red herrings, however, since changes inscientific productivity may result from manyfactors. During World War II, for example, theGermans read great significance into the fact thatreferences to new pesticides suddenly disappearedfrom U.S. scientific journals. Germanintelligence analysts deduced correctly that militarycensorship was responsible for the cut-off,but they wrongly assumed that the United Stateshad independently discovered nerve agents. TheGermans’ faulty intelligence assessment led themto fear U.S. retaliation in kind if they initiated the

38 | Technologies Underlaying Weapons of Mass Destructionuse of nerve agents, and was one of several factorsthat deterred them fiorn resorting to chemicalwarfare. 67While publication tracking might provide cluesto technologically advanced CW developments, itwould be much less useful in the case of adeveloping country like Iraq that is simplyattempting to produce standard agents with knownproduction processes. Such a country wouldemploy mainly industrial. chemists and chemicalengineers, who publish very little in the openliterature. For this reason, publication trackingis likely to be of only secondary value inmonitoring CW proliferation.HUMAN INTELLIGENCE (AGENTS ORDEFECTORS)Human agents, defectors, or even leaks to thepress in more open societies can be of value inrevealing the existence of secret chemicalwarfareR&D activities. In October 1992, forexample, Vil Mirzayanov, a Russian militarychemist, gave interviews to the press in which hestated that scientists at the State Union ScientificResearch Institute of Organic Chemistry andTechnology in Moscow had developed a newbinary nerve agent that, in terms of its combatcharacteristics, was “five to eight times superior’to the most toxic of the VX-type agents nowin existence. Mirzayanov also alleged that a batchof between five and 10 metric tons of the newagent had been produced. 68 He was subsequentlyarrested by the Russian Security Ministry (thesuccessor to the KGB) and charged with revealingstate secrets. 69 Because human-intelligence reports--particularly those based on hearsay or indirectevidence—may be misleading, however, theytypically need to be confirmed with other, moreobjective forms of evidence before being used tosupport final conclusions.| External Production SignaturesSince so much of CW agent production involvesdual-use technologies, it is necessary todistinguish clearly between illicit and legitimateproduction. Unfortunately, there are few, ifany, specific, unambiguous external signaturesof CW production. A number of potentialindicators are discussed below.PATTERNS OF MATERIAL AND EQUIPMENTIMPORTSDeveloping countries seeking to acquire a CWcapability are nearly always dependent on outsideassistance, at least in the initial stages. During the1980s, numerous companies from Western Europeand Japan sold chemical plants to proliferantcountries, which then converted them into CWproduction facilities. Different suppliers providedthe laboratories and production plants, sold chemicalprecursors, and furnished maintenance equipment.Iraq, for example, was able to purchase 7turnkey chemical plants and to order thousands ofcatalogue parts on the international market, alongwith all the necessary precursor chemicals for theproduction of CW agents. Similarly, the LibyanCW plant at Rabta was designed by the WestGerman firm Imhausen-Chemie and built bycompanies from ‘‘nearly a dozen nations, Eastand West, ’ according to Robert M. Gates, thendeputy director of the National Security Council.70Because of the initial reliance of proliferants onoutside assistance, suspicious exports and importsof production equipment and chemical157 Harris and Paxmanj op. cit., footnote 25, p. 64. For a discussion of other factors that convinced the Germans not to use chemical weapons,see Frederick J. Brow Chemical Wa@are: A Study in Restraints (Princeto~ NJ: Princeton University Press, 1%8); and John Ellis vanCourtland MOOQ “Chemical Weapons and Deterrence: The World War II Experience,” International Secun”ty, vol. 8, No. 4, spring 1984, pp.3-35.68 ~~~zaymov, Fedorov Dew Russian CW pmductio~” Op. Cit., fOOrnOte 34, P. 2.69 Serge Schrnernann, “K,G.B,’s Successor Charges Scientist,” New York Times, Nov. 1, 1992, p. 4.70 William Thohy, ‘ { U.S. Pressing Allies on Libya Chemical Plan4° Los Angeles Times, Jan. 3, 1989, p. 10.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation 139precursors may indicate the acquisition of a CWproduction capability. For this reason, monitoringexports of materials considered critical for CWproduction, such as glass-lined pipes and corrosionresistantalloys, could prove useful. 71 Since muchof this equipment is dual-use, however, itsacquisition is not necessarily proof of an intent toproduce CW agents. Moreover, tracking suchtransactions is difficult because proliferants likeIraq and Libya take care to set up elaboratenetworks of ‘front’ companies, paper subsidiaries,and middlemen to hide their purchases.Precursors of CW agents are also difficult totrack. Unlike weapon-grade fissionable materials(e.g., highly enriched uranium and plutonium),which are produced in relatively small quantitiesand have quite restricted civil uses, most CWprecursors have legitimate commercial applicationsand are traded internationally in volumesthat make precise accounting impossible. Auseful case study is that of thiodiglycol, theimmediate precursor of sulfur mustard. Since alimited number of companies and countries manufacturethis chemical, it was initially believedthat calculating the agreement between its productionand consumption, or material balance,might provide a way to detect diversions fromlegitimate commercial uses to illicit mustardproduction.In 1989-91, a working group of the internationa1scientists’ organization Pugwash studiedthe feasibility of such a monitoring effort. Theyfound that since thiodiglycol could be producedsecretly or diverted from legitimate uses withrelative ease, an effective control regime wouldrequire: 1) continuous monitoring of all chemicalplants capable of producing it, and 2) establishinga materials balance between starting materialsand products at all stages of its life-cycle. ThePugwash team concluded that such a monitoringsystem would be extremely difficult and costly toimplement. Moreover, standard inaccuracies indata-gathering on feedstock chemicals couldmask the diversion of significant quantities ofthiodiglycol for the production of mustard agent,rendering mass-balance calculations of questionableutility .72Tracking phosphorus-based compounds usedto make nerve agents is even more difficult.Billions of pounds of these chemicals are boughtand sold for commercial purposes, so that militarilysignificant quantities would be lost in the‘‘noise’ of international trade. Because the productionof many basic commodity chemicals isshifting from the industrialized countries to thedeveloping world, some precursor chemicals areproduced at multiple locations in several countries,greatly complicating the difficulty of materialaccounting. Moreover, given the long intervalbetween order and delivery, it is difficult toaccount for materials in transit.At the level of an individual plant, calculatingthe material balance between the feedstocksentering a plant and the products coming out isonly possible to an accuracy of 2 to 3 percent—amargin of error too large to prevent a militarilysignificant diversion of precursors to CW agentproduction. Calculating a precise material balancewould also require extensive access to acompany’s production records and might thereforejeopardize legitimate trade secrets. As aresult, materials-balance calculations cannotprovide a reliable indicator that precursorchemicals are being diverted to CW agentproduction.Some analysts have suggested that the ratios ofstarting materials and catalysts needed for CWagent production might provide reliable signaturesbecause they are distinctive from those usedin commercial production. For example, a plantproducing 10 tons of sarin per day would needlarge quantities of precursors and catalysts in71 Robert Gillette, “Verification of Gas Plant a Murky Task” ,QM Angeles Times, Jan. 5, 1989, p. 5.72 Martin M. Kaplan et al., ‘‘Sumrnary and Conclusions, ’ Verification of Dual-Use Chem”cals Under the Chemical Weapons Convention:The Case of ?’hiodigZycol, S. J. Lundti ed. (Oxford, England: SIPRI/Oxford University Press, 1991), pp. 124-136.

40 | Technologies Underlying Weapons of Mass Destructionspecific proportions. Nevertheless, many complexfactors influence the quantities of precursorchemicals consumed by a chemical plant, includingthe stoichiometry of the reactions used foragent production, the number of production steps,and the yield of each step. 73 Some reactants mightbe used in excess to boost yield or to increasereaction rates, and feedstocks could be deliberatelystockpiled to distort the calculated ratios.For these reasons, ratios of starting materialsare unlikely to provide a reliable indicator ofCW agent production.The presence of key additives (e.g., stabilizers,thickeners, or freezing-point depressants) in associationwith precursor chemicals may be indicativeof CW agent production. Because the use ofadditives is generally optional, however, theirabsence would not necessarily rule out illicit CWagent production.ECONOMIC DISLOCATIONSThe clandestine diversion of a large commercialchemical plant (and associated precursormaterials) to CW production might have a noticeableimpact on the local economy in a small,underdeveloped country with relatively littleeconomic activity. For example, temporarilyceasing civilian production might create observableshortages of consumer goods normally producedby the plant, such as pesticides or drugs.Whether such economic dislocations would beobservable, however, depends on the extent towhich the chemical plant was integrated into thelocal economy. In more industrialized countriessuch as India, South Korea, and Taiwan, suchrelatively small economic effects would be obscuredby the ‘‘noise” of fluctuating outputwithin the overall economy. Moreover, in somedeveloping countries, chemical production isentirely for export, so that one would have tomonitor foreign sales rather than domestic markets.A proliferant country might also stockpile aportion of its output for several months or yearsand use it to make up for shortfalls in normalproduction. As a result, economic dislocationsare unlikely to be a reliable signature.VISUAL SIGNATURESUnlike nuclear weapon facilities, which aresingle-use, limited in number, and easy to identify,civilian chemical plants are two orders ofmagnitude more numerous, have multiple uses,and are configured in different ways dependingon the chemical process. Moreover, there are nounique features or external markings that woulddistinguish a facility capable of CW agent productionfrom an ordinary chemical plant. 74 Aclandestine military production facility might behidden underground or inside a mountain, orembedded within a legitimate chemical complex,making it essentially invisible from the air.Chemical munitions are small, impossible todistinguish visually from high-explosive shells,and easy to conceal, as are bulk chemical agents.Indeed, 100 tons of nerve agent—a militarilysignificant quantity in many conflict scenarios—would fit into a dozen trailer-trucks. 75 A proliferantcountry might therefore hide chemical weaponsor bulk agent on railcars, in undergroundbunkers, or in inconspicuous buildings.Despite these limitations, however, a patternof anomalous visual indicators at a chemicalfacility might arouse suspicions that could beverified by other means. Indicators of CWproduction that might be visible in overheadimagery obtained by reconnaissance aircraft orsatellites include:73 ~k F. M~le~ Kenne~ E. Apg and William D. StanbrO, Criten”a for Monitoring a Chemical Arms fiea~: Implications for theVerification Regime (Los Alamos, NM: IXM Alamos National Laboratory, Center for National Security Studies, Report No. 13, Deeemba1991), p. 8.74 Brief@g by Manuel L. Sanches, System PI arming Corp., Oet, 23, 1992.75 NWeen C. Bailey, “Problems With a Chemical Weapon Ba” Orbis, vol. 36, No. 2, spring 1992, p. 244.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation | 41the construction of a large chemical plantthat has not been reported in the chemicaltrade press; 76siting of the plant in an extremely remote andisolated location;a high level of security surrounding the plant,such as multiple or electrified fences, airdefensebatteries, and guard units;an extremely dispersed layout, with largedistances between buildings to complicateattacks from the air;the proximity of the chemical plant to ametal-machining factory capable of fabricatingmunitions;the presence of tanker trucks associated withthe transport of hazardous chemicals;a lack of steel drums or other packagingmaterials normally associated with the productionof commercial chemicals;traffic movement at night or under guard;the death of vegetation, livestock, birds, orwild animals in the vicinity of a plant;a flurry of activity at a chemical facilitysuggestive of a major accident, yet nocoverage of the event in the local media.Box 2-A provides an example, taken from pressaccounts, of how visual signatures contributed tothe identification of a CW production facility inLibya. The utility of these signatures depends, ofcourse, on the individual proliferant’s approach.Although the visual indicators cited above wouldhave worked well for Iraq, they would have beenunsuccessful in the case of a proliferant thatembedded its CW production facilities withinlarge commercial chemical complexes.In addition to visual signatures, infrared reflectionsor emissions detected by specialized overheadsensors might, in principle, provide indicationsof CW production activity .77 For example,multispectral cameras might detect stressed ordying foliage around a production plant resultingfrom emissions of toxic chemicals. A thermalinfraredcamera might also assist in monitoring afacility’s operational status by revealing theintensity of heat emitted by various parts of theproduction line and smokestacks. Cool and hotbuildings, pipelines, and tanks could be readilyidentified by infrared imaging, indicating whichparts of the facility were active at any giventime-although such evidence could be misleading.78 Synthetic-aperture radar (SAR) imagery,which tends to highlight reflective surfaces,might also reveal details not evident in an opticalphotograph such as feed pipes, power lines, andvehicles parked around a facility . 79 SAR can alsogenerate images of near-photographic quality atnight and in bad weather.Nevertheless, overhead reconnaissance has itslimitations. In addition to the difficulty of distinguishinga CW production facility from anordinary chemical plant in photographs, overheadimagery may be susceptible to deliberate effortsat camouflage, concealment, and deception (CC&D).The Libyans, for example, reportedly engaged inan effective deception campaign that initiallyconvinced Western intelligence agencies that theRabta CW production plant had been destroyed76 ~ ~ma~ he ~~e pr~s r~om on the construction Of M =JOr lcgi~te ch~c~ p~ts.77 For ~ddition~ ~omtion on ~efi~ce ~d remo~ ~~~g, see Us. co~ess, ~~ of ~hnology Assessmen~ Cooperative findSunei/lance in InfernafionalAgreemenrs, OTA-ISC-480 (Washingtortj DC: U.S. Government Printing OfIlce, July 1991) and U.S. Congress,OfIice of Twhnology Assessment The Future of Remote Sen.n”ng From Space: Civilian Satellite Systems and Applications, OTA-ISC-558(lVashingto% DC: U.S. Government Printing Office, July 1993).75 by Sfithson ~d ~ctiel wepo~ Strengthening the Chem”cal Weapons Convention Through Aen”al Inspections, OCC~iOnd papaNo. 4 (Washington, DC: Henry L. Stimson Center, April 1991), p. 15.79 SPthetic-a-e mdm (Sri) ~mtes a dewed terr~ -p by cqb the refl~tion Of timed microwave p~WX emitted by a IIIOviXlgtransmitter, whose motion creates a synthetic antenna with an apparent diameter much greater than that of the actual transmi tting antenna. Thislarge effective antenna size allows much greater resolution than a stationary radar could achieve, permitting the creation of photograph-likeimages.

42 | Technologies Underlying Weapons of Mass DestructionBox 2-A-How Libya’s Secret CW Plant Was DetectedPress accounts provide an interesting illustration of how patient detective work by the U.S. intelligencecommunity, compiling data from a wide variety of sources, provided strong circumstantial evidence that Libya wasbuilding a clandestine CW facility long before the plant started production. 1 (In summarizing these stories here,OTA is neither confirming nor challenging their accuracy.) The Rabta case therefore provides some useful lessonsin the detection of covert CW proliferation by intelligence means.In the early 1930s, reconnaissance-satellite photos of Libya revealed that a major construction project wasunder way in a hilly region about 35 miles southwest of the Libyan capital of Tripoli. Western intelligence reportsalso indicated that Ihsan Barbouti, an Iraqi-born businessman whose Frankfurt-based engineering firm had beenlinked to the construction of a CW plant in Iraq, was using front companies to ship chemical equipment, supplies,construction plans, and personnel to Libya. Barbouti’s operation involved some 30 German companies, severalAustrian engineers, and Swiss banks. 2The prime contractor was lmhausen-Chemie, a West German chemical firm that became involved with theLibyan project in 1985, at a time when it was in financial difficulties. Most of the equipment and supplies leftEuropean ports under false export documents, and in order to circumvent existing export controls, Barbouti useda complex commercial network involving front companies that transferred goods through ports in the Far East. 3Construction at Rabta was carried out under tight security conditions by 1,300 low-wage laborers imported fromThailand. 4Meanwhile, satellites and high-altitude reconnaissance aircraft followed the progress of construction at theRabta site. By 1938, the imagery suggested that the facility, which sprawled over several acres, was nearingcompletion. Libyan government officials adamantly insisted that the Rabta facility was a pharmaceutical plant,designated Pharma-150. Yet the factory was unusually large by the standards of the pharmaceutical industry andwas ringed by high fences and 40-foot sand revetments-seemingly excessive security for an ordinary chemicalplant. 5 Since the production facility was completely enclosed inside a warehouse-like structure, overheadphotography revealed nothing about the process equipment inside, but the plant’s oversized air-filtration systemsuggested that it was intended for the production of toxic chemicals.Once the overhead imagery had aroused suspicions, Western countries sought to develop new sources ofinformation among the foreign technicians and construction workers from more than a dozen European, Asian,and Middle East countries employed at the Rabta facility. These sources described plant equipment layout, andsupplies, providing additional dues that the site might be intended for CW production. Intelligence analystsconcluded that the complex comprised a large chemical agent production plant, a chemical arms storage building,and a metalworking plant built by Japan Steel Works. 6 The latter facility contained Japanese-made machine tools,officially intended for the production of irrigation pumps but also suitable for the production of artillery shells andgas cannisters. 7 Delivery of special steels used in bomb casings suggested to U.S. and British intelligence that1 %e nOnMS C. Wiegele, 7he Clandestine Bukfing of Ubya’s Chemkal Wapons Factory: A fiudy ininternatiom?i Co/iusion (Carbondale, IL: Southern Illinois University Press, 1992).2 wiiiiamC. Rempei and Robin Wrtgh~ “Libya Piant Found by Vfgiiance, Luck” 77?e Los An.geles ~m% Jan.22, 1989, pp. 1,21.3 ~mthy AW@i, “seg~ng smoking Guns,” 77?e Chdstian -rice hfOt?ikM Jan. 6 1*93 P. 104 WIiIi~ R. i)oerner, “On Seoond Thought” 77nw, vol. 133, No. 4, Jan. 23, 1969, p. al.5 Biii Gerti, %ateliltesspt Poison-Bomb Piant In Uby%” 14&shington 77meq Mar. 5,1991, P. A3.6 Biii Gertz, ‘12nd Chemicai Arms Plant Spied in UbWL” 77?0 Wfk?M@On Thn&% June 18, Iwo, p. A6.7 RotNrt Gilette, ‘ k Verification of Gas Plant A Murky Task” Los Angeies 77~s JWI. 5, 1989, P. 11.

————Chapter 2–Technical Aspects of Chemical Weapon Proliferation \ 43Libya was actually manufacturing chemical munitions?The West German government obtained construction blueprints of the Rabta plant from the engineering firmSaltzgitter. These plans revealed some anomalous features suggestive of CW agent production. According to aGerman government report,The joint planning of chemical plants and the metal processing plant as well as security facilities notusually found in a pharmaceutical facility (airtight windows and doors, gas-tight walls between theproduction and the control unit, burn-off unit, corrosion-proof Iining on pipes, and escape routes) makeit possible to draw the conclusion that ‘Pharma 150’ is a chemical weapon Plant 9It was not until August 1988, however, that the CIA obtained more solid evidence that the Rabta plant wasengaged in CW agent production. Following a partial test run of the production process, an accidental spill occurredas highly toxic wastes were being transferred for diaposal outside the plant. The resulting aloud of fumes killeda pack of wild desert dogs in the vicinity of the plant. Their bodies, detected by satellite, indicated that the plantwas producing chemicals of warfare toxicity. l0The “smoking gun,” however, reportedly came from communications intercepts. During the accident,panicked Libyan officials called Imhausen-Chemie-the West German firm that had designed the plant-foremergency advice. Since the Libyans placed the call over international phone lines, U.S. intelligence was able tointercept the conversation. 11 According to an account in Time magazine, “in a frantic effort to get advice oncleaning up and repairing the plant, Libyan officials spoke at length with lmhausen-Chemie personnel. Thoseconversations left no doubt that employees of the West German firm were just as aware as the Libyans that theplant was being used to produce toxic gas.” 12On September 14,1988, the State Department went public with the fallowing statement: ‘The U.S. now believesLibya has established a CW production capability and is on the verge of full-scale production of these weapons.”CIA director William Webster provided further details in a speech on October 25, 1988 claiming that the Libyanplant was the largest chemical weapon facility the agency had detected anywhere in the developing world. 13 InAugust 1990, the intelligence community deduced that large-scale production of chemical agents at Rabta hadbegun after a photoreconnaissance satellite observed specialized trucks designed to transport CW agents pickingup barrels of suspected agent at the plant. 14 In 1992, an intelligence official stated publicly that the Rabta facilityhad produced and stockpiled more than 100 metric tons of the nerve gas sarin and other CW agents. 15Nevertheless, the public case against Rabta-as reported in the news media-is circumstantial and willremain so until Libya signs and ratifies the Chemical Weapons Convention and permits intrusive inspections ofthe facility. According to a skeptical assessment, “Neither the charges that Libya is attempting to develop chemicalweapons nor the allegations that Libyan forces have used them can be independently substantiated from the public8 J-S Adams, Engines of War: Merchants of Death and the New Arms Ra= (New York Ny: AtiantlcMonthly Press, 1990), p. 243.9 ‘lRe~rt Submitted by the Government of the Federal Republic of G8rmany to the German Bundestag onFeb. 15,1989, Concerning the Possible Involvement of Germans in the Establishment of aChemical Weapon Fadlityin Libya,” reprinted in U.S. Senate, Committee on Foreign Relations, C/?emka/andBio/o@@/ 14&apons: The U@ntNeedforRenwdies, 101st Congress, First Session, Jan. 24, Mar. 1, and May9, 1989 (Washington, DC: GovernmentPrinting Office, 1989), p, 81.10 Rempel and Wright, op. dt., footnote 2, p. 21.~ 1 Ibid, pp. 1, 21.12 Downer, op. dt., footnote 4, p. 31.13 Da~d B. Ottaway, “Behind the New Battte With Libya” The Washington post, Jan. 8, 1989, p. w.14 Gertz, op. cit., footnote 6, p. Al.15 Gordon c. oehler, “Address to the Annual Soref Symwsium of the Washington Institute fOr Near ~Policy,” Apr. 27, 1992, p. 4.

44 | Technologies Underlying Weapons of Mass DestructionBox 2-A-How Libya’s Secret CW Plant Was Detected-(Contfnued)record, but there is sufficient circumstantial evidence to make Libya a strong suspect as a chemical weaponsproliferator:’ 16Moreover, although the detection and monitoring of the Rabta site was an intelligenoe success-story, itremains to some extent a special ease. Because Libya is a desert nation that relies heavily on foreign expertiseand labor, the presence of foreigners provided valuable sources of information. Densely populated andindustrialized countries suspected of having covert CW programs are harder to monitor because they can concealthem in a large and diverse array of chemical plants involved in production of pharmaceuticals, pesticides, andfertilizers. 17 Finally, even in the Rabta case, the inherent unreliabilityof circumstantial evidence underscores theimportance of rigorous onsite inspection in verifying the Chemical Weapons Convention.16 Gordon M. Buck ami Charles C. flowerree, /nfernationa/Handookon Ch@/?Wd 14@@ons %lifemtfon(New Yorlq NY: Greenwood Press, 1991), p. 267.17 Rernpel and Wright, op. dt., footnote 2, p. 21.by fire on March 13, 1990. 80 When the Frenchcommercial Earth-resources satellite SPOT-1 photographedthe Rabta facility on March 18, however,it looked fully intact. 81 According to pressreports, only after several days did the U.S.intelligence community realize that the Libyanshad created the illusion of a major fire at the plantby painting scorch marks on the roofs of buildings,burning several truckloads of old tires toproduce black smoke, and. rushing ambulances tothe area to make it appear that the plant hadsuffered severe damage. 82In sum, external visual signatures, such asthose that might be observed through overheadphotography, can provide clues of CWproduction activities but. are rarely conclusiveand must be supplemented with evidence fromonsite inspections. While it is possible to concludefrom indirect or ambiguous signatures thatsomething suspicious is going on, making aconvincing case that a country has broken itssolemn treaty commitments requires a higherstandard of evidence.| Internal Production SignaturesUnder the CWC verification regime, externalsignatures obtained noncooperatively throughoverhead photography and remote-sensing willbe supplemented with internal signatures obtainedby authorized onsite inspections. Examplesof some internal signatures are discussedbelow.PRODUCTION PROCESS EQUIPMENTAs discussed above, the synthesis of nerveagents requires a few reactions that are rare in theproduction of pesticides: the cyanation reactionfor the synthesis of tabun; the alkylation reactionfor the synthesis of sarin, soman, and VX; and thefluorination reaction for the synthesis of sarin andsoman. 83 Indeed, since alkylation is not requiredfor the production of most organophosphoruspesticides, civil plants employ feedstocks con-So M,ic~e] R. Gordo~ “U.S. Says Fire at Libya Arms Plant May Be a HoaL” The New York Times, w. 31, 1990, p. 3.$1 “S~l Fire, Much Sxnok,” The Econom”st, vol. 314, No. 648, MM. 31, 1990, p. 42.sz Bifl ~~, “satellites Spot Poison-Bomb Plant in Liby%” The Washington ~“~S, ~. 5, 1991, p. 3.$3 Bm~ op. cit., footnote 33, p. 155.84 me Phosphom us~ in most pesticides is Pentavalent rather* triv~ent.

Chapter 2—Technical Aspects of Chemical Weapon Proliferation 145taining a different chemical form of phosphorusthan is used to make nerve agents. 84Unfortunately, there is no “signature equipmentfor the manufacture of CW agents. SinceCW agents can be and have been produced by avariety of standard organic-chemical processes, itis almost impossible to identify an individualpiece of equipment that has been specificallydesigned or modified for this purpose. This factmakes it extremely difficult for all but the mosttrained eye to spot a CW production facility. Thenecessary equipment would tend to be standardrather than unique, consisting of chemical reactionvessels and “back-end’ processing equipment.Distillation columns, for example, are notnecessarily a good indicator of illicit activitybecause they are also found in many legitimatechemical plants. They might also be omitted froma CW production facility if the proliferant doesnot require pure agent with a long shelf-life.Still, a combination of subtle changes inplant design and layout might be indicative ofillicit production, particularly if an analysis ofthe design suggests that it does not makeengineering and economic sense for its declaredcommercial purpose. For example, unusualprocess steps such as alkylation might standout if they are inconsistent with the plant’s pastorpresent mix of commercial products or are notbeing carried out on an appropriate scale. A plantdesigned to work with highly toxic materialsmight also have specialized pumps and valveswith double seals and other safety measures. Insuch cases, a more intrusive inspection would bewarranted to verify that the suspect facility is notengaged in CW production activities.Another feature of a nerve-agent productionplant that might help distinguish it from anordinary pesticide plant is the means of heatingand cooling the reaction vessels. Since chemicalprocesses for nerve agents produce highly unstableintermediates that react explosively withwater, steam-heating and water-cooling must bereplaced with special heat-exchange fluids andheating oils that require the use of cooling towersrather than steam vents. A nerve-agent productionplant would therefore lack the steam clouds thatare a common feature of chemical plants. 85 Evenso, this signature would not necessarily be uniqueto nerve-agent production, since many legitimatechemical plants use organic solvents or mineraloils as heating and cooling media rather thansteam or water. Moreover, a shrewd proliferantseeking to avoid detection might deliberatelyinstall misleading steam-cloud generators!In general, analysis of plant design and layoutis most useful in the case of turnkey plantsdeveloped and exported by foreign companies,which tend to use distinctive design formats andtemplates. Indigenously designed chemical plantsmay have unique layouts that make it moredifficult to draw inferences about their functions.CORROSION-RESISTANT MATERIALSSince the reactions needed to produce mustardand nerve agents are highly corrosive, along-termCW production facility might use corrosionresistantpipes, valves, and reaction vessels madeof special alloys with a high nickel content, suchas Hastelloy. Unfortunately, there is currently nopractical method to identify corrosion-resistantmaterials without taking physical samples orlooking inside, particularly if a reactor or pipe ispainted or wrapped in insulating material. 86Moreover, the use of corrosion-resistant reactorsand pipes is increasingly common in the civilianchemical industry. Since commercial manufacturersmay wish to avoid replacing vessels andpipes on a regular basis, some advanced commercialplants build in an extra level of protection byinstalling Hastelloy or glass-lined reaction vesselsto protect equipment and maintain product85 Stoctiolm hte~tion~ peace Resewch wti~te, The Problem of Chem”calandBiological Warfare, Vol. VI: TechnicalAspects of ~rlyWarning and Verification (Stockholm: Almqvist & Wiksell, 1975), p. 293.86 Smches et al., op. Cit., fOO~Ote 66, P. 63”

46 I Technologies Underlying Weapons of Mass Destructionpurity. A proliferant country might also be able toacquire used corrosion-resistant equipment thatstill has a few years of life in it after theguaranteed 5 to 10 years have expired. 87Conversely, a proliferant engaged in the covertproduction of CW agents might choose deliberatelynot to use corrosion-resistant materials forthe following reasons:such materials might not be available becauseof export controls;the use of such materials might reveal theintent to produce CW agents; orthe near-term capital cost to extend the life ofthe equipment would not be justified, particularlyif a country planned to produce only alimited stockpile of chemical weapons.Although a stainless-steel reactor will be severelycorroded by HF gas, it can still function forabout a year. A proliferant might therefore bewilling to live with the inconvenience of replacingequipment at shorter intervals and use ordinaryconstruction materials in an attempt toconceal its activities. For this reason, the presencein a chemical plant of corrosion-resistantmaterial does not necessarily indicate that C Wagents are being produced, and its absencefrom a suspect facility may merely reflect thefrequent replacement of standard equipmentor a lack of plans for long-term agent production.SAFETY AND POLLUTION-CONTROL EQUIPMENTThe toxicity of nerve agents is roughly 1,000times greater than that of most organophosphoruspesticides. Nevertheless, only the last step inagent production poses a serious toxic hazard; inthe case of both G and V agents, this is a verysmall part of the process. To prevent the releaseof deadly fumes into the environment, the finalprocess step in a CW production plant wouldprobably be carried out in a tightly sealedenclosure, operated at a negative pressure so thatany leaks would result in air being drawn in ratherthan toxic gases escaping. Reaction vessels involvedin this step might also be operated byremote control, requiring special piping andcomputer systems, and pumps might be equippedwith double or triple seals to guard againstleaks. 88A CW production plant might also haveventilation and emission-control systems thatdiffer from those of a legitimate pesticide orpharmaceutical plant. In pesticide plants, fresh airoften circulates continually through the plant andvents directly into the atmosphere. Althoughincreasingly stringent environmental regulationsare strengthening emission controls in developedcountries, pesticide plants in developing countriesare likely to be open to the environment. 89Similarly, pharmaceutical plants generally shieldproducts from contamination by maintaining theproduction area at a higher air pressure than theoutside environment, so that all contaminantsflow away from the production process. Incontrast, in a CW agent plant the final productionsteps would probably be maintained at a lowerpressure than the outside air so that the lethalvapors do not leak into the surrounding environment.The hazards associated with production ofnerve agents might also require the use of largeactivated-carbon filtration systems and scrubbersto remove all supertoxic chemicals from theexhaust air. The German firm of Noske-Haeser,for example, installed an expensive air-cleaningplant for the Iraqi chemical laboratory at SalmanPak Intelligence analysts concluded that thedimensions of the air-cleaning system were toolarge if the 10 laboratories were simply engagedin commercial research and development, partic-87 @rdon BUC~ W corporation ~rSOId CO-uniCdO~ 1992.88 Bwc~ op. cit., footnote 13, p. 129.69 peter M. ~pf, “Appen& A: The Chemis@y of Organophosphate Nerve Agen@, ” Benoit Morel and Kyle Olso~ eds., Shadows andSubstance: The Chem”cal Weapons Convention (Boulder, CO: Westview Press, 1993), p. 297.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation 47ularly given the fact that the Iraqis did notnormally care about environmental protection. 9oThus, while plant emission controls would reducechemical signatures outside the plant, the presenceof scrubbers and other air-cleaning systemswould provide a clue that toxic agents were beingproduced.Still, while special containment measuresmay provide a telltale sign of CW agentproduction, they are by no means a foolproofsignature. First, the pressurization of a facilitycan be reversed by changing the direction of airflow, perhaps in a deliberate attempt to deceive aninspection team, although this capability must bedesigned-in. Second, as the chemical industry hasadapted to increasingly stringent environmentaland occupational-safety laws, ordinary chemicalplants have increasingly adopted sophisticatedair-treatment systems and corrosion-resistant materials,blurring the distinction between CWcapableand commercial facilities. As a result,equipment designed for commercial purposesmay provide adequate containment for CW-agentproduction .91Conversely, a lack of stringent safety measuresis not a foolproof indicator that a countryis not producing CW agents, since a ruthlessgovernment that does not care about thewelfare of workers might fail to take such basicprecautions. Although the German Governmentargued that the chemical plant sold to Iraq by theKarl Kolb firm was not suitable for CW productionbecause it lacked adequate safety equipment,the real reason for the lack of safety measures wasSaddam Hussein’s willingness to tolerate a highincidence of injuries and deaths among the plantstaff. Iraqi officials later admitted to UN inspectorsthat there were about 100 accidents per yearinvolving chemical agents, 10 of them major. 92Finally, the advent of binary chemical weaponsmeans that it is no longer necessary tomanufacture supertoxic agents to acquire aCW capability. Instead, a production plant couldmanufacture DF, the immediate precursor of theG agents, which is no more toxic than manycommercial organophosphorus pesticides. Such aplant would not require high levels of containmentand hence could be more easily disguised.WASTE TREATMENT AND DISPOSALChemical weapon producers have been knownto dispose of their highly toxic wastes in anenvironmentally reckless manner. After WorldWar II, the Soviet Union and other countriesdumped large quantities of nerve and mustardagents at sea in metal barrels that have nowcorroded, posing a serious threat to the marineenvironment. The Soviets also dumped vastquantities of toxic wastes from CW agent productiondirectly into rivers. In the aftermath of theGulf War, Iraq destroyed large quantities ofchemical munitions it had failed to declare bypouring the toxic agents into standing ponds orholes dug in the ground, and by open-air burning.93Nevertheless, countries with greater concernabout protecting the environment might equip aCW agent production plant with more extensivewaste-treatment facilities than a typical commercialplant. Such facilities might include tanks forthe storage of toxic wastes and a treatment unit toneutralize acid byproducts with alkaline chemicalsand to detoxify and remove phosphoruscompounds. After treatment, the neutralizedwastes might be reduced by evaporation orincineration, and then disposed of in ways thatmight be observable. For example, waste lagoonsare quite conspicuous because of their size and90 1‘Report on German ‘Ikcimology in ‘Diyala’ Gas Lab,” Stern, Feb. 7,1991, pp. 29-33; translated in FBIS-WEU-91-032-A, Feb. 15,1991,p. 9.91 Buck and Flowerree, op. Cit., footnote 14, p. 13.92 Chemica[ Weapons Convention Bulletin, op. cit., fOOtnOte 50, p. 16.93 Peter Grier, “UN Inspectors in Iraq Get Chemical Surprise, ” Christian Science Monitor, June 23, 1992, pp. 1,4.

48 I Technologies Underlying Weapons of Mass DestructionFigure 2-4-Production Facility ObservableL————.—- J/d‘T-r-rT--u( \J,Onsite plant’s observables-Equipment/rain runoff-Spills-Air emissions deposited on groundI-Onsite-O ffsiteSOURCE: System Planning Corp., Chsmiea/ 14@apons Convent/on (CWC) S~naturas Ana/ysis, Final TeehniealReport No. 1396, August 1991, p. 61.because phosphates promote algal and bacterialgrowth, which would be visible in overheadphotographs. (However, some legitimate chemicalplants have lagoons situated near agriculturalland, where fertilizer runoff may cause similaralgal blooms during the summer months.) Anotherdisposal method involves injection of toxicwastes into deep underground wells. Since deepwells are hard to dig and would have to be quitelarge, they might be difficult to conceal. 94 Thewaste well at the U.S. Rocky Mountain Arsenal,for example, was 12,000 feet below the surface.CHEMICAL SIGNATURESThe goal in collecting and analyzing samplesduring on-site inspections of chemical plants andsuspect facilities is to detect signatures of illicitCW production; at the same time, it is importantto minimize the potential for false alarms and tolimit the disruptive effects of sampling on thecommercial chemical industry. Phosphorusmethyl(P-CH 3) bonds are characteristic of nerveagents, are rare in most organophosphorus pesticides,and are extremely resistant to degradationand hence persist for long periods in the environment.The phosphorus-fluorine bond found insarin and soman is also unusual, and its detectionin a commercial pesticide plant would warrantfurther investigation.Chemical signatures may be detected from avariety of sources. (See figure 2-4.) Inspectorsgiven on-site access to chemical facilities underthe terms of the chemical Weapons Conventionwill be allowed to take wipe samples from thesurfaces of process and pollution-control equipment,as well as liquid samples from the productionprocess and the waste stream. Even if thereactors and pipes are flushed clean prior to aninspection, the production of CW agents wouldleave behind traces of agents, precursors, andbyproducts that are absorbed into rubber seals andgaskets, which are too costly to replace frequently.The concrete floor of a plant alsoprovides an absorbent matrix for leaked chemicalsand is a potential reservoir of CW agentresidues. Analyzing such samples with sensitiveM st~wo~ ~te~tion~ Peiim Research Institute, op. cit., footnote 85, p. 293

Chapter 2–Technical Aspects of Chemical Weapon Proliferation | 49analytical techniques such as combined gaschromatography/mass spectrometry should thereforereveal the presence of telltale chemicals. (Seeapp. 2-A.) Nevertheless, such sampling andanalysis may be constrained by the amount ofaccess provided during an onsite inspection.| Detecting Clandestine ProductionDetection of clandestine CW agent productionin a nondeclared facility would require noncooperativedata collection by human agents or bycovertly emplaced or remote sensors, whichmight then be used to cue a challenge inspection.While detection of a clandestine productionfacility would be difficult, some possible signaturesare discussed below.EFFLUENT ANALYSISA number of approaches rely on the monitoringof plant effluents to detect clandestine CW agentproduction at a distance. One such approach is touse computer atmospheric models to predictwhere gaseous plant emissions are most likely tobe deposited on the ground, and to take soilsamples from such locations for analysis. Becausethe atmospheric models are imperfect,however, the effluent sample may be too dilute tobe identified.Near-site monitoring techniques, such as laserspectroscopy, are also under development fordetecting telltale chemicals in the exhaust plumesrising from chemical plant stacks without theneed to obtain access to a plant site. Suchtechnologies include both passive spectroscopicsystems that detect and analyze radiant emissionsat multiple wavelengths, and active systems thattransmit laser radiation at selected wavelengthsand then analyze the backscattered or emittedradiation. (See app. 2-A.) At present, near-sitemonitoring technology is not yet sufficientlysensitive or reliable for verification purposes.Part of the problem is that the quantity ofgaseous emissions from a chemical productionfacility is very site-dependent and is a functionof the plant’s emission-control systems and thequality of its maintenance.A third approach to detecting clandestine CWagent production is the analysis of liquid effluents.Since no chemical reaction is 100 percentcomplete, there are always some residual materialsleft over that may not be emitted as a gas andwill emerge in the waste stream. All methods ofCW production produce significant quantities ofwastes, although the exact amounts depend on thechoice of production process, the extent ofrecycling, and how rapidly the waste stream issent to a treatment facility. Flushing out theproduction line with a decontaminating solvent orwater also creates a liquid effluent that must bedisposed of. Analyzing such chemical tracesmay therefore provide a means of detectingCW agent production without gaining accessto the interior of a site. Nevertheless, effluentanalysis has a number of limitations:■ A proliferant may simply store productionwastes onsite or inject them into a deep wellrather than releasing them into the environment.A proliferant might also create aphoney waste stream to mislead monitors,who would not be able to detect the real fateof the production wastes without access tothe interior of the plant.■ Once the waste stream has passed through atreatment facility, its characteristic chemicalcomponents may be destroyed.Since a handful of commercial products(pesticides and fire retardants) break down tomethylphosphonate, the same final degradationproduct as nerve agents, merely identifyingthis compound in the waste streamwould not in itself provide conclusive evidenceof a violation.■ If the plant effluent were discharged into ariver, one would have to obtain water samplesclose to the source before the chemical signatureswere diluted to undetectable levels.For a detailed discussion of effluent analysis,see appendix 2-A.

50 I Technologies Underlying Weapons of Mass DestructionBIOMARKERS IN PLANT WORKERS ANDWILDLIFEYet another approach to monitoring makes useof the natural ecosystem around a chemical plantas a long-term collection mechanism. In recentyears, occupational health specialists have identifieda number of “biomarkers” associated withexposure to toxic chemicals such as pesticides.Living plants and organisms (including humans)tend to concentrate various trace chemicals intheir tissues, so that measurable quantities can bedetected in the higher members of the food chainliving in the vicinity of a suspect facility. Entiresmall organisms (e.g., insects), samples of animalfur, urine, blood, or feces, or plant leaves, flowers,fruit, or roots, could be analyzed to identifychemical compounds not normally present in thelocal environment. 95 Such an approach mightprovide more comprehensive coverage than pointdetectors.A related approach is to collect samples oftie, blood, skin, or hair from chemical plantworkers and analyze them for telltale biomarkersof covert CW production. One might look eitherfor metabolizes of sulfur mustard and nerve agentsin body fluids such as blood and urine, or for‘‘adducts’ of mustard or nerve agents bound tocellular DNA. (See app. 2-A.) In the UnitedStates, however, such monitoring might be considereda violation of Fourth Amendment protectionsagainst intrusive personal searches if it wereconducted without a warrant, and other countriesmight simply refuse to allow it.| Storage of Agents and MunitionsAlthough CW munitions are indistinguishableat a distance from conventional munitions, theymay be stored in bunkers that have distinctivecharacteristics. In Iraq, CW storage bunkers werelocated inside ammunition-storage depots butwere secured separately with fencing or barbedwire, set off in remote locations, and spaced farapart. Before the start of the Coalition bombingcampaign during Operation Desert Storm, however,the Iraqis moved many of their chemicalmunitions out of the storage bunkers and buriedthem in the desert to protect them from attack.The Iraqis also constructed decoy bunkers intendedto mislead enemy bombers. Thus, storagebunkers may not be a reliable signature ofeither the presence or the absence of a CWcapability.Of course, the discovery of stockpiled chemicalmunitions would provide a clear indication of aCW capability. Artillery shells and rockets containingCW agents, high explosives, or smokerounds are identical in shape, however, and differonly by an external color code that could be easilypainted over. Since chemical munitions are impossibleto distinguish by visual inspection alone,a proliferant country might attempt to violate theChemical Weapons Convention by painting chemicalmunitions to look like high-explosive shellsand storing them in the same depot.In order to characterize the contents ofsealed munitions while avoiding the hazards ofdirect sampling, several nondestructive evaluation(NDE) methods are under development.One such method, known as Portable IsotopeNeutron Spectroscopy (PINS), was developed bythe Idaho National Engineering Laboratory. Thistechnique involves irradiating a shell with neutrons,which interact with the chemical contentsof the munition to produce garoma rays that areunique for each chemical element. Nerve agentsare rich in phosphorus and mustard agents inchlorine, while high explosives contain largequantities of nitrogen but no phosphorus, chlorine,or arsenic. As a result, the gamma emissionspectra for CW agents and high explosives areeasily distinguishable. Although the PINS techniquehas shown a 95 percent accuracy rate intests on known chemical shells, its reliabilityunder uncontrolled field conditions has not yet93 sylv~ ‘IMmage and Barbam Waho~ ‘‘SXI@ Mammals as Environmental Monitors,” Oak Ridge National Laboratory Review, vol. 25,No. 1 (1992), pp. 55-57.

—Chapter 2–Technical Aspects of Chemical Weapon Proliferation | 51been demonstrated conclusively. 96 Several otherNDE systems are also under development andhave differing strengths and weaknesses. 97 Forexample, acoustic resonance spectroscopy usessound waves to assay the contents of a shell. It hasthe advantage of being able to complete an assayin 10 seconds, but the disadvantage of requiringthe acoustic signatures of known reference shellsof the same type.| Weaponization and Testing SignaturesWeaponization and testing of CW munitionsmay also provide signatures, although these, too,may be ambiguous.VISUAL SIGNATURESTest ranges for operational testing of chemicalmunitions and dual-use delivery systems such asartillery and missiles cannot be hidden undergroundor inside closed buildings, and hence mayshow up in overhead images. Such a test rangegenerally consists of a support area containingadministration and logistics and an experimentalarea containing a test grid and a large downwindsampling zone with an array of sampling poles .98Nevertheless, an illegal test facility might well becamouflaged and the tests conducted at night orwhen reconnaissance satellites are out of range.Observing a test might require considerable luck.Ground or aerial observations of militaryexercises involving chemical weapons mightprovide some clues to a country’s intentions, butthey are probably not a reliable signature. Oneproblem is that it is very difficult to understandthe purpose of a military exercise without knowingthe scenario that the planners are ruining.Exercises that involve the firing of munitions togenerate an aerosol might imply preparations forUltrasonic pulse echo apparatus to distinguishchemical munitions from conventional rounds. Noecho is observed if the shell is empty; echoes willreturn at characteristic times lf the shell contains asolid, liquid, or powder.offensive CW use, but they could also pertain tothe generation of smoke screens. Alternatively, aproliferant might conduct misleading field exercisesfor purposes of deception. Defensive anddecontamination exercises might also be part of abroader offensive strategy. And although fieldtesting is desirable, it is not an essential prerequisitefor acquiring a CW capability.DIFFICULTIES OF DETECTIONThe various signatures associated with theacquisition of a CW capability, along withpotential detection methods and countermeasures,are summarized in table 2-2. Overall, thechallenge of detecting and monitoring clandestineproduction of CW agents is a formidableone. None of the production signatures is areliable indicator by itself, and even combinationsof signatures may depend on making96 personal mmmticatio~ A. J. Caffrey, senior scientist, Idaho National Engineering Laboratory, Aug. 23, 1993.97 ~ addition t. p~s, ~~er N~rl.Des~ctive Evaluation (NDE) me~ods c~enfly ~der investigation include x-ray, aCOUStiC reSOIUUllXspectroscopy, ultrasonic pulse echo, laser acoustic spectroscopy, and ion-tube neutron spectroscopy. For a review of current NDE research anddevelopment, see the special issue of Verification Technologies devoted to this topic (LJ.S. Department of Energy, OffIce of Arms Control andNonproliferation, Verification Technologies, First/Second Quarters 1992).98 Sanches et al., op. cit., footnote 66, pp. S3-$$.

52 I Technologies Underlying Weapons of Mass DestructionTable 2-2—Chemical Weapon Program Signatures and ConcealmentProgram stage Signature Detection methods Concealment methods commentDesign and Scientific and technical Literature survey andengineering publications (presence analysisor absence)Acquisition of raw Patterns of feed material Monitoring of open-sourcematerials acquisition trade data; espionage1. Manage publication activities2. Use widely available technicalinformation rather than designnew agents or techniques1. Shuffle, divert acquisitions; mixwith legitimate uses2. Develop clandestine networks3. Produce known precursor chemicalsindigenously4. With chemical industry development,raw materials acquisitionsincreasingly lose their utility as asignatureClandestine productionplantSecurity MeasuresOverhead imaging or humanintelligence (humint)Conceal measures, or placeplant within other secure facilitiesEffluentsSampling of air, water, orsoil near suspect plant--various forms of chemicalanalysis1. Chemically alter effluents withdecontaminating solvents orthem with additives2. Hide wastes or remove for offsitedisposalConverted or multipur- Security Measurespose production plantEffluentsOverhead imaging orhumintSampling of air, water, orsoil near suspect plantsvariousforms of chemicalanalysis; laser remote sensingof emission plumesConceal measures1. Chemically alter or maskeffluents2. Remove wastes for offsitedisposalobservations in the right place and at the righttime. Major hurdles to detection include:the possibility of intermittent production ina small, pilot-scale facility;the low volatility of most of the compoundsof interest (resulting in low atmosphericconcentrations even insignificant leaks occur);masking and interference from legitimatechemicals produced at a typical multiple-usefacility;the political and economic costs of challengeinspections, which will severely constrainthe number of facilities that can be inspected;the difficulty of detecting production ofbinary agents, which are made from dual-usechemicals and widely available industrialalcohols.Despite the difficulties of detecting clandestineCW production, however, the cooperativeverification regime will be supplemented withnational intelligence-gathering efforts that mayprovide indications of CW-related activitiessomewhere along the acquisition spectrumranging from research through testing and thedevelopment of military doctrine. (As an illustrationof the contribution of national intelligenceefforts, Box 2-A recounts press reports describinghow the United States tracked the Libyan CWproduction facility at Rabta.) These additionalsources of information should increase the chancesof detecting a clandestine CW program, and could

i .Chapter 2–Technical Aspects of Chemical Weapon Proliferation | 53Program stage Signature Detection methods Concealment met hods commentSpecial safety and containmentmeasuresOnsite inspection of suspectplants1. Sacrifice worker safety2. Modern chemical plantsincreasingly have these featuresRare chemical processes(e.g., alkylation or cyanation)Onsite inspection of suspectplantsAlternate weapons agent productionwith commercial productionrequiring same processesCorrosion-resistant reactorsand other fittingsOnsite inspection of suspectplants; tracking of importsof such parts1. Replace corrodible equipmentas needed2. Trend is toward use of suchparts in legitimate commercialprocessesTell-tale residues within plantOn-site chemical analysis ofabsorbent parts (or removal foroff-site analysis)1. Use decontaminating solvents2. Practice quick replacement ofsuch parts as rubber flangesand seals that might absorbresiduesBiomarkers in plantworkersAnalysis of urine and bloodsamplesPrevent collection of samples un-Iess specifically permitted by challengeinspection regimeWeapon assemblyUniquely configured arsenals(e.g., distribution of storagebunkers)Overhead imagingPattern facilities after conventionalarsenalsWeapon testingUniquely configured testfacilitiesOverhead imaging1. Make special featurestemporary2. Test on overcast days, at night,or in absence of imaging devicesSOURCE: Office of Technology Assessment, 1993.be used to trigger challenge inspections under thetreaty regime.ALTERNATIVE PROLIFERATIONPATHWAYSThere are two basic approaches to acquiring anindigenous CW production capability:■ build a dedicated CW agent production plant(open or clandestine);■ convert existing chemical facilities (singlepurposeor multipurpose) to CW agentproduction on a temporary or permanentbasis. 99In the past, proliferant countries seeking a CWproduction capability have purchased turnkeyplants from foreign suppliers. For example, bothLibya and Iraq purchased entire chemical plantsfrom German firms that were then converted toCW agent production. Increasingly, however,proliferants purchase parts and engineering knowhowfrom a variety of sources and integrate themon their own. This new approach to acquisitionmakes it more difficult to halt CW proliferationthrough export controls.Proliferant countries-particularly those thatsign and ratify the Chemical Weapons Convention-~ A Prolifermt might al.so purchase bulk or weaponized CW agents from a state that already possesses them. This appmch is ~ely to beat most temporary, however, since the purchasing state would remain dangerously dependent on the supplier.

54 I Technologies Underlying Weapons of Mass Destructionare most likely to produce CW agents in aclandestine manner to avoid provoking internationalpolitical and economic sanctions. Nevertheless,a country that has been threatened orattacked by a more powerful neighbor may seekto acquire a CW capability as quickly as possible.This scenario would be compatible with themanufacture of cheap, low-stability agents fornear-term military use and might involve acquiringthe capacity for rapid but not necessarilysecret production in wartime. Such a‘ ‘breakout’capability might either be built deliberately inpeacetime or improved in response to a militarycrisis.| Building a Dedicated PlantThe advantage of building a clandestine CWplant on a new site is that it can be built in anisolated location, far from commercial chemicalplants that might be subject to routine inspectionsunder the Chemical Weapons Convention. 100 Thenumber of plant personnel could be kept to aminimum for security reasons, and specializedconstruction and camouflage procedures could beused. On the other hand, siting a dedicated CWproduction facility in the midst of a large commercialindustrial complex would have the advantagethat the surrounding ‘‘noise” would drownout any telltale CW-related signatures. Moreover,the construction of a clandestine plant at anisolated site, if detected, would tend to drawattention to the facility.Another strategy for a proliferant countrywould be to acquire one or more pilot-scalechemical plants and use them to accumulate, overa period of years, enough CW agent to be a potentstrategic asset in certain regional conflicts. l0lBecause of their small size, pilot-scale facilitieswould be easier to conceal. Nevertheless, stocksof agent produced over a long period of timewould have to be of greater purity to ensure anadequate shelf-life. This requirement would inturn demand distillation and the use of stabilizers,complicating the production process.| Converting an Existing PlantAn alternative pathway to acquiring a CWcapability would be to convert all or part of adeclared commercial facility to CW agent production.Experts disagree over the speed withwhich a commercial plant could be converted.Former CIA director William Webster allegedthat the Libyan Pharm-150 plant at Rabta wascapable of CW agent production but that ‘‘withinfewer than 24 hours, it would be relatively easyfor the Libyans to make the site appear to be apharmaceutical facility .’’ 102 Reportedly, this potentialfor deception was one reason that theUnited States turned down an offer by Libyanleader Muhamar Khadafy to do a one-time onsiteinspection of the plant. 103Some analysts challenge the assumption that itwould be easy to convert a commercial chemicalplant to the production of CW agents by simplychanging valves or piping. 104 First, only a fewtypes of chemical plants are suitable for conversionto production of nerve agents. Fertilizerplants use a different kind of phosphorus (phoslmMost comm~i~ chemical plants in the developing world are located in populated areas. Even if a commercial plant is initially built ina remote locatiow the resulting employment opportunities and economic activity tend to attract large numbers of migrants to the immediatevicinity.101 Ro~fi C. GOU~ Smdia National Laboratory, ~rSOnd Communication 1992.102 ~s~ony by w7ill~ H. Webster, D~ctor of Central ~tellig~~, h U.S. Semte, Committee on Governmental Al%@, G/obd $Veadof Chenu”cal and Biologica/ Weapons, IOlst Congress, Ist Session, Feb. 9, 1989 (Washington DC: U.S. Government Printing CMt3ce, 1990),p. 13.los ~ohy, op. cit., foomote 7C! P. 10.104 Much of he follotig ~ysis is based on research conducted by Alan R. Pittaway and the Midwest Research Institute in the late 1960sand early 1970s. See Midwest Research Institute, The Dlficulty of Converting Pesticide Plants to CWNerve Agent Manufacture, RchnicalReport No. 7 (Kausas City, MO: Midwest Research Institute, Feb. 20, 1970).

Chapter 2–Technical Aspects of Chemical Weapon Proliferation | 55phate) chemistry, do not contain most of thenecessary equipment for the chemical synthesisof nerve agents, and lack stringent safety andcontainment measures. Pharmaceutical plants sharemany precursors with CW agents, but the scale ofdrug production is generally much smaller thanthat of other specialty chemicals. Organophosphoruspesticide plants are most suitable for conversionto nerve-agent production, since the phosphoruschemistry is similar and much of theprocess equipment is of the type and capacitysuitable for large-scale production of nerve agents.In 1987, for example, the United States producedat least 5,000 pounds of each of 204pesticides, of which 33 were organophosphoruscompounds. Of the 33, six were alkylated, makingthem structurally similar to nerve agents andhence of greatest concern. Those six alkylatedpesticides were produced at 24 plants owned by17 companies. 105 In recent years, however, thetrend in pesticide development—at least bycountries not seeking to produce nerve agents—has been to move away from alkylated compoundsto those with reduced mammalian toxicity.As a result, ever fewer pesticide plantstoday are equipped with processes that can bereadily converted to nerve-agent production,although a proliferant could opt deliberatelyfor an old production method.In addition to pesticides, a handful of commercialorganophosphorus compounds are structurallyrelated to nerve agents, including flameretardants, plastics, and fuel additives. Volume ofproduction for the most significant of thesecompounds, the fire retardant dimethyl methylphosphonate(DMMP), is on the order of 2,200metric tons annually among four producers worldwide.l06 Thus, the manufacture of DMMP andrelated compounds could still be used as acover for nerve-agent production.The technical hurdles involved in converting acommercial plant to CW agent production aredifferent depending on whether the commercialfacility is single-purpose or multipurpose. Bothpathways are discussed below.SINGLE-PURPOSE PLANTSingle-purpose chemical plants are generallycustom-designed and optimized for production ofone product in vast quantities. As a result,converting such a plant to some other form ofproduction can take months. The German pharmaceuticalfirm Bayer, for example, spent 2 yearsrebuilding a single-purpose facility so that itcould produce two different but related chemicals.After this initial investment, the plant couldalternate between the two products with a changeovertime of 3 to 4 weeks. 107The differences in the chemical synthesis ofcommercial organophosphorus compounds andnerve agents mean that some of the processesand equipment are not easily convertible, butothers are. For example, pesticide plants do notnormally contain equipment for performing thecyanation reaction needed for tabun; the alkylationreaction needed for sarin, soman, and VX; orthe fluorination reaction needed for sarin andsoman. Thus, the presence of any of these processsteps in a pesticide plant would warrant furtherinvestigation. Pesticide plants normally havedistillation equipment that consists mainly ofstripping columns, which are not adequate fordistilling nerve agents like sarin or soman. 108(Distillation is only needed, however, if a long105 me ~~ ~c~ticide~ ~i~ a p.~1 bond tit were produced ~ he past ~ he u~ted states were: 2-chloroethy]phosphonic acid, Fonophos,Fosrnine ammonium, Glyphosate and its isopropyhirnine salt, and Trichlorfon. lbday, Fonophos is the only allqdated pesticide still producedin signitlcant quantities. See Stanford Research Institute International, Directory of Chem”cul Producers USA (Menlo Padq CA: SRIInternational, 1988).ILM ~pf, op. cit., footnote 89, P. 280.lm Buck op. cit., footnote 33, p. 151.1m Ibid., p. 148.

56 I Technologies Underlying Weapons of Mass Destructionshelf-life is required.) Moreover, pesticide plantsdo not normally use hydrogen fluoride-a keyingredient of sarin and soman-and generally usephosphorus oxychloride (POCl 3) or phosphoruspentasulfide (P 2S 5) as a starting material ratherthan phosphorus trichloride (PCl 3). Since phosphoruspentasulfide is not suitable for use inalkylation reactions, it cannot be utilized as astarting material for nerve-agent production. l09For these reasons, converting a pesticideplant to nerve-gas production would meanmodifying the production process and stretchingthe operating conditions to obtain reasonableyields while still maintaining secrecy. Accordingto one assessment, for example, ‘‘theconversion of a parathion plant to the productionof G-agents would be extremely difficult, requiringsubstantial material changes and plant retooling.‘’110 The modifications would involve reroutingpipes, valves, and mechanical seals to meetminimal operating requirements. For example, aproliferant might design a plant to produce anorganophosphorus pesticide that lacks a phosphoruscarbonbond and then change the feed materialsand process equipment to add a final alkylationstep-either in a clandestine section of the mainplant or at a separate location. It would also bepossible to design a plant that could make nerveagents and then add on “bypass piping to permitthe commercial production of pesticides andpharmaceuticals. Thus, in time of need, it wouldbe easy to convert the plant back to nerve-agentproduction.Conversion to nerve-agent production mightalso require upgrading safety, containment, andwaste-disposal procedures, although as has beenstated earlier, such signatures can be ambiguous.Converting a single-purpose pesticide plant tonerve-agent production would require at leastseveral weeks and would involve the followingsteps: design of the modified production line,acquisition of the needed equipment, andconstruction, checkout, and pilot operation.The actual time requirements would depend onthe experience of the plant personnel, the prioritygiven the project, and willingness to cut cornerson worker safety and environmental protection.Conversion time might be reduced by cannibalizingequipment from other plants or by employingused equipment, but the lack of integratedsafety systems would probably result in seriousaccidents and deplete the skilled workforce neededto run the plant. According to one analyst,‘‘Unless the plant had been designed for convertibilityin the first place, the first victims of theconversion would be the production workers.’111It would also be difficult or impossible to cleanout the pipes, pumps, and reactors well enoughafter CW-agent production to deceive an onsiteinspection. For all of these reasons, it wouldprobably be simpler to build a dedicated CWagent production facility than to convert anexisting single-purpose plant. 112MULTIPURPOSE PLANTA multipurpose plant would be easier toconvert to production of nerve agents than asingle-purpose plant. Multipurpose plants arecommon in the specialty chemical industry, andthey are also operated by subcontractors known as“toilers” or custom producers who make smallbatches of chemicals for larger companies that donot want to invest in special equipment for thispurpose. For this reason, multipurpose plants aredesigned for maximum flexibility. Process units,heat exchangers, and storage facilities are connectedby extra pipes that can be linked in variousconfigurations to manufacture several differentKM pit~way, op. cit., fOOtnOte ’20.110 ~pf, Op, Cit,, foomote 89, P. 2~0111 Rob~om CCChernicSJ weapons Proliferatiotq” op. cit., footnote 8, p. 26.112 Alan R. Pittaway, “An Approach to the Problem of Impeding for Organophosphorus Chemical Munition Production, Transportationand Storage” (Booz-Allen Applied Research, Inc., August 1%8), p. 14.

Chapter 2–Technical Aspects of Chemical Weapon Proliferation | 57chemicals over the course of a year. 113 Theequipment is generally designed to handle highlycorrosive chemicals. Some process equipmentmay be kept on pallets to minimize conversiontime, and quick-cleaning features and sophisticatedelectronic controls permit rapid rearrangementof components. Because of the complexityof a multipurpose plant, its operation requireshighly skilled engineers and other experiencedpersonnel.Today, modem multipurpose facilities capableof short-term, small-batch production are not thenorm in developing countries, where the greatmajority of companies produce large volumes ofa few commodity chemicals. As a result, there arefew multipurpose plants in the developing worldthat could be reconfigured. Nevertheless, thetrend in the worldwide chemical industry is tobuild more multipurpose plants as a means ofadjusting to rapid changes in production technology.Such a plant might therefore have theequipment needed for nerve-agent manufacturedistributed among its various production processes.If a multipurpose plant were designed forrapid conversion from one chemical process toanother, it might be possible to switch over ina few days with little chance of being detected.Even so, a plant specifically designed for rapidconversion from commercial to CW-agent productionwould be costly to build (on the order of$150 million), and would require a high level oftechnological know-how in plant design, engineering,and operation, and a skilled constructionworkforce. Design and construction would takeabout 4 years in most parts of the developingworld.A dual-use plant designed for rapid conversionwould also require stringent cleaning measuresfor the final steps in the production process toprevent the contamination of commercial productsparticularlypharmaceuticals-with deadly CWagents. Since seals on pumps and other materialhandlingequipment absorb chemicals from theproduction process, switching from production ofone chemical to another requires removing thepumps and cleaning them off-line, a timeconsumingprocess. In a rapidly convertible plant,however, the production line might be configuredwith modular pumps that could be removedquickly for cleaning and then replaced. Alternatively,two sets of pumps might be installed inparallel so that different chemicals could beproduced on the same line without contaminatingeach other. 114 Nevertheless, a plant that hasbeen specifically designed to facilitate rapiddecontamination would probably be uneconomicalfor commercial production, and wouldtherefore arouse suspicions on those grounds.| Binary Agent ProductionSome analysts have argued that binary weaponsmight accelerate CW proliferation by makingchemical weapons inherently easier and safer tomanufacture, store, transport, and use.115 Indeed,the relative lack of toxicity of the two precursorsmeans that production plants require less stringentcontainment measures. In the 1950s, forexample, the United States produced the binaryprecursors DF and QL in plants open to theoutside air and with relatively few safety precautions.Illicit production of binaries is also moredifficult to detect because the two chemicalcomponents have some legitimate commercial113 ‘CCMA}S O1sonUmve~~~Mcies of Ver@inga (2knica.1 Arms Treaty,” Chemical and Engineering News, vol. 67, No. 17, Apr. 24,1989, p. 8.114 ~t~im with Kyle OISO~ EAI COW., 1992.11S Br~ Ro~, ~~~fic~ ~p~~ents t. ~oliferation ~d B- ~oductioq” Bi~q Weapon$; Implications of the U.S. Chen”culStockpile Modernization for Chemical Weapons Proliferation, Report by the Congressional Research Service prepared for the Subcommitteeon International Security and Scientific Affairs of the Committee on Foreign Affairs, House of Representatives, Apr. 24, 1984 (WashingtonDC: Government Printing OffIce, 1984), p. 14.

58 I Technologies Underlying Weapons of Mass Destructionuses. A binary sarin weapon, for example, wouldconsist of two ingredients, DF and isopropanol,which react spontaneously to form the nerveagent. Yet dichlor-the immediate precursor ofDF—has legitimate commercial uses in fireretardants, insecticides, and plastics, and isopropanol(rubbing alcohol) is a common industrialchemical. Manufacture of these compoundsfor legitimate uses could thus be used as a coverfor the illicit production of nerve agents. Finally,binary weapons make it possible to use standardlogistics channels and less rigorous securitymeasures during production and transport, andthey have a relatively long shelf-life.I Trade-OffsFor a country seeking to develop a CWproduction capability, there are several majortradeoffs in the choice of proliferation pathway:SIMPLICITY V. VISIBILITYA proliferant faces a tradeoff between the useof a proven and relatively simple productionprocess for CW agents (e.g., conversion ofthiodiglycol to sulfur mustard) and the need toconceal its activities by using less well knownprecursors or procedures, thereby complicatingthe production process. Thus, a proliferant mustbalance the need for secrecy against the efficiencyand cost of production.SPEED V. VISIBILITYIf an aspiring proliferant faces a long-termadversary and seeks to acquire a strategic CWstockpile, it may seek to minimize visibility byinvesting the money and time needed to build adedicated clandestine plant. If the threat is moreimmediate, however, it may choose to convert anexisting commercial facility to CW agent production.SAFETY V. VISIBILITYA proliferant may seek to minimize the visibilityof a CW production facility by jury-rigging itfrom used equipment or items purchased frommultiple suppliers. The lack of an integrated plantdesign would result in more hazardous operation,however, increasing the occupational risks to theworkforce and the contamination of the environmentnear the plant. A reckless government mighteven deliberately accept a greater risk to itsworkforce or population in order to acquire a CWcapability more quickly or covertly, particularlyif it were a party to the Chemical WeaponsConvention.SIMPLICITY V. SHELF-LIFEThe sophistication of the production technologyrequired to manufacture agents depends onthe urgency of a country’s military requirements.If a country has no immediate need to use CWagents and plans to stockpile them for severalyears, the agents will require along shelf-life andmust therefore be produced with high purity. If acountry is producing nerve agents for immediateuse in battle, however, it can afford to make a lesspure product by eliminating the distillation step orthe use of stabilizing additives.AUTONOMY V. EFFICIENCYUsing an immediate precursor of a CW agent isobviously more efficient than using a startingmaterial that is several steps removed from thefinal product. Thus, while back-integration ofprecursor chemicals reduces a proliferant’s dependenceon outside suppliers, it also results ingreater overall complexity and cost, requiresmore workers to operate the plant, and results ina larger production complex to conceal and todecontaminate.

— —.Appendix 2-ATechniques forthe Detectionand Analysis ofChemical SignaturesThe Chemical Weapons Convention (CWC)permits the collection and analysis of samplesduring onsite inspections. Although the detailsof the sampling process remain to bedetermined by a Preparatory Commission that ismeeting in The Hague to negotiate the details of treatyimplementation, several analytical techniques may beused to detect and monitor chemical signatures associatedwith the illicit production of CW agents. Suchmethods could be employed either during onsiteinspections of declared chemical plants authorized bythe CWC or for near-site monitoring from the perimeterof a facility or from an overflying aircraft.Clandestine CW production facilities would first haveto be identified by intelligence assets and thensubjected to a challenge inspection before chemicalsampling could take place.The future international inspectorate to be establishedunder the CWC will require the establishment ofaccredited analytical laboratories that use certifiedtesting procedures for identifying CW agents, precursors,and degradation products. During onsite visits,inspection teams will use specified instrumentation forperforming in situ chemical analyses. To facilitate thedevelopment of such agreed instrumentation andprocedures, the Government of Finland has sponsoredsince 1973 the development of suitable analyticaltechniques. In recent years, this program has includeda series of international ‘‘round-robin” experimentsinvolving the analysis by laboratories in 15 countriesof unknown samples spiked with nerve and mustardagents, precursors, and degradation products. l Theparticipating countries have agreed that the presence ofcontrolled compounds will be confirmed with at leasttwo different instrumental methods of analysis, andthat the analytical laboratories will implement stringentquality-control measures.The difficulty of detecting CW agent signaturesis site-dependent and is a function of the sophisticationof a plant’s emission-control and decontaminationsystems and the quality of its maintenance.According to one analysis, the verification challengeranges in difficulty from the relatively simple task ofdetecting the production of treaty-controlled chemicalsin a large, single-purpose, stand-alone facility with arudimentary emission-control system to the muchharder problem of detecting telltale signatures at afacility equipped with an advanced environmental1 The participating countries in the Third Round-Robin ‘I&t were Australia, Canad~ C- the Czech and Slovak Federated Republic,Finland, France, Germany, Indi~ the Netherlands, Norway, the Russian Federation (two labs), SwedeG Switzerland, the United Kingdom, andthe United States (two labs). See Marjatta Rautio, cd., International Interlaboratory Compan”son (Round-Robin) Test for the Verification ofChemical Disarmament. F.3. Testing of Procedures on Simulated Military Facility Samples (Helsinki: Ministry of Foreign Affairs of Finland,1992).I 59

60 I Technologies Underlying Weapons of Mass Destructioncontrol system and embedded in a large multipurposechemical complex. 2Since the analytical techniques described below canreveal a considerable amount of information regardingthe operation of a chemical facility, verifying the CWCmust balance the intrusiveness needed to detect treatyviolations against the risk of compromising confidentialbusiness information unrelated to the treaty. 3 Inorder to minimize this risk chemical analyses forCWC verification will not involve an exhaustivecharacterization of samples but will focus instead onthe search for a specific set of known chemicalsassociated with CW production. Screening for a set ofknown target compounds poses less of a threat toproprietary information than would a complete chemicalanalysis of the sample. If one or more suspectchemicals were detected in the waste stream, however,a more in-depth analysis might be warranted.ONSITE INSPECTION TECHNIQUESDuring the production of a CW agent, traces ofvarious chemicals are released in vapor form from theplant’s smokestacks and ventilation systems and arealso absorbed by the seals and gaskets on pumps andother fittings, the agitator in the reaction vessel, andvarious rubber components and grease seals. Thus,during onsite inspections; of a chemical facility,inspectors might disassemble pumps and other piecesof equipment close to the production vessel, or takeswipe samples from inside the machinery, which is notlikely to be flushed clean by conventional decontaminationmethods. 4 In order to ensure that the samples donot degrade before being analyzed, inspectors must useproper sampling techniques (e.g., dry v. wet swipes).They must also determine whether actions have beentaken to preclude access to) possible samples, such aspainting over a stain on the floor.CW agents and precursors break down in theenvironment through the action of ultraviolet radiation(photolysis), water (hydrolysis), and air (oxidation),resulting in a series of degradation byproducts. Environmentalfactors such as sunlight, weather, temperature,and soil type can influence the rate of degradation.Dilution is another key factor affecting detectability:chemicals in effluents discharged into a river, forexample, may be diluted to undetectable levels a fewhundred meters or so downstream from the outflowpipe. 5Determining g the presence or absence of knownchemicals is generally performed with some variant ofa gas chromatograph/mass spectrometer (GC/MS), aninstrument that combines two analytical methods intandem. First, the gas chromatography vaporizes thesample and passes it through a packed column or ahollow glass capillary tube lined with a fine polymermaterial. Various substances in the sample takedifferent amounts of time to emerge from the tube,depending on their molecular weight and their attractionto the polymer lining. As they emerge from thechromatography, constituents of the sample are thenintroduced into a mass spectrometer, which breaksthem up into a compound-specific set of molecularfragments and then measures their masses very precisely.Sorting molecules first by their retention time in thechromatography and then by the masses of theirconstituent parts, GC/MS analysis can reliably identifyeach of several compounds in a sample. Such identificationis usually performed automatically by a patternrecognitionalgorithm, which tries to match the massspectrum of each component against a computerdatabase containing tens of thousands of referencespectra of known chemical compounds and comes upwith one or more candidates with specified probabilities.For purposes of CWC verification, considerableeffort has gone into compiling ‘‘libraries” of GC/MSspectra for CW agents, precursors, and degradationproducts.If the GC/MS instrument is calibrated correctly,it can confirm very reliably whether a given2 Jwes D. Bardem et al., Remote Sensing Technology and CW Am Control (Alexanti% VA: K~ Sciences Corp., Report No.P650-1254G-1, Feb. 2, 1993), p. ‘7.3 For ~ in-dep~ dis~ssionof this issue, see U.S. congress, OffIce of ‘Ikchnology Assessment The ChemicaZ Weapons Convention: ~flectson the U.S. Chemical Zndustry, O’TA-BP-ISC-1O6 (Washington, DC: U.S. Governrn ent Printing OffIce, August 1993),4“CMA’s Olson Unravels Intricacies of Verify@ a Chemical Arms Treaty,” Chenu”calund Engineenng News, vol. 67, No. 17, Apr. 24,1989, p. 9.5Albert Venveij et al., “Chemical Warfare Agents: VerMcation of Compounds Containing the Phosphorus-Methyl Linkage in WasteWater,” Science, vol. 204, May 11, 1979, p. 617.

Appendix 2-A–Techniques for the Detection and Analysis of Chemical Signatures | 61chemical is present in a sample at remarkably lowconcentrations, even in complex mixtures. Thedevice can detect substances in the parts per trillionrange, although the more complicated the mixture is,the harder it is to reach such high sensitivities. If thesample is being tested for the presence of a knownchemical, the detection limit will be much lower thanfor an unknown chemical. GC/MS is sensitive enoughto detect nerve-agent degradation products in wastewater even after extensive purification efforts. Empiricalresults also indicate that detectable traces of CWagents may persist for long periods after production. Inone trial inspection, traces of a carbamate pesticidewere found 2 months after production ended byanalyzing wipe samples from equipment and wastesamples, as well as air samples from warehouses andpackaging lines. 6Nevertheless, the extremely low detection thresholdsachieved in the laboratory may not be possiblein the field. GC/MS may not be able to identify tracequantities of agent with a high probability in thecomplex environment of a multipurpose chemicalplant, since other compounds unrelated to CW agentproduction may interfere with the analysis. In suchcases, visual inspection of the plant could help paredown the list of possible candidate compounds to thoseit would be technically feasible to manufacture in thatfacility.During an onsite inspection, special samplepreparationmethods may be necessary. For example,a water-soluble chemical may have to be convertedinto a derivative that is volatile enough to pass througha gas chromatography. It may also be necessary to try toextract the target compounds from a more complexmixture or from an absorbent material such as concrete,although such custom extractions tend to bedifficult, time-consuming, and expensive. Some nerveagentprecursors, for example, absorb tightly toconcrete and are only released by strong acid treatment.In addition to GC/MS, a gas chromatography can becombined with other types of detectors to performspecific analytic tasks. For example, a flame photometricdetector can identify the presence of sulfur orphosphorus in a sample with high sensitivity, while anelectron-capture detector can identify fluorine andphosphorus-containing compounds. GC/MS can becomplemented with other methods of chemical analysis.For example, high-performance liquid chromatography(HPLC) is useful for separating polar, nonvolatilecompounds, Bioassays such as the acetylcholinesterase-inhibitiontest can detect nerve agents atvery low concentrations through their ability toinactivate the enzyme acetylcholinesterase involved inneuromuscular transmission. Antibody-based techniques,such as the enzyme-linked immunosorbentassay (ELISA), rely on the ability of monoclinalantibodies to detect trace quantities of target compoundswith high sensitivity, although their specificitymay be relatively poor. Monoclinal antibodies havebeen produced for most of the major CW agents. 7Finally, research and development is under way onbiosensors, in which binding of the target compoundto specific antibodies or cellular receptor moleculestriggers an optical, physical, or electrochemical changethat can be converted into an electrical signal.In the hypothetical case of a whole new class of CWagents whose spectra are not already stored in acomputer database, one would have to use an analyticalmethod that provides detailed structural informationfrom which the identity of the molecule can bededuced. GC/MS can provide useful information aboutunknown compounds, such as their molecular weightand elemental composition. In addition, nuclear magneticresonance (NMR) spectroscopy is often used inconjunction with other techniques such as infrared andRaman spectroscopy to derive a molecular structurefor unknowns. Nevertheless, structure determinationwith NMR requires a fairly pure sample in themilligram range, many orders of magnitude greaterthan the minimum concentration at which a knowncompound can be detected with GC/MS. 8c Gordon M. Burck+ “Chemical Weapons Production Technology and the Conversion of Civil pmductiom” Arms Control, vol. 11, No. 2,September 1990, p. 141.7C. N. Lieske et rd., “Development of an Antibody that Binds Sulfur Mustard,” Proceedings of the 1991 Me&”cal Defense BioscienceReview (Fort Detrick MD: U.S. Army Medical Research Institute of Chemical Defense, Aug. 7-8, 1991), pp. 131-134.8Manuel Sanches et al., Chemical Weapons Convention (CWC) Signatures Analysis (ArlingtoxL VA: System Planning Corp., FinalTwhnical Report No. 1396, August 1991), p. 23.

62 Technologies Underlying Weapons of Mass DestructionChemical SignaturesSulfur mustard breaks down in the environment intothiodiglycol and two impurities, thioxane and dithiane,which can be identified as signatures of mustardproduction. 9 Most nerve agents (e.g., sarin, soman, andVX, but not tabun) contain a phosphorus-methyl(P-CH 3) bond that is difficult to break it remains intactafter chemical treatment and can only be destroyed byaggressive treatments such as high-temperature incineration.l0 These nerve agents break down in the wastestream into methylphosphonate (which contains thephosphorus-methyl bond), whereas most organophosphoruspesticides are degraded to phosphoric acid. (Seefigure 2A-l.)The durability of the phosphorus-methyl bondalso means that it can be identified for long periodsafter being discharged into the environment. Forthis reason, the phosphorus-methyl linkage is thusa good signature of illicit nerve-agent production.For example, soil samples taken in late 1992 frombomb craters near a Kurdish village in northern Iraq bya team of forensic scientists and later analyzed withGC/MS were found to contain degradation products ofsarin and mustard gas more than 4 years after thevillage was bombed by the Iraqi army in 1988. Thisfinding suggests that traces of CW agents or theirdegradation products can be detected after persisting inthe environment for long periods, provided that thesamples are taken from a point of high initialcontamination such as the center of a bomb crater. llChemical signatures associated with the productionof CW agents could also be obtained from samplingthe waste effluent stream of a production plant,although the samples would have to be collectedbefore significant dilution occurred. At the same time,little additional data would probably be derived fromvisiting the plant’s control room (where the relevantinformation could be hidden), sampling from theproduction line (which might interfere with production),or examining the plant’s books (which could beforged) .12 In order to ensure that the waste stream wasactually connected to the production line, however, theinspectors would have to be given unlimited access tothe plant’s waste-processing system.I Problem of False PositivesSince GC/MS analysis is so sensitive, it is unlikelyto yield “false negatives,” that is, to concludemistakenly that a sample contains no evidence of illicitproduction. However, the problem of ‘false positives”—unfounded suspicions of noncompliance-is moretroublesome, particularly with respect to early precursorsand final degradation products. In the case ofnerve agents, false-positives can arise if the plant ismanufacturing or using a legitimate compoundthat contains a phosphorus-methyl bond and thusbreaks down into the same degradation product asa nerve agent. Fortunately, only a handfull of commercialproducts contain a phosphorus-methyl bond,including the pesticide Mecarphon and the organophosphorusflame retardant dimethyl methylphosphonate(DMMP), which is also used as a plasticizer for vinylplastic and an intermediate in the production ofherbicides.Worldwide production of DW is spread among14 companies, 11 in the United States and 3 in WesternEurope. 13 According to one assessment, “A challengedfacility may claim it is producing a chemicalclosely related to a scheduled agent [CW agent orprecursor] which would result in emissions overlappingthose of the scheduled agent. As a result, someidentified chemicals may not be sufficiently unique forg Sanches et al., Analysis of Signatures Associated with Noncompliance Scenarios, Report No. DNA-TR-92-74 (Arlingto~ VA: SystemsPlanning Corp., January 1993), p. 59.10s= U.S. Congess, of fIce of WholoH Assessmen~ Disposal of Chenu”cal Weapons: Alternative Technol@v--Bm&Ound paPer~OTA-BP-O-95 (Washington, DC: U.S. Governm ent Printing Hlce, June 1992).11 Human Rights Watch “Scientific First: Soil Samples Thken From Bomb Craters in Northern Iraq Reveal Nerve Gas-Even Four YearsLater, ” press release, Apr. 29, 1993; Lois Ember, “Chemical Weapons Residues Verify Iraqi Use on Kurds,” Chemical& Engineering News,vol. 71, No. 18, Mlly 3, 1993, pp. 8-9.12 Stephen Black, Benoit Morel, and Peter M. ~Pf, “E laminating the Shadows: On-site Inspections and the Chemical WeaponsConvention” Benoit Morel and Kyle Olson, eds., Shadows and Substance: The Chem”cal Weapons Convention (Boulder, CO: Westview,1993), p. 19313 U.S. @artrnent of Commerce, Bureau of EXPOrt ~“ “ tratiom OffIce of Foreign Availability, Foreign Availability Review: 50 CWPrecursor Chemicals (//) (Washington DC: Department of Commerce, Nov. 8, 1991), p. 23.

Appendix 2-A—Techniques for the Detection and Analysis of Chemical Signatures | 63this particular plant. The same situation applies toillicit facilities embedded within larger relatedplants. ’’ 14Because methylphosphonate is resistant to furtherdegradation, it tends to accumulate in the environment,Background levels have therefore been increasinggradually in the rivers, lakes, and streams of industrializedcountries. For example, Albert Verweij andcolleagues in the Netherlands detected significantlevels of the compound in the waters of the Rhine andMeuse Rivers because of the upstream manufacture ofDMMP. 15 Such environmental background levels mayeither generate false-positives (unless they had beenpreviously measured) or, conversely, mask the actualeffluents from nerve-agent production. For this reason,the detection of trace levels of methylphosphonate inthe air, soil, or water near a chemical plant might notprovide unequivocal evidence of nerve-agent production.To solve the problem of false positives, it wouldbe essential to screen liquid and gaseous chemicalplantemissions for a specific set of target compounds.In addition to the CW agents themselves andtheir degradation products, this list would includeagent precursors and intermediate byproducts generatedat various steps in the manufacturing process, andtheir respective degradation products. The majorweaponized CW agents each have up to six differentsynthetic routes, requiring different sets of equipmentand precursor chemicals. Thus, a suite of targetcompounds could provide evidence for each of thesealternate production pathways. Identifying such suitesof chemical compounds in the waste stream wouldreduce the likelihood of false-negatives and falsepositives.Detecting traces of nerve agents themselves clearlyprovides the best evidence of illicit production. If theactual agents cannot be found, the next best evidenceis provided by primary degradation products and, ifpossible, both parts of the original agent molecule(e.g., the acid and amine components of VX). Thedetection of a secondary degradation product suchas methylphosphonate would not in itself constitute/s’\Figure 2-A-l-Chemical Warfare Agents andDegradation ProductsCH 2CH 2OH/CHCI-ICI ‘ s < C H c H o H2 222CH 2CH 2CIAThiodiglycol\ \ /sCH 2CH 2Sulfur mustard(dichlorodiethylsulfide)\CH 2CH, /\\ 1, 4-Dithiane/O—CHCH 3sJ4/\CH 2CH 2\CH 2CH 2/1, 4-Dithioxaneso/O—CH/- ‘\ HP / \cHH 3C–P —F CH 3—> H 3C–P–OH8Sarin (GB)II0CH 3lsopropylmethylphosphonicacidIH 2Ov’ OH/H 3C–P–OH1!Methylphosphonic acid(Methylphosphonate)SOURCE: Chemical and Engineering News, vol. 71, No. 18, May 3,1993, f). 8.314 s~ches et al., op. cit., footnote 9, p. 65.IS VeWeij et a]., op. cit., footnote 5, P. 617.

64 I Technologies Underlying Weapons of Mass Destructionstrong evidence of illicit production because it couldalso result from certain legitimate chemicals. 16Nevertheless, if methylphosphonate is detected in thewaste stream and plant officials seek to explain it awayby claiming pesticide or DMMP production, theinspectors could ask for supporting evidence in theform of samples and written records.| Circumvention ScenariosIn addition to the problem of false-positives, there isthe possibility of deliberate deception on the part of adetermined proliferant. For example, a country engagedin clandestine CW-agent production mighttake special measures to mask or otherwise concealthe presence of telltale chemical signatures in thewaste stream. 17 Indeed, a problem associated withsensors designed to detect trace quantities of chemicalsis that they can easily be swamped by related signals.Examples of some possible deception strategies include:Pumping chemical wastes from the plant intounderground storage tanks or wells, or into tankertrucks for disposal off-site.Setting up a phoney waste stream for samplingthat is unconnected to the actual production line.Continually recycling the waste stream to reducethe quantities of byproducts released.Using a decontaminating solution that reacts withtraces of illicit chemicals to form a product thatmay not be in the standard library of a GC/MS.This strategy has been termed “designer deconlamination.”18For example, the methyl phosphonatein the waste stream could be reacted withthionyl chloride and an alcohol to obtain a diester,which would not look anything like the originalcompound in a GC/MS analysis. Nevertheless,the use of an unusual decontaminating solutionwould be suspicious if’ nothing about the facilityjustified its presence; in addition, the samplecould be hydrolyzed during the analysis toregenerate the methylphosphonate.Diluting the release of a telltale byproduct such asmethylphosphonate in the waste stream so that itcan no longer be detected. In practice, theeffectiveness of this strategy would depend on thedetection limits of the analytical instrument,which for GC/MS can reach parts per trillion.Thus, achieving the necessarily dilution to evadedetection would require impractically large volumesof decontamination fluid.Flushing the production line with a decontaminatingsolution followed by a legitimate butclosely related commercial product to mask anyresidues of agent. This scheme would only bepossible if the plant were simultaneously producinga commercial compound containing a phosphorus-methylbond, such as an alkylated pesticide(e.g., methyl-parathion) or DMMP. A sophisticatedcheater, however, would almost certainlycouple the two operations.Passing production wastes through an ionexchangeresin to remove methylphosphonate;such resins are expensive but reusable.Developing a novel agent that is not in theGC/MS database. Russian scientists, for example,have reportedly developed a new type ofbinary nerve agent. 19 Such a scenario is unlikelyin most developing countries, however, since thedevelopment of an entirely new class of CWagents would require a costly investment inresearch, development, and testing. Modificationsof existing CW agents might be detected byprogramming the instrument’s computer to recognizea family of related agents.Some of these circumvention strategies might reducethe probability of detection. If, however, theywere performed after notification of a challengeinspection, they might be carried out hastily andcarelessly, resulting in spills or other accidents thatwould leave behind telltale traces of agent. The use ofunusual decontamination strategies might also raisesuspicions of a violation. Thus, such waste effluentlb ~a~~utio, ed,, Internafi’onal Inter-L.aboratory Compan”son (Round-Robi”n) Testfor the Verification of ChemicalDisarmame nt. F.l.Testing of Existing Procedures @Iclsinki: Ministry of Foreign Affairs of Finlan& 1990), p. 93.N S= Kathleen C. Bailey, “Problems With a Chemical Weapons BUS’ Orbis, vol. 36, No. 2, spring 1992, pp. 239-251.18 Ibid., p. 241.19 ‘*-y~ov,F~orov ~~/Russ~~~oductioU’ ‘Novoye Vremya, No. 44, October 1992, pp.4-9(~kcdti FBIs-sov-92-213,Nov. 3, 1992, pp. 2-7),

Appendix 2-A–Techniques for the Detection and Analysis of Chemical Signatures 165sampling techniques would be most effective whenused in conjunction with other forms of onsiteinspection.Searching for a suite of compounds (agents, precursors,and degradation products) on a target list wouldalso help defeat circumvention efforts, since thepattern of chemical signatures emitted by a plant couldnot be masked as easily as a single chemical. Indeed,the likelihood of masking all of the target compoundsassociated with a given production process would bevery low. Conversely, whereas a secondary degradationproduct like methylphosphonate may give riseto false-positives, the probability of an error declinesrapidly when the suspect chemical is found inconjunction with a suite of other target compoundsin the same manufacturing process.In sum, it remains an open question whether acarefully planned and executed deception aimed atillicit production of CW agents would be detected.Nevertheless, cheaters would probably not be sure theycould get away with the deception, and hence might bedeterred from trying. While one might theoreticallyconceive of a plant design that could circumventdetection, such a facility would probably differsignificantly from existing commercial plants andmight therefore arouse suspicion on those grounds.According to one analysis:In a multipurpose plant. . . industry wouldinvest significantly so that the interior of theactual production line could be easily cleaned inorder to enable quick product change; this wouldnot be the case for waste water channels, reactorventilation systems, off-specification lines and soon, which would be connected either to purificationstations or to equipment used to recyclecertain chemicals. It is there inspections wouldlook for traces of illicit production; if they weredesigned in such a way that they could easily andthoroughly be decontaminated, this would be aneconomically unfeasible and suspect effort bycivil industry .20NEAR-SITE AND REMOTE MONITORINGTECHNIQUESNear-site and remote monitoring of chemical signatureswill probably be carried out openly within thenegotiated terms of the Chemical Weapons Conventionand covertly as an intelligence operation. Covertsensors, by definition, could not be openly discussedthey would have to be made sufficiently reliable andrugged to permit long periods of unattended operationin a potentially hostile environment and cleverlydisguised to prevent detection and tampering. 21Near-site monitoring can be either real-time, meaningthat the concentration of a particular substance ismonitored continuously, or integrative, meaning thatonly the average or the cumulative amount over aperiod of time is recorded. Integrative monitoring canbe further subdivided into active and passive methodologies.Active-integrative systems pump air or waterthrough a filter over a period of days or weeks toconcentrate trace molecules for later analysis. Incontrast, passive-integrative systems simply absorband retain trace chemicals from the environment overa period of time, much like a sponge.I Air-Sampling SystemsActive air-sampling could be conducted either witha system on the ground in the vicinity of a chemicalplant, or based on an overflying aircraft. 22 There aretwo types of gaseous emissions from a CW productionplant: controlled smokestack emissions and“fugitive” emissions. Stack emissions are plannedreleases from the production process that have beenfiltered by the plant’s pollution-control system. Fugitiveemissions are uncontrolled releases that have notpassed through the pollution-control system, such asslow leaks from storage tanks, gaskets, and reactorpressure-release valves, or an accidental productionmJ. pm Robinson and RaLf Trapp, “Production and Chemistry Of MusWd GM,” S. J. Lund@ cd., Verification o~lluai-use Chem”cakunder the Chem”cal Weapons Convention: The Case of Thiodiglycol, SIPRI Chemical& Biological Warfare Studies No. 13 (Oxford, England:Oxford University Press, 1991), p. 15.21 F ranklin E. Walker, Technical Means of Vetifiing Chemical Weapons Arms-Control Agreements (WashingtorL DC: Foreign PolicyInstitute, Johns Hopkins University School of Advanced Lutemational Studies, May 1987), p. 15.~ m~ for FO@n ~fis Of F-d, Air ~Onitoring us a Meun,s for Veriflcafion of ch~ical Disarmmnt, VOIS. I-III (Heklki:Ministry for Foreign Affairs, 1985-1987).

66 I Technologies Underlying Weapons of Mass Destructionline rupture. Since the chemicals involved in CWproduction are not particularly volatile, fugitive emissionswould tend to stay closer to the ground, andmight be detected through real-time sampling atlocations near the production equipment. Moreover,fugitive emissions (e.g., from storage tanks or thewaste-treatment system) may persist even after a planthas been temporarily shut down.Air sampling involves collecting samples of airdownwind from a chemical facility and analyzing themfor CW agents, precursors, or byproducts; it can beeither real-time or integrative. In one approach,atmospheric contaminants could be pumped through atube packed with an absorbing substance (e.g., resinbeads), concentrated for a period of time, and laterdriven off by flash heating in an inert-gas atmosphereand identified with GC/MS or high-performance liquidchromatography. Air-borne chemicals may also adhereto dust particles or and maybe transported in dropletsof water vapor, raindrops,, or snowflakes. 23 In anexperiment conducted in Finland, 4 kilograms of anerve-agent simulant containing phosphorus werereleased into the atmosphere and subsequently identifiedin air samples collected 200 kilometers from therelease site. 24 The U.S. Army is also developingatmospheric monitoring systems to protect the publicfrom accidental leaks during the destruction of CWagent stockpiles.In the treaty-verification context, detection sensitivitiesfor air sampling are demanding for thefollowing reasons:■ Given the lethality of CW agents, productionplants usually incorporate high-containment featuresthat minimize emissions. The more modernthe plant design, the lower the level of fugitiveemissions and the more difficult detection becomes.Developing countries tend to impose lessstringent safety practices, but the extent offugitive emissions varies greatly from plant toplant. The trace amounts released into the atmospheremight not be concentrated enough to createan identifiable signal.The majority of materials involved in CW agentproduction that yield detectable signatures are notvery volatile even if a leak occurs, compoundingthe sensitivity problem.When air samples are taken over longer ranges,weather patterns can complicate efforts to identifythe source of detected emissions, since windmay shift the direction of the emission plume.Remote air sampling cannot pinpoint the sourceof a clandestine facility for challenge inspectionunless the sampling is conducted for extensiveperiods or happens to coincide with the release ofdetectable emissions, and unless an atmospheric-transportmodel can trace the contaminantsback to the facility of origin.Deliberate countermeasures might foil airsamplingefforts. A clever plant operator mightbe able to mask such releases, particularly if hehad prior knowledge of the monitoring technologies.Alternatively, a cheater who was aware hewas being monitored might control emissions ordiscontinue production while samples were beingcollected, or refuse permission for aerial overflights.Although fugitive emissions (e.g., fromstorage tanks) might continue in the absence ofproduction, they might not be concentratedenough to be detectable.Because of these factors, even in those instanceswhere detection has been accomplished by airsampling, the detection was made through extensivesampling grids during rather massive releases.This source is easy to extinguish simply by stoppingproduction. 25| Optical Detection SystemsAnother approach to the real-time detection andanalysis of chemicals released deliberately or accidentallyfrom a CW production facility is to use a remotespectroscopic system based on light scattering, absorption,or induced fluorescence. A combination of two ormore of these techniques may be needed to producen ~y Sfitin ~d ~c~el ~e~~ Smengthening the Chemical Weapons Convention Through Aen”alInspections, Occasioml Paper No.4 (Washingto~ DC: Henry L. Stimson Center, April 1991), p. 13.w WQ for ForelP ~~ of Fti~~ The Finnish Research Project on the Verification of Chemical Disarmament (Heh~: -Vfor Foreign Affairs, 1989), p, 13.2S RaPond R. Mc~e, Tr~ty Vefilcation pro~, Lawrence Liverrnore National bbOratOIy, W~Olltd cO-ticatiO% 1~.

Appendix 2-A—Techniques for the Detection and Analysis of Chemical Signatures I 67reliable results. 26 Remote spectroscopy can either be“passive,’ which analyzes electromagnetic radiationemitted by the sample or by background sources, or‘‘active, ’ which irradiates the sample with a laserbeam. For example, fourier transform infrared spectroscopy(FTIR) has been used to detect telltalechemical signatures in stack plumes or fugitive emissionsat ground level or at higher altitudes. Broadbandinfrared has the potential to identify a wide variety ofcompounds simultaneously.A closely related active laser sensing technique isknown as lidar, for “light detection and ranging, ”Whereas spectroscopes are generally broad-bandtechniques, lidar is laser-based and thus consists of asingle or a few distinct wavelengths. (As lasers becometunable, however, this distinction may disappear). Anadvantage of laser-based systems is that the power isfocused at a single wavelength rather than being spreadamong many, Differential absorption lidar (DIAL)uses two different wavelengths, one of which isabsorbed by the target molecule and one that is not.The difference between the absorbed and unabsorbedsignals is used to determine the target molecule’sconcentration. Another lidar technique, known asRaman spectroscopy, involves exciting a chemicalwith a monochromatic laser and measuring shifts infrequency that provide structural information. Water isnot a strong Raman absorber and thus causes littleinterference.Remote sensing of chemical-plant emissions maybeperformed on stack plumes or fugitive emissions atground level or at higher altitudes. In principle, theilluminating laser can be located on the ground ormounted on an aircraft, a remotely piloted vehicle, oreven a satellite. To characterize the chemical emissionsfrom a smokestack, the laser would be pointed eitherdirectly at the gaseous exhaust emitted from the stackor downwind along the effluent plume, and thereturned light picked up by a detector. Fluorescence orabsorption of light by the chemical compounds in theexhaust give rise to characteristic spectral bands.“Closed-end” optical detection systems employ amirror or separate detector to analyze the illuminatinglaser beam after it passes through the chemical plume.They are more sensitive than “open-ended” systems,which collect only light scattered back to a detectornear the laser source. The FTIR detector, underdevelopment for the Environmental ProtectionAgency, is an example of a closed-end system. Itemits a beam of infrared light across the plume, and alarge mirror then reflects the beam back to theemitter/detector system, doubling the path length andthereby increasing the sensitivity. After being processedthe resulting data yield the characteristic infraredabsorption spectra for the chemical species ofinterest. 27The success of optical remote-sensing techniquesdepends on a number of variables, however, including:■ the concentration of the target compound(s) in theplant emissions, which may be a function ofemission controls;■ the chemicals present in the background and theirconcentrations;■ the detection limits of the remote-sensing equipment.Current-generation systems are not sufficientlysensitive to detect trace quantities of agent. Forexample, lidar technologies are capable of detectingCW agent in air at concentrations of 1 to 10 milligramsper cubic meter. In other words, they are several ordersof magnitude less sensitive than existing analyticalinstruments used for onsite sampling, which have adetection limit of 1 to 10 micrograms per cubicmeter. 28 Experience has shown that the probability ofremotely detecting activities occurring within a manufacturingfacility is nearly zero if samples are collectedmore than a few meters from the building. Wasteeffluent streams are an exception to this rule, but evenhere samples must be collected before significant~ Kenne~ E. Apg LOS Alarnos National hboratory, “Near-Site Monitoring for Compliance Assessment of the Chemical WeaponsConvention” IACP-90-289, June 15, 1990.27 Ro~fl ~ntz et ~$, Chemical weapons (CW) TreaV Venflcafion Technology Research and Development: program Interim su??v)Mry(Aberdeen Proving Ground, MD: Chemical Research Development & Engineering Center, Report No. CRDEC-CR-124, September 1991),p. 24.28 Mmuel L, s~~hes, et ~.,A*/y~i~ of sig~ture$A~~ociared With Noncompliance sce~rios, Rq)ort No. DNA-~-92-T4 (Arlington, VA:System Pkmning Corp., January 1993), p. 96.

68 I Technologies Underlying Weapons of Mass Destructiondilution occurs. 29 Moreover, chemical plants in developingcountries do not now employ sophisticatedenvironmental protection devices, but as such equipmentbecomes more widely available, plant emissionscould be reduced significantly.Potential countermeasures also exist to remotesensingtechnologies. For example, a determinedcheater might reduce emissions below the detectionthreshold, or release masking compounds that absorbinfrared radiation at the same frequencies as do thetarget chemical species.| Sorbent MaterialsOne approach to passive-integrative monitoringinvolves the use of absorbent materials called “sorbents,’ which have a very large internal surface area.Airborne chemicals simply diffuse into the materialand are irreversibly bound to it, although they can laterbe extracted for chemical analysis. Examples ofsorbent materials include diatoms (porous, silicabasedstructures that are the microscopic skeletons ofplankton), zeolites (long-chain polymers of silicon,oxygen, and aluminum), and silica gels that have beenchemically modified to absorb organic chemicals butnot water.Conceivably, artificial rocks or gravel made of asorbent material could be dispersed in the vicinity ofa suspect facility. These sorbents would accumulatevolatile chemicals from the air over an extended periodof time, providing concentrated samples for laboratoryanalysis. 30 The drawbacks of passive-integrative systemsare the lack of temporal information about thetiming of effluent releases, plus the fact that chemicalagents may degrade in the natural environment orwithin the absorbent material.BIOMARKERS FOR CW AGENTSWartime or occupational exposure to CW agents canleave behind long-lasting traces in humans or otherliving organisms. These biochemical signatures, knownas “biomarkers,” might conceivably be monitored asa means of detecting illicit CW production or use.During the Iran-Iraq War, for example, chemicalanalysis of urine samples from Iranian soldiers attackedwith sulfur mustard revealed elevated levels ofthe metabolize thiodiglycol in most of the victims. Insome cases, however, the technique could not distinguishbetween control urines and samples of allegedlyexposed soldiers. To solve this problem, scientists atthe U.S. Army Medical Research Institute of ChemicalDefense developed a more sensitive assay that involvedchemically derivatizing thiodiglycol beforeconducting the analysis. 31 Using this method, levels Ofurinary thiodiglycol in individuals moderately exposedto mustard gas were found to be greater than 10nanograms per milliliter (10 parts per billion) for atleast a week 32 Similar techniques have been developedfor detecting the major metabolizes of nerveagents (methylphosphonate esters) in biological fluidsby converting them into derivatives suitable forgas-chromatographic analysis. 33 The advantage ofurinary metabolizes is that measuring them is muchless invasive than taking blood samples; the drawbackis that most organophosphorus compounds are clearedfrom the body within 48 hours of exposure.Another biomarker technique involves measuringthe activity of the enzyme acetylcholinesterase, whichis specifically inhibited by nerve agents. While thisenzyme is located primarily in nervous tissue, it is alsopresent in the blood-both plasma and red bloodm Rapond R. IVMhim, Op. Cit., footnote 25.~ W, l%rl, Los Alamos Natiomd Laboratory, “Speciabd Sorbents,” presentation at the Chemical Weapons Convention Verifkation‘Rchnology Research and Development Conference, Herndoq VA, Mar. 3, 1993.31 E. M. Jakubowski et al., ‘QwuXMcation of ThiOdiglycol in Urine by Electron Ionization Gas Clmxnatography-Mass Spectmmetry,”Journal of Chromatography, Biomedical Applications, vol. 528, 1990, pp. 184-190.32 E. M. Jakubowski et al., “Case Studies of Accidental Human Mustard Gas Exposure: Verifkation and Quantification By MonitoringThiOdyglycol Levels, ” Proceedings of the 1991 Med”caIDefenseBioscience Review (Fort DetriclG MD: U.S. Army Medical Research Instituteof Chemical Defense, Aug. 7-8, 1991), pp. 75-80.33 M. L. Shih et al., “Detection of Metabolizes of l’bxic A@hnethylphosphona&S in Biological Samples, ” Biological Mass spectrome~,VO1. 20, 1991, pp. 717-723.

Appendix 2-A–Techniques for the Detection and Analysis of Chemical Signatures | 69cells—although its function there is unknown. It ispossible to measure the activity of blood acetylcholinesterasecompared with known normal values (preferablywith earlier values from the same person or a setof normal values from several individuals); the effectsof nerve-agent exposure on the activity of the enzymeare detectable for up to 3 weeks .34 Measurements canbe made on small blood samples drawn from thefingertip. This technique has been used for routinehealth control of workers involved in production orspraying of organophosphorus pesticides, and it mightalso reveal the clandestine production of nerve agentsat a suspect production or storage facility. Nevertheless,the assay would not be able to distinguishbetween the illicit production of nerve agents and thelegitimate production of organophosphorus pesticidesor fire retardants in the same plant. It would also beessential to know the background (pre-exposure)levels of acetylcholinesterase activity.Yet another means of detecting exposure to CWagents involves the detection of “adducts” resultingfrom the binding of toxic chemicals directly tomolecules of DNA or protein in the body. Sulfurmustard, for example, forms covalent bonds withnucleotide bases along the DNA strand that maypersist for several days or weeks. The major DNAadduct produced by sulfur mustard is an alkyl groupbound to the nucleotide guanine, which accounts forover 60 percent of the DNA damage caused by sulfurmustard. 35 The DNA molecules can be extracted fromskin cells or peripheral white blood cells and analyzed.A group of Dutch scientists has also developedmonoclinal antibodies to alkylated guanine, making itpossible to use an immunoassay (ELISA) technique todetect adducts in DNA extracted from white bloodcells. This method is sensitive enough to detect oneDNA adduct among 10 8 unmodified nucleotides-alevel of damage resulting from exposure to a smalldose of sulfur mustard. 36Analysis of DNA adducts can reveal an individual’sprior exposure to toxic chemicals, and has already beenused to monitor occupational exposure to pesticidesthrough both the air and the skin. This technique mightalso be used to detect clandestine production of CWagents by plant workers at suspect facilities, althoughthere may be constitutional barriers to mandatoryblood testing in some countries. Monitoring of DNAadducts also has some technical drawbacks. Onlysmall quantities of adducts can be extracted fromaccessible tissue such as white blood cells, and DNAadducts tend to be removed by chemical and enzymaticprocesses and hence do not persist for long in the body,having a half-life of a few weeks.Because of the transience of DNA adducts,several investigators have turned instead to proteinadducts, such as the alkylation of hemoglobin bysulfur mustard. Experiments have shown that about1,000 times more sulfur mustard binds to proteins thanto DNA. 37 Moreover, hemoglobin has a relatively longlifespan (120 days), permitting the determination ofcumulative exposure to toxic chemicals over a periodof months. 38 Analysis of blood samples for hemoglobinadducts might therefore be the best way ofdetecting long-term exposure to CW agents in chemicalplantworkers. Nevertheless, the concentrations ofhemoglobin adducts are usually found at extremelylow levels (femtomoles or picomoles per gram),requiring measures that are extremely sensitive andselective. 39 Such testing therefore entails complextradeoffs among sensitivity, specificity, and cost.34 s. J. L~@ ‘ ‘me ~bition of chol~est~~e Activity by ~~ophosphorus compounds as a M- kl m h.lSpCCtiOIl hCK%dUR,” inStockhom International Peace Research Institute, The Problem of Chemical and Biological Wi@are, Vol. V: Technical Aspects of EarlyWarning and Verification (Stockholm: Almqvist & Wiksell, 1975), pp. 180-181.M David B. Ludl~ paula A. ~tc~e, ~d ~tig Hagopi~ “Systemic Toxicity of suh Mus~d: A predictive ~st B* on ~Measurement of DNA Adduct Formation in Peripheral Blood, ” Proceedings of the 1991 Medical Defense Bioscience Review (Fort DehickMD: U.S. Army Medical Research Institute of Chemical Defense, Aug. 7-8, 1991), pp. 97-100.36 H. P. Benschop et d., ‘‘Immunochemical Diagnosis and Dosirnetry of Exposure to Sulfur Mustard,” Proceedz”ngs of the 1991 MedicalDefense Biosa”ence Review (Fort Detrick MD: U.S. Army Medicat Research Institute of Chemical Defense, Aug. 7-8, 1991), pp. 67-74.37 Ibid., p. 72.38 C@ T. WUglW and T. Mark Florence, “Biomonitoring of DNA-Damaging Toxina, ” Dianne Watters et al., eds., Toxins and Targets:Effects of Natural and Synthetic Poisons on Living Cells and Fragile Ecosystems (Philadelphia PA: Hanvood Academic Publishers, 1992),p. 172.39 Ibid., p. 172.

TechnicalAspects ofBiologicalWeaponProliferation 3Biological and toxin warfare (BTW) has been termed“public health in reverse” because it involves thedeliberate use of disease and natural poisons to incapacitateor kill people. Potential BTW agents include Livingmicroorganisms such as bacteria, rickettsiae, fungi, and virusesthat cause infection resulting in incapacitation or death; andtoxins, nonliving chemicals manufactured by bacteria, fungi,plants, and animals. Microbial pathogens require an incubationperiod of 24 hours to 6 weeks between infection and theappearance of symptoms. Toxins, in contrast, do not reproducewithin the host; they act relatively quickly, causing incapacitationor death within several minutes or hours.The devastation that could be brought about by the military useof biological agents is suggested by the fact that throughouthistory, the inadvertent spread of infectious disease duringwartime has caused far more casualties than actual combat. 1 Suchagents might also be targeted against domestic animals and stapleor cash crops to deprive an enemy of food or to cause economichardship. Even though biological warfare arouses generalrepugnance, has never been conducted on a large scale, and isbanned by an international treaty, BTW agents were stockpiledduring both world wars and continue to be developed as strategicweapons— “the poor man’s atomic bomb’’—by a small butgrowing number of countries. 21 John P. Heggers, “Microbial Lnvasion-The Major Ally of War (NaturalBiological Warfare),” Military Medicine, vol. 143, No. 6, June 1978, pp. 390-394.2This study does not address the potential use of BTW agents by terrorist groups.For a discussion of this topic, see U.S. Congress, Oftlce of lkchnology Assessment,Technology Against Terrorism: The Federa/ Ej@rt, O’IX-ISC-481 (Washingto~ DC:U.S. Government Printing Office, July 1991), pp. 21-22. See also Jessica Eve Stem,“Will lkrronsts Tbrn to Poison?” Orbis, vol. 37, No. 3, summer 1993.I 71

72 | Technologies Underlying Weapons of Mass DestructionThe Biological and Toxin Weapons Conventionof 1972, signed and ratified by some 130countries, bans the development, production,stockpiling, and transfer of BTW agents forwarfare purposes. This treaty was weakened fromthe start, however, by the impossibility of banningresearch on BTW (agents, the fact that thedevelopment, production, and storage of BTWagents are permitted for defensive or peacefulpurposes, and the absence of formal mechanismsfor verification or enforcement. 3 It has also beenalleged that key signatory states such as theformer Soviet Union have systematically violatedthe treaty. According to a recent White Housereport, ‘‘the Russian offensive biological warfareprogram, inherited from the Soviet Union, violatedthe Biological Weapons Conventionthrough at least March 1992. The Soviet offensiveBW program was massive, and included production,weaponization, and stockpiling. ’The biological disarmament regime has alsocome under growing pressure from the globalspread of biotechnologies suitable for both civiland military applications, and from the revolutionin genetic engineering, which has made it possibleto manipulate the genetic characteristicsencoded in the chemical structure of the DNAmolecule. Soon after the publication in 1973 oftechniques for cutting and splicing DNA moleculesacross species lines, a few concernedscientists worried that these powerful methodsmight be applied to develop new and moredangerous biological-warfare agents. Today, somedefense planners believe that genetic engineeringand other biotechnologies may eventually removesome of the military liabilities of BTW agents,increasing the attractiveness of these weapons tostates of proliferation concern. It is not clear,however, that such techniques would significantlyalter the military utility of BW agentscompared with the numerous already knownagents.Given the perceived need to strengthen theBiological Weapons Convention (BWC), and thefact that the Chemical Weapons Convention(CWC) includes formal verification measuressuch as onsite inspections, a number of countrieshave proposed establishing a similar verificationregime for the BWC. (See box 3-A, pp. 74-75.See also ch. 2 for discussion of procedures andtechnologies that might be used to detect theproduction of chemical weapons.) Nevertheless,verifying the nonproduction of biological weaponsis inherently more difficult than for chemicalweapons, for three reasons.First, since BW agents are living microorganismsthat reproduce inside the host, they are muchmore potent per unit weight. Thus, whereas CWagents must be stockpiled in the hundreds orthousands of tons to be militarily significant, afew kilograms of a BW agent such as anthraxbacteria could cause comparable levels of casualties.Such a small quantity of agent would berelatively easy to hide.Second, whereas the production of CW agentsrequires certain distinctive precursor materials,reactions, and process equipment and leavesbehind telltale chemical signatures, the productionof BW agents involves materials and equipmentthat are almost entirely dual-use. As a result,it can be extremely difficult to distinguish illicitBW agent production from legitimate activitiespermitted under the BWC, such as the productionof vaccines.Third, because of the potency of BW agentsand the exponential rate of microbial growth, amilitarily significant quantity of BW agent couldbe produced in a matter of days in a small, easily3Some analysts worry that the Chemical Weapons Convention which was recently opened for signature and includes stringent verificationmeasures, may create incentives for some prolifemnt countries to acquire biological rather than chemical arms-both because BTW agents canbe produced in smaller, more concealable facilities, and because the Biological Weapons Convention cumently lacks effective verifkationmechanisms.4George Bus& “The President’s Report to Congress on Soviet Noncompliance With Arms Control Agreements, ” Jan. 14, 1993, p. 14.

Chapter 3-Technical Aspects of Biological Weapon Proliferation | 73concealed clandestine facility. All of these factorsmake the verification of compliance with theBWC a particularly challenging task.This chapter provides technical background onthe difficulty and detectability of BTW productionand weaponization. The discussion coversthe major technical hurdles involved in theacquisition of biological weapons and the associated‘‘signatures’ that might be monitored totrack their spread.SUMMARYAlthough biological and toxin weapons areoften grouped together with chemical weapons,they differ in important ways. The most obviousdifference is that whereas CW agents are manmade,nonliving poisons, biological agents areinfectious microorganisms that reproduce withinthe host to cause an incapacitating or fatal illness.Toxins, being poisonous chemicals manufacturedby living organisms, have characteristics of bothchemical and biological agents.Because of the ability of pathogenic microorganismsto multiply rapidly within the host, smallquantities of a biological agent—if widely disseminatedthrough the air-could inflict casualtiesover a very large area. Weight-for-weight,BTW agents are hundreds to thousands of timesmore potent than the most lethal chemicalwarfareagents, making them true weapons ofmass destruction with a potential for lethalmayhem that can exceed that of nuclear weapons.The lengthy incubation period of microbial pathogensplaces a major limitation on their battlefieldutility, except in situations of attrition warfare,sabotage attacks against command and communicationsfacilities deep behind enemy lines, orstrikes against massed troops prior to theircommitment to battle. Moreover, the delayedeffects of biological weapons would not preventtheir covert use against crops, livestock, or peopleas a means of crippling the economy and psychologicalmorale of a targeted country.Biological and toxin weapons potentially posegreater dangers than either chemical or nuclearweapons because BTW agents are so lethal on apound-for-pound basis, their production requiresa much smaller and cheaper industrial infrastructure,and the necessary technology and know-howare almost entirely dual-use and thus widelyavailable. Despite the drawbacks of biologicalagents for tactical military use (e.g., delayedaction, the dependence on meteorological conditionsfor their effectiveness, and the difficulty ofprecise targeting), they might be attractive as astrategic weapon-particularly for small, nonnuclearnations embroiled in regional conflicts orthreatened by a nuclear-weapon state.One technical hurdle to acquiring a militarilysignificant BTW capability is to ensure adequatecontainment and worker safety during productionand weapon handling. It is also technicallydifficult to deliver biological agents to a targetarea so as to cause infection in a reliable andpredictable manner. Although a supply of standardBTW agents for strategic attacks againstwide-area civilian targets (e.g., cities) would berelatively easy to disseminate using crude deliverysystems such as an agricultural sprayer, thismeans of delivery would be largely uncontrollableand subject to shifting atmospheric conditions.A more predictable-and hence moretactically useful-means of delivery against pointtargets on the battlefield would require extensiveresearch, development, and testing. In particular,the integration of BTW agents into long-rangedelivery systems such as cluster bombs posescomplex engineering hurdles-although theseproblems appear to have been solved for a fewagents by the United States and the Soviet Unionduring the 1950s and 1960s.There are no specific indicators, or “signatures,”that can differentiate unambiguously betweenthe development of offensive BTW agentsand work on defensive measures such as vaccines,since both activities require the same basicknow-how and laboratory techniques at the R&Dstage. Moreover, certain types of civilian facili-

74 | Technologies Underlying Weapons of Mass DestructionBox 3-A—The Debate Over BWC VerificationThe Biological and Toxin Weapons Convention (BWC) of 1972 bans agents and delivery systems of typesand in quantities that have no justification for prophylactic, protective or other peaceful purposes," yet the treatydoes not define permitted activities more precisely and lacks any formal mechanisms for verifying compliance. Atthe time the BWC was negotiated it was considered politically impossible to obtain international support for onsiteinspections and other intrusive verification measures. Since 1972, however, the emergence of genetic engineeringand other novel biotechnologies has led to renewed concern over the seriousness of the biological and toxinwarfare threat. Given the dual-use nature of the agents and equipment the feasibility of effective verification hasbeen widely debated.At the Second Review Conference of the BWC in 1986, the participating countries sought to build confidencein the treaty regime through an annual exchange of information on permitted activities and facilities that could bepotentially associated with biological and toxin warfare. Additional confidence-building measures were adoptedat the Third Review Conference in 1991. None of these measures are legally binding, however, and less than halfof the parties to the treaty have participated to any extent in the data exchanges. At the Third Review Conference,several countries supported the drafting of a legally binding verification protocol to supplement the BWC that, interalia, would require each Party to declare all treaty-relevant biological research and production facilities. Thedeclarations would be confirmed by routine onsite inspections, supplemented by challenge inspections ofundeclared facilities.Proponents of a verification protocol argued that while a BWC verification regime could not provide absoluteconfidence in a country’s compliance, it would serve to deter the proliferation of biological and toxin weapons by:● imposing a risk of discovery and increasing the cost and difficulty of a clandestine program;■ providing opportunities for parties to demonstrate compliance, and enhancing confidence in the compliance ofothers;■ decreasing the number of sites of proliferation concern;providing an opportunity to act on national intelligence information without public disclosure of sensitive sourcesand methods;creating a legal framework for the conduct of challenge inspections; and■ reinforcing the international legal norm against the acquisition and use of BTW agents. 1The Bush administration, however, opposed the negotiation of a formal verification protocol on three grounds:the BWC could not be verified effectively because biological production facilities are dud-useand Iack distinctive“signatures”;● a negotiated regime could not be sufficiently intrusive to detect clandestine facilities, generating false confidencethat a country was in compliance with the treaty when in fact it was not; andhighly intrusive inspections by multinational teams could expose both government and commercial facilities toforeign espionage. In particular, the loss of valuable trade secrets could weaken the competitive edge of the U.S.biotechnology and pharmaceutical industries?1 FederationofA~d~nS~e~i~s, MMkingGrwponBioiogical andToxinMbapons Verification, “pKWrOSSin Identifying Effective and Acceptable Measures fora compliance Protocol tithe Bio@icai Mkapons convention,”working paper, May 1993.2 Statemnt by Ambassador Ronald F. Lehman, 11, Head of United States Delegation, Biological and TotinWeapons ConventIon Third Review Conference, Sept 10, 1991. Note that In signing the (Xemioai WeaponsConvention (CWC), the U.S. Government has determined that the highly intrusive inspections mandated in thattreaty do not pose an unacceptable risk to proprietary information or national security. However, the Inspectionsspedfied in the CWC to verify that chemical weapons are not being prochced or stored wwid not necessarily besufflcientforthe purposes of verifying the Bioiogicai Mbapons Convention. Therefore, the factthat CWC Inspectionshave been judged worthwhile despite their potentiaiforespionage does notautomatioaliy mean that proposed BWCinspections wwid be also be seen as acceptable. For a discussion of measures by which industry can protect itselffrom the ioss of proprietary information due to Chemical Weapons Convention declarations and inspections, seeU.S. Congress, Office of T~noiogy Assessment lhe Chemka/ i4@apons ConWnfkw: Effecfs on the U.S.Chem/ca/ /ndusfry, OTA-BP-ISC-1O6 (Washington, DC: U.S. Government Printing Office, August 1993).

Chapter 3-Technical Aspects of Biological Weapon Proliferation | 75While the controversy over BWC verification has focused largely on technical issues, it is fundamentally apolitical debate over whether the burden of uncertainty associated with BWC verification would hamper moreseverely the verifier or the violator. Proponents of BWC verification argue that even imperfect monitoring measureswould create a finite probability of detection that would have a significant deterrent effect on potential proliferants.Furthermore, a verification regime based on mandatory declarations of treaty-related sites and activities woulddeter the use of known facilities for BTW production, driving any violations into Clandestine facilities and thusmaking them more difficult and costly. Verification opponents counter, however, that an ineffective verificationregime would create false confidence and hence would be worse than none at all.There is also a semantic difference over the meaning of the term “verification.” The U.S. Government usesthis word in a narrow technical sense to mean the ability to detect violations within a specified regime with a highdegree of confidence. In contrast, proponents of verification see it as the cumulative result of many sources ofinformation, only some of which would be explicitly contained in a negotiated regime. Indeed, verificationproponents admit that no negotiated inspection regime could detect clandestine facilities with a high degree ofconfidence. Instead, they argue, a formal verification regime would provide a Iegal instrument to permit inspectionsof suspicious facilities that have been detected by covert intelligence means. While many countries could bedeterred from violating the treaty by a low probability of detection, some determined proliferants would require moreintrusive measures.Despite the Bush administration’s opposition to a formal verification protocol for the BWC, it did agree to theestablishment of an Ad Hoc Group of Government Experts to identify and evaluate various monitoring approachesfrom a scientific and technical standpoint. This verification experts (VEREX) group met twice in Geneva during1992, from March 30 to April 10 and from November 23 to December 4. The focus of its activities was to preparea list of 21 potential BTW verification technologies, divided into onsite and offsite categories. The onsite measureswere exchange visits, inspections, and continuous monitoring; the offsite measures were information monitoringdeclarations, remote sensing, and inspections. Each of these verification measures was evaluated in terms of 6criteria:1.2.3.4.5.6.technical strengths and weaknesses, including the amount and quality of information provided;ability to distinguish between prohibited and nonprohibited activities;ability to resolve ambiguities about activities;technology, material, manpower, and equipment requirements;financial, legal, safety, and organizational implications; andimpact on scientific research, cooperation, industrial development, and other permitted activities, andimplications for the protection of commercial proprietary information. 3determine whether combining some measures would result in synergistic effects, a methodology wasTodeveloped for assessing measures in combination. The results indicate that the interaction of two or moremeasures may yield synergistic capabilities or limitations that are not present when the measures are evaluatedin isolation.Between the first and second VEREX meetings, the U.S. position on BWC verification softened noticeably,and the new Clinton administration initiated a thorough review of its BTW nonproliferation policy. The VEREX groupmet again on May 24- June 4, 1993 to evaluate the proposed verification measures. The group met a final timeon September 13-24,1993 to prepare and adopt by consensus a final report to be forwarded to the States Partiesto the BWC. This final report will provide the basis for a decision by a majority of the participating countries onwhether to proceed with the negotiation of a legally binding verification protocol for the BWC. If such a decisionis made in the affirmative, a Preparatory Conference could take place in late 1994 followed by a SpecialConference in early 1995.3 Conferenm on Disarmament, Flna/ Deckvatkw of the Third Rev/ew Conference of the BWC, part 11,document no. BWC/CONF.111/23, p. 17.

76 | Technologies Underlying Weapons of Mass Destructionties will inevitably have the capacity to engage inillegal military production activities. Since excessivesecrecy might be indicative of offensiveintent, however, greater opemmess and transparencywould tend to build confidence in a country’sdefensive intentions.Advances in biotechnology have made it possibleto produce militarily significant quantities ofpathogens and toxins rapidly and in small, easilyconcealable facilities, greatly complicating thetask of detecting BTW programs with nationaltechnical means of surveillance. To monitorclandestine programs, it is necessary to integratedata from many sources, with a particular emphasison human intelligence: (agents and defectors).Even though much of the equipment used toproduce BTW agents is dual-use, this is notnecessarily true of the agents themselves. Mostmicrobial agents produced for peaceful purposeshave no military utility, while those that do aremade in very few places and in small quantities.Legitimate applications of dangerous pathogensand toxins (e.g., vaccine production and the use oftoxins to treat neurological disorders and forexperimental anticancer therapy) are relativelyfew at present, and are largely confinied to sophisticatedbiomedical facilities not normally foundin developing countries (with the exception of afew vaccine production plants). Moreover, giventhe fact that the biotechnology industry is still inits infancy around the globe, the background oflegitimate activities is still relatively small.The weaponization of BTW agents entails fieldtesting of biological aerosols, munitions, anddelivery systems, as well as troop exercises,which might be detectable by satellite or othertechnical means of verification. Nevertheless,testing of microbial aerosols might be concededor carried out at night or under the cover oflegitimate dual-use activities, such as the applicationof biopesticides.Despite growing concern over the militaryimplications of genetic engineering, this technologyis unlikely to result in ‘supergerms” significantlymore lethal or controllable than existingBW agents or capable of eliminating many of theuncertainties associated with the use of microbialpathogens in warfare. At the same time, however,gene-splicing techniques might facilitate the weaponizationof microorganisms and toxins andenhance their operational effectiveness by renderingthem more stable during dissemination (e.g.,more resistant to heat, ultraviolet radiation, andshear forces) and insusceptible to standard vaccinesand antibiotics. Moreover, genetic engineeringtechniques could be used to develop andproduce more effective protective vaccines for theattacking forces.In the past, most plant and animal toxins had tobe extracted from biological materials in a costlyand labor-intensive operation, but the ability to‘‘clone’ protein toxin genes in bacteria has madeit possible to produce formerly rare toxins inkilogram quantities. For the forseeable future,however, toxin-warfare agents are unlikely toprovide dramatic military advantages over existingchemical weapons, although their greaterpotency makes it easier to transport and delivermilitarily significant quantities. While it is possiblethat bioregulators and other natural bodychemicals (or synthetic analogues thereof) mightbe developed into powerful incapacitants, thenontrivial problem of delivering such agents in amilitarily effective manner would first have to besolved.BIOLOGICAL AND TOXIN AGENTSJust because a microorganism causes a seriousdisease does not make it a potential warfare agent.Of the several hundred pathogenic microbes thatdirectly or indirectly afflict humans, only about30 have been considered as likely warfare agents. 5s Department of the Army, U.S. Army Medical Researeh and Development Command, Final Programma tic Enw”ronmental ImpactStatement: Biological D#ense Research Program, RCS DD-M (AR) 1327 (Fort Detric~ MD: USAMRDC, 1989), p. A7-2.

Chapter 3-Technical Aspects of Biological Weapon Proliferation! 77Desirable characteristics of a biological agentdeveloped for military use include:the ability to infect reliably in small doses;high virulence, or capacity to cause acuteillness resulting in incapacitation or death,without experiencing an undue loss of potencyduring production, storage, and transport;a short incubation period between infectionand the onset of symptoms;minimal contagiousness of the disease fromone individual to another, to avoid triggeringan uncontrolled epidemic that could boomerangagainst the attacker’s population; 6no widespread immunity-either natural oracquired-to the disease in the population tobe attacked;insusceptibility to common medical treatments,such as generally available antibiotics;suitability for economic production in militarilysignificant quantities from availableraw materials;ease of transport, and stability under wartimefield conditions of storage and delivery;ease of dissemination (e.g., as an aerosolcloud transmitted through the air);ability to survive environmental stressesduring dissemination (e.g., heat, light, desiccation,and shear forces) long enough toinfect; andavailability of protection against the agentfor the attacking troops, such as a vaccine,antibiotics, and/or protective clothing andrespirators. 7Figure 3-1—Toxicity of CBW AgentsEstimated lethal dose(mg/person) a- 10 3I 102CW agents[ $ 10L 10 -2 Toxin agents,0-3104~- 10-5i i ’ \104it , (--7}IBW agentsa lpaper clip weighs about 500 mgSOURCE: Office of Technology Assessment, 1993,BTW agents differ widely in infectiousness,length of incubation period, and lethality (seefigure 3-l). A variety of them, including bacteria,rickettsiae, viruses, and toxins, were weaponizedduring the U.S. offensive BTW program, whichwas terminated in 1969. Brief descriptions ofsome typical BTW agents follow.| BacteriaBacteria are single-cell organisms that are thecausative agents of anthrax, brucellosis, tularemia,plague, and numerous other diseases. Theyvary considerably in infectivity and lethality. Thebacterium that causes tularemia, for example, ishighly infectious. Inhalation of as few as 10organisms causes disease after an incubationperiod of 3 to 5 days; if not treated, tularemiaresults in deep-seated pneumonia from which 30s Some analysrs have suggested that a coun~ might deliberately develop contagious BW agents, which might be rendered insusceptibleto any drugs that could be used to combat them. Japan, for example, developed plague-a highly contagious dis~ a BW agent duringWorld War II. Wbile contagious agents are commonly dismissed as too dangerous to use, they might convey a dedsive military advantage onthe attacker if (1) he could give an antidote or vaccine to his own population, (2) the agent was designed to attack crops or livestock specificto the target country, or (3) the agent could be delivered to a distant target by a long-range delivery system such as a ballistic missile. Althoughmass vaccination of the attacker’s own population appears unlikely for logistical reasons, a ruthless aggressor-state might be willing to put itsown population at risk.7The effectiveness of defenses cannot be guaranteed, however. No vaccine is 100 percent effective, since even a strong immunity can beoverwhelmed by inhaling a heavy dose of agent.

78 | Technologies Underlying Weapons of Mass DestructionBox 3-B-Anthrax as a Biological-Warfare AgentAnthrax, a severe illness caused by the bacterium Bacillus anthracis, is considered the prototypioalbiological-warfare agent. In nature, anthrax is primarily a disease of cattle and sheep but can also infect humans.it can survive for long periods in soil in a dormant (spore) phase; after infection, it reverts to an active phase inwhich it mulitipiies rapidly in the body and secretes fatal toxins. Natural human infection can result either from skincontact with infected animals, ingestion of contaminated meat or inhalation of anthrax spores, usually fromcontaminated hides. Cases of pulmonary-and in some outbreaks gastrointestinal--anthrax are almost invariablyfatal if not treated immediately with antibiotics. Inhalation of aerosolized spores would be the primary route ofinfection if the bacteria were used deliberately as a biological-warfare agent. As extrapolated from animal studies,inhalation of about 1,000 spores or less can produce fatal pulmonary anthrax in some members of an exposedpopulation, while inhalation of about 8,000 spores-weighing about 0.08 microgram-is fatal within less than aweek to a large proportion of those exposed. lAfter inhalation into the lungs, anthrax spores travel to the lymph nodes of the chest, where they becomeactive, multiplying and releasing three proteins-edema factor, lethal factor, and protective antigen. in specificcombinations, these proteins function as potent toxins, enabling the bacteria to resist host defenses and to invadeand damage host tissues via the bloodstream, resulting in uncontrollable hemorrhaging. in this manner, anthraxbacteria travel to the intestines and other areas, where they cause severe tissue damage. Initial signs of pulmonaryanthrax infection include a high fever, labored breathing, choking cough, and vomiting; it is usually fatal within 4days. 2 Although infections may respond to immediate antibiotic therapy, it is relatively easy to developantibiotic-resistant anthrax strains.in addition to its lethality, anthrax has other characteristics that make it an effective BW agent. First thedisease is not contagious from one individual to another. As a result, anthrax would not spread far beyond theintended target or boomerang against the attacker’s troops or civilian Population, assuming they do not enter acontaminated area Second, anthrax is easy to produce. The organism and its spores can be readily produced1 Te~jmonY by Barry J. Erii~ Bioio@ai VWapons Analyst, Department of the Amy, in U.S. *nate,Committee on Governmental Affairs, Global @read of Chernkxdati B/o/o@caJ Mapons: Assessing Challengestmdl?esponsesj IOlst Congress, First Session, Feb. 9, 1989 (Washington, DC: U.S. Government Printing Offioe,1990), p. 32.z Phiiip J. Hiits, “U.S. and Russian Researchers Tie Anthrax Deaths to %viets,” N8w Yom ~mes Mar. 15,1993, p. A6.to 60 percent of victims die within 30 days. 8Brucellosis, another bacterial disease, has a lowmortality rate-about 2 percent-but an enormouscapacity to inflict casualties. Infection gives riseto fever and chills, headache, loss of appetite,mental depression, extreme fatigue, aching joints,and sweating. 9 The bacterial agent that hasreceived the most attention is anthrax, whosepulmonary form is highly lethal. (See box 3-B,)Under certain environmental conditions, anthraxbacteria will transform themselves into ruggedspores that are stable under a wide range ofconditions of temperature, pressure, and moisture.One gram of dried anthrax spores containsmore than 10 11 particles; since the lethal dose byinhalation in monkeys is between l@ and l@spores, a gram of anthrax theoretically containssome 10 million lethal doses.s TXimony byBany J, ErlicQ Biological Weapons Auilyst, Department of the Army, in U.S. Senate, Comrnitt~ on Oovernrnental Affairs,Global Spread of Chem”cal and Biological Weapons: Assessing Challenges and ReWonses, IOlst Cong., 1st sess., Feb. 9, 1989 (WashingtonDC: U.S. Government Printing Office, 1990), p. 32,9 J. H. Rothschild, Tomorrows Weapons: Chemical and Biological (New York NY: McGraw-Hill, 19W), P. 212.

Chapter 3-Technical Aspects of Biological Weapon Proliferation 179in the laboratory in almost unlimited quantities, and antibiotic-resistant strains have been developed with standardselection techniques. 3Third, when anthrax bacteria are incubated under particular conditions, they transform themselves into therugged spore form, which has along shelf-life. Although most spores can be killed by boiling for 10 minutes, theycan survive for up to 20 years or longer in soil and animal hides. 4 This spore-forming ability makes anthraxparticularity well suited for delivery by missiles or bombs. The spores are stable when suspended in air, can surviveexplosive dissemination from a bomb or shell, and-unlike most pathogens-will live for several days if directsunlight is avoided. Indeed, fieldtest data have shown that anthrax spores decay at a rate of Iess than 0.1 percentper minute, which is very slow for a microorganism. 5Nevertheless, anthrax has certain liabilities as a tactical weapon. First, at lower doses there is a wide spreadin incubation times, ranging from a few days to several weeks, suggesting that the spore germinations that resultin infection can be delayed for considerable periods. 6 This variability greatly reduces the predictability and hencethe military utility of the agent. Second, anthrax spores are so persistent that they can contaminate an area forlong periods, denying it both to defender and attacker. During World War II, for example, Britain detonatedexperimental anthrax bombs on Gruinard Island off the coast of Scotland, releasing spores that remained in thetop 6 to 8 inches of soil for more than 40 years. 7 By infecting livestock, anthrax bacteria might also create newreservoirs of disease that could result in occasional outbreaks, making it impossible to use the affected areaproductively for long periods. 8 That might be the desired intent, however, were anthrax to be used as a strategicweapon.p. 74.3 wo~d Health Organi=tion, /+ea/th @e~fs ~fchem~~/ and Bjo/ogj@/ IMgapons (Geneva: WHO, 1970),4 Donald Kaye and Ro~rt G. petersdorf, “Anthrax,” Eugene Br~nwalci et at., eds., HaffiSOn’S ~fil?C@/8S Of/nferna/ Medicine, 1 Ith ed. (New Yo~ NY: McGraw Hill, 1987), p. 557.5 Wotld Health Organization, op. dt., fOOtnOtO 3, p. 94.6 presentation ~ Matthew Meselson, Harvard University, at Smlnar on BioIo@cd VWapons in the 1990S,sponsored by the Center for Strategic and International Studies, Washington, DC, Nov. 4, 1992.7 ~ese explosive anthr~ bombs were crude and ineffi~ent in creating an aerosol cloud COmpOSOd d Smallparticles. Instead, the bombs compacted the spores into the ground. Effective BW munitions would not do this.William C. Patrick Ill, former program analysis officer, U.S. Army Medical Research Institute of Infectious Diseases,Fort Detric~ MD, personal communication, 1992.B Wofld Health Organization, op. cit., fOOtllOM 3, p. 75.| RickettsiaeRickettsiae are microorganisms that resemblebacteria in form and structure but differ in thatthey are intracellular parasites that can onlyreproduce inside animal cells. Examples of rickettsialdiseases that might be used for biologicalwarfare include typhus, Rocky Mountain spottedfever, Tsutsugamuchi disease, and Q fever. Rickettsiaehave a wide variety of natural hosts,including mammals and arthropods such as ticks,fleas, and lice. If used as BW agents, however,they would probably be disseminated directlythrough the air.| VirusesViruses are intracellular parasites that are about100 times smaller than bacteria. They can infecthumans, crops, or domestic animals. Virusesconsist of a strand of genetic material (DNA orRNA) surrounded by a protective coat thatfacilitates transmission from one cell to another.The Venezuelan equine encephalitis (VEE) viruscauses a highly infectious disease that incapacitatesbut rarely kills. In contrast, some hemorrhagicfever viruses, such as Lassa or Ebola fever,are exceedingly virulent, killing 70 out of every100 victims. The AIDS virus, despite its lethality,would not be an effective warfare agent because

80 I Technologies Underlying Weapons of Mass Destructionits mean incubation period of 10 years is too slowto give it any tactical or strategic value in warfare,and because it cannot be transmitted through theair.FungiFungi do not generally cause disease in healthyhumans, although the fungus Aspergillus, whichinfects by inhalation, can cause serious opportunisticinfections in people with a weakened immunesystem. A few other fungi, such as Coccidioidesimmitis and Histoplasma capsulatum, alsoinfect naturally by inhalation and can causesevere pulmonary infections in susceptible individuals,but they have never been considered aspotential BW agents. Fungal diseases are, however,devastating to plants and might be used todestroy staple crops and cause widespread hungerand economic hardship. Examples of plant fungalpathogens include rice blast, cereal rust, andpotato blight, which can cause crop losses of 70to 80 percent.| ToxinsA toxin is a poisonous substance made by aliving system, or a synthetic analogue of anaturally occurring poison. An enormous varietyof toxins are manufactured by bacteria, fungi,marine organisms, plants, insects, spiders, andanimals, and more than 400 have been characterizedto date. Such toxins can exert their effects bythree different routes of exposure-injection,ingestion, and inhalation-and their potencyderives from their high specificity for cellulartargets. For example, many toxins bind to specificsites in nerve membranes, disrupting the transmissionof nerve impulses and causing fatalrespiratory paralysis. Other toxins selectivelyblock cellular protein synthesis or other vitalphysiological functions.From a chemical standpoint, there are twocategories of toxins: protein toxins, which consistof long folded chains of amino acids; andnonprotein toxins, which tend to be small butcomplex molecules.PROTEIN TOXINSMost bacterial toxins, including those associatedwith cholera, tetanus, diphtheria, and botulism,are large proteins. For example, variousstrains of Staphylococcus aureus, a major bacterialpathogen, secrete protein toxins that causesevere nausea, vomiting, and diarrhea lastingfrom 1 to 2 days. The United States developed oneof these toxins, Staphylococcus enterotoxin B(SEB), as a warfare agent in the 1960s. SpraydriedSEB, when disseminated through the air inaerosol form, causes a chemical pneumonia thatis more debilitating than the toxin’s gastrointestinaleffects when ingested; it can incapacitateexposed troops within hours, with recovery in 4 to6 days. l0 Botulinal toxin, secreted by the soilbacterium Clostridium botulinum, is the mostpoisonous substance known. The fatal dose ofbotulinal toxin by injection or inhalation is about1 nanogram (billionth of a gram) per kilogram, orabout 70 nanograms for an adult male.11 The toxinis also relatively fast-acting, producing deathbetween 1 and 3 days in 80 percent of victims.The U.N. inspections of Iraq after the Gulf Warconfirmed that the microbiological research facilityat Salman Pak had done development work onbotulinum toxin as a potential warfare agent.Nevertheless, attempts to weaponize botulinaltoxin have in the past failed to prevent extensiveloss of toxicity that accompanies dispersion.Ricin, a plant toxin derived from castor beans,irreversibly blocks cellular protein synthesis andis lethal when inhaled in a dose of about 10micrograms (millionths of a gram) .12 Castor10 WiU~ C. ntrick III, fo~e:rpm~ analysis officer, U.S. Army Medical Research Institute for Infectious Diseases, Fort ~tridc+ MD,personal communicatio~ 1993.11 D. M. Gill, “Bacteri~ ‘1’bxins: A ‘Ihble of Lethal Amounts,” Microbiological Reviews, March 1982, pp. 86-94.12 G. A. B~@ “wc~ me Toxic Protein of Castor Oil Seeds,” Tom”cology, VO1. 2, 1974, p. 80.

Chapter 3-Technical Aspects of Biological Weapon Proliferation 181beans are widely cultivated as a source of castoroil, which has numerous legitimate industrialapplications. The paste remaining after the oil hasbeen pressed out contains about 5 percent ricin,which can be purified by biochemical means.During World War II, several countries studiedricin as a potential chemical-warfare agent, andthe British developed and tested an experimentalricin weapon known as the ‘‘W bomb, ” althoughit was not ultimately deployed. 13 In September1978, the Bulgarian secret police (with technicalassistance from the Soviet KGB) assassinatedGeorgi Markov, an exiled Bulgarian dissidentliving in London, by firing a tiny metal ball filledwith ricin into his thigh from a pellet-gunconcealed inside an umbrella; Markov died twodays later. 14 According to published reports, Iranhas acquired 120 tons of castor beans and isallegedly purifying ricin in pharmaceuticalplants. l5NONPROTEIN TOXINSNonprotein toxins are small organic moleculesthat often have a complex chemical structure.They include tetrodotoxin @educed by a pufferfish), saxitoxin (made by marine algae known asdinoflagellates, which are taken up and concentratedby clams and mussels), ciguatoxin andmicrocystin (synthesized by microscopic algae),palytoxin (made by a soft red Hawaiian coral),and batrachotoxin (secreted by poisonous frogsindigenous to western Colombia). Typical characteristicsof nonprotein toxins are high toxicity,the absence of antidotes, heat stability (unlikemost protein toxins), resistance to other environmentalfactors, and speed of action. Saxitoxin, forexample, produces initial symptoms within 30seconds after ingestion and can cause laboredbreathing and paralysis in as little as 12 minutes.There is no known prophylaxis or therapy, and thelethal dose in 50 percent of those exposed maybeas low as 50 micrograms, a potency 1,000 timesgreater than the chemical nerve agent VX. l6Trichothecene mycotoxins are a family ofabout 100 poisonous compounds manufacturedby certain strains of the mold Fusarium that growon wheat, millet, and barley. When ingested bypeople or livestock, these toxins kill rapidlydividing cells such as those of the bone marrow,skin, and the lining of the gastrointestinal tract;they also block certain clotting factors in theblood, causing severe bleeding after injury. Inaerosol form, about 35 milligrams of the trichothecenemycotoxin T-2 can kill a 75-kilogram man;unlike most other toxins, it is also absorbedthrough the skin. Although mycotoxins are significantlyless potent than chemical-warfare agentssuch as VX, they are relatively easy to produceand are highly stable.In 1982, the Reagan administration alleged thatthe Soviet Union and its allies were using atoxin-warfare agent in Southeast Asia known as“yellow rain” whose active ingredients weretrichothecene mycotoxins. 17 The Soviets deniedthe allegations, and the United States was unableto provide convincing public evidence to back upits charges in the face of criticism on the part of13 Stwkholm htemtio~ pe~e Research Institute, The Problem of Chemical and Biological Weapons, Vol. I: The Rise of CB Weapons(Stockholm: Almqvist & WikseU 1971), p. 123.14 Rob@ Harris and Jeremy PaxmmL A Higher Form of Killing: The Secret Story of Gas and Germ Waglare (1-mdon: Chatto & Windus,1982), pp. 197-198; David Wise, ‘‘Was Oswald a Spy, and Other Cold War Mysteries,” New York Times Magazine, Dec. 6, 1992, p, 44.15 Douglas Wailer, “Sneaking in the Scuds, ” Newsweek, June 22, 1992, p. 42.16 Erlic~ op. cit., footnote 8, p. 32, See also B.J. Benton and F.C.T. Chang, ‘‘Reversal of Saxitoxin-Induced Ctiio-Resptitov F~~e byBurro XgG Antibody and Oxygen Therapy,’ Proceedings of the 1991 Medical De$ense Bioscience Review (Fort lletric~ MD: U.S. ArmyMedical Research Institute of Chemical Defense, Aug. 7-8, 1991), p. 176.17 U.S. Department of State, Chem”cal Wag2are in Southeast Asia and Afghanistan, Special Report No. 98, w. 22, 1982, P. 30.

82 | Technologies Underlying Weapons of Mass Destructionmany in the U.S. scientific community. 18 Followingearly reports of the presence of trichothecenesin samples from alleged attacks, the U.S. Armyand the U.K. Ministry of Defense initiated largeanalytical studies but were unable to confirm theearly findings. 19 Nonetheless, U.S. intelligenceofficials, based on all the: information available tothe U.S. intelligence community, remain confidentin the yellow rain allegations and have notretracted them.Compared to microbial pathogens, toxins offerthe following tactical advantages:The most toxic toxins (e.g., botulinal toxin)are exceedingly potent, so that small, easilytransportable quantities would be militarilysignificant for certain missions.Toxins tend to deteriorate rapidly oncereleased into the environment, whereas anthraxspores and persistent chemical agentscan centaminate soil for months or years. Forthis reason, territory attacked with toxinagents could be occupied more rapidly byattacking forces.Toxins are well suited to covert warfare.Whereas chemical agents leave telltale degradationbyproducts that persist for longperiods in the environment, some toxinagents break down completely over a periodof weeks or months, leaving no traces.Moreover, even fresh samples of toxin mightnot provide conclusive evidence of militaryuse if the agent occurred naturally in theregion where it was employed.Despite these operational advantages, however,toxins have drawbacks for battlefield use:Protein toxins such as botulinal toxin decomposerapidly on exposure to sunlight, air, andheat, and thus would have to be used at night.Protein toxins may be inactivated by themechanical shear forces caused by passagethrough an aerosol sprayer. 20 While lowmolecular-weighttoxins such as saxitoxinand trichothecene mycotoxins are more stablethan protein toxins, they are less stablethan chemical-warfare agents.Most toxins (with the exception of trichothecenemycotoxin T-2) do not penetrate theskin, nor would toxin lying on the groundcreate a vapor hazard. 21 Weaponization thereforerequires the creation of a small-particleaerosol cloud, in which the toxin mustremain airborne to be effective.The inhalation threat posed by protein toxinssuch as botulinal toxin can be counteredeffectively with modern gas masks (althougha surprise or covert attack might exposepersonnel to lethal concentrations beforethey could don their masks).For conventional battlefield use, toxins offerfew military advantages over chemical nerveagents. Toxins would, however, probably besuperior for small-scale clandestine operations.ACQUIRING A BTW CAPABILITYThe acquisition of a militarily significant BTWcapability would probably involve the followingsteps (see figure 3-2):la Jfi~RobinsoG Je~e Guille~ and Matthew Meselso~ “Yellow Rain in Southeast Asia: ‘he StOry COlkipSeS,” SUS~ wrigh~ cd.,Preventing a Biological Arms Race (Cambridge, MA: MIT Press, 1990), pp. 220-238. See also U.S. Senate, Cornrnittee on Foreign Relations,Subcommittee on Arms Control, Oceans, International Operations, and Environment, 98th Cong., 1st sess., YelZ~w Rain: The Arms ConrrolImplications, Feb. 24, 1983 (Washington DC: U.S. Government Printing Off@ 1983).19 Robinson et al., op. cit., footnote 18, pp. **8-**9.20A fw prote~ tox~ we quite s~ble: SEB ~ ~~ for e~ple, is not &s~oy~ ~t~ boiling for 30 minutes. III additio~ the stibilityof protein toxins can be increased through a technique known as microeneapsulation (see production section below), David S. Huxsoll, formerdirector, U.S. Army Medical Research Institute for Infectious Diseases, personal comrnunicatiom 1992.21 Shirley Freeman, ‘‘Disease as a Weapon of War, ” Pacific Research, vol. 3, February 1990, p. 5.

IChapter 3-Technical Aspects of Biological Weapon Proliferation | 83Figure 3-2—Biological Weapon AcquisitionR&Dv’or novel agent– —v— – --~ Mampulate genehc ~characteristicsI(optional)Produce agent, Test suitability EMicro-A , >’ ;;;>~~~;~>E-->F for weapon> encapsulate ->?agentIIDesign, test, and build munitionsI Area delwery: I vI sprayer system I I ~ ~ ‘-~L.––—.:–-–L— - )Field- ‘ MaSSiFill‘ >~—.--.—test produce munitionsIPoint dellvery: ‘cluster bomb or warhead ,~— —- . -–. J1 filledLm!!!’ti!!sAcquire delivery systemr?=flr%%=”!E!!Z2EE!IDevelop strategic andLJtactical BW battle plansEiiiiaadelivery systemAcquire operational capability I>~Integrateweapon systemsinto military ,forcesdmOperational> capabilitySOURCE: Office of Technology Assessment, 1993.1. Establishment of one or more facilities and 3.associated personnel with organizationaland physical provisions for the conduct ofwork in secret; 4.2. Research on microbial pathogens and toxins,including the isolation or procurementof virulent or drug-resistant strains;Pilot production of small quantities of agentin flasks or small fermenter systems;Characterization and military assessment ofthe agent, including its stability, infectivity,course of infection, dosage, and the feasibilityof aerosol dissemination;

84 | Technologies Underlying Weapons of Mass Destruction5.6.7.8.Research, design, development, and testingof munitions and/or other disseminationequipment;Scaled-up production of agent (possibly inseveral stages) and freeze-drying;Stabilization of agent (e.g., through microencapsulation)and loading into spray tanks,munitions, or other delivery systems; andStockpiling of filled or unfilled munitionsand delivery vehicles, possibly accompaniedby troop training, exercises, and doctrinaldevelopment. (In some but not allcases, a country planning the offensive useof BTW agents would take measures toprotect its own troops, such as immunization,the acquisition of respirators, andtraining in self-protective measures.)The key steps in this acquisition sequence areexamined below in terms of their technicaldifficulty.| Research, Development, andWeaponizationCountries seeking a BTW capability are likelyto start with the development of standard agentsthat have been weaponized in the past, such asanthrax, tularemia, and botulinum toxin. Nearlyall proliferant states lack the sophisticated scientificand technological infrastructure needed todevelop novel agents such as exotic viruses,whose military characteristics are poorly understood.BTW agents are widely accessible. Pathogenicmicroorganisms are indigenous to many countriesand can be cultured from infected wild animals(e.g., plague in rodents), living domestic animalsor infected remains (e.g., Q fever in sheep,anthrax in cattle), soil in endemic areas (whichmay contain trace amounts of anthrax bacteriaand other pathogens), and spoiled food. Certainbiological supply houses also ship strains ofmicrobial pathogens to scientists throughout theworld. For example, American Type CultureCollection (ATCC), a nonprofit company inRockville, MD, acts as a clearinghouse forresearch institutions around the world, shippingeach year approximately 130,000 cultures ofweakened (’‘attenuated”) pathogens to 60 nations.22 While such attenuated strains are notvirulent and hence could not be converted directlyinto biological weapons, they would be useful forBTW research and development and for preparingself-protective vaccines. Methods for culturingorganisms and for inducing spore formation arealso described in the open scientific literature, andstandard microbiological procedures can be usedto produce more virulent or antibiotic-resistantstrains of microbial pathogens.Once a proliferant had acquired BTW agents,they might be modified genetically throughsimple selection techniques to increase theirvirulence or effectiveness. For example, incubatingmicrobial pathogens in the presence ofstandard antibiotics can induce the emergence ofdrug-resistant strains, which can then be subcultureand mass-produced. Agent developmentwould also involve “weaponization," or a thoroughassessment of the agent military potential,including its stability, infectivity, course of infection,and effective dosage. This step wouldinclude the testing of candidate agents to determinetheir effectiveness, including the feasibilityand reliability of aerosol dissemination. Suchtests might be carried out either in a sealed aerosolchamber or in field studies of simulant microorganismsat a remote testing range.THE DUAL-USE DILEMMAA fundamental problem in countering theproliferation of biological and toxin weapons isthe fact that much of the necessary know-how andtechnology is dual-use, with legitimate applicationsin the commercial fermentation and biotechnologyindustries. Many developing countriesn Wc N~Im d RoM WiIIdreW, “&adly Contagio~” The New Republic, vol. 204, No. 5, Feb. 4, 1991, p. 18.

Chapter 3-Technical Aspects of Biological Weapon Proliferation | 85have acquired industrial microbiology plants forthe production of fermented beverages, vaccines,antibiotics, ethanol (from corn or sugar cane),enzymes, yeast, vitamins, food colors and flavorings,amino acids, and single-cell protein as asupplement for animal feeds. 23 This global expansionof the civilian biotechnology industry, combinedwith the growing number of molecularbiotechnologists trained in the West, has createdmuch broader access to the expertise and equipmentneeded for the development of BTW agents.Sophisticated laboratories that might be used forthe design of novel BW agents are inexpensivecompared with nuclear weapon plants. Moreover,biotechnology is information-intensive ratherthan capital-intensive, and much of the relevantdata are available in the published scientificliterature. For these reasons, it is virtuallyimpossible for industrialized states to preventthe diffusion of weapon-relevant informationto states of proliferation concern.It has been estimated that more than 100countries have the capability-if not necessarilythe intent-to develop at least crude biologicalweapons based on standard microbial and toxinagents. 24 In addition to the United States, Russia,Western Europe, and Japan, countries with anadvanced commercial biotechnology infrastructureinclude Argentina, Brazil, Chile, Cuba, India,Israel, the People’s Republic of China, Taiwan,and Thailand. Cuba, in particular, has an advancedbiotechnology industry that exports vaccinesand reagents to other Latin Americancountries .25 While Iraq lags somewhat behind thisgroup of countries, Baghdad established a nationalCenter for Genetic Engineering and Biotechnologyin the late 1980s, initially staffed withonly four scientists. 26 As an increasing number ofdeveloping countries become involved in commercialbiotechnology, they may be tempted toexplore its military potential.In addition, the legitimate use of toxins formedical therapy and biomedical research is increasinglywidespread. Botulinal toxin, for example,is used to treat abnormal muscle spasmsknown as dystonias by selectively paralyzing thespastic muscles; it has also been applied cosmeticallyto smooth wrinkles. 27 Toxins such as ricin,when linked to antibodies that selectively targetcancer cells, have shown promise in clinical trialsas an anticancer therapy. 28 Furthermore, saxitoxinand other exotic toxins that bind specifically tochannels or receptors in nerve-cell membranes arevaluable research tools in neuroscience. Theinherently dual-use nature of many pathogens andtoxins makes the prevention of BTW-relevantresearch extremely difficult. Consumption oftoxins for medical therapy and research hasalready expanded to the current level of hundredsof grams per year, and the anticipated furthergrowth of such therapies will eventually blur the23 For an overview, see U.S. Congr=s, OffIce of ‘lkchnology Assessment, Biotechnology in a Global Economy, OTA-BA-494 (w~mto~DC: U.S. Government Printing Office, October 1991).u ~s~ony of moms Welcb D~~ty Assistant Smre- of Defense (~emic~ Matters), reported in D#ense Week, May 9, 1988.2S ~wond A. Zilinska% “Biological Warfare and the Third World” Politics and the L~e Sciences, vol. 9, No. 1, August 1990, p. 61.26 presentation by Raymond Zilinskas, Washington Sh’ategy s~, Washington, DC, July 14, 1992.27 Tom Waters, ‘me F~e M of M.alcing Poisou” Discover, vol. 13, No. 8, August 1992, p. 32; and Anna Evangeli, ‘ ‘Botulism Gives Fac~New base of Life, ” New Scien~ist, vol. 137, No. 1859, Feb. 6, 1993, p. 18. See also Fritz P. Gluckstein and Mark Hallet, Clinical Use ofBotulinum Toxin: January 1987 through September 1990, 318 Citations (Washington DC: National Library of Medicine/U.S. GovernmentPrinting Office, 1990).28 David Fitzgerald and Isa Pastaq ‘‘Targeted Toxin Therapy for the Treatment Of Cancer, ” Journal of the National Cancer Institute, vol.81, No. 19, October 1989, pp. 1455-1463; Andrew A. Hertler and Arthur E. Frankel, “Imrnunotoxins: A Clinical Review of Their Use in theTreatment of Malignancies,” Journal of Clinical Oncology, vol. 7, No. 12, December 1989, pp. 1932-1942; Lee H. Pai and Ira PastarL‘‘Immunotoxin Therapy for Cancer,’ Journal of the Amen’can Medical Association, vol. 269, No. 1, Jan. 6, 1993, pp. 78-81.

86 I Technologies Underlying Weapons of Mass Destructiondistinction between medically useful and militarilysignificant quantities of toxins. 29 The legitimateapplications of toxins will therefore have toremain relatively open to preclude their use forillicit purposes.Finally, the development of defenses againstBTW attack-an activity explicitly permitted bythe Biological Weapons Convention-draws onmuch of the same knowledge base needed todevelop offensive BTW agents. Indeed, “threatassessment, an important aspect of some biological-defenseprograms, includes the evaluationof defenses under simulated warfare conditionsand may be indistinguishable from the developmentof offensive BTW agents .30 Furthermore,certain defensive activities may have offensiveapplications. According to one assessment, ‘‘thevirulence of micro-organisms is studied both forits relevance to the field of natural infections andin order to produce living, attenuated vaccines.Such knowledge can obviously be used more orless directly to make a BW agent more virulent.”31 For these reasons, biological-defenseactivities such as the development of vaccinesmay arouse concerns about offensive intentionsunless they are conducted openly and in anunclassified environment..In sum, research on potential BTW agents doesnot necessarily imply an offensive weapon programbecause much of the relevant knowledge ismultiuse. This inherent ambiguity means that atthe R&D stage, the only difference betweenoffensive and defensive activities is one of intent.The policy dilemma is that progress in controllinginfectious diseases requires the free and openflow of information, so that researchers can buildon and validate the work of others; imposingcontrols on the publication of results with potentialmilitary implications would seriously impedelegitimate scientific research worldwide. Nevertheless,openness may impose some limits on themisuse of biomedical research for maliciouspurposes.| Large-Scale ProductionBTW agents would be relatively easy andinexpensive to produce for any nation that has amodestly sophisticated pharmaceutical or fermentationindustry. Indeed, mass-productionmethods for growing pure cultures are widelyused in the commercial production of yogurt,yeast, beer, antibiotics, and vaccines. Nearly allthe equipment needed for the production ofpathogens and toxins is dual-use and widelyavailable on the international market, increasingthe potential for concealing illicit activities underthe cover of legitimate production. Whereas atypical vaccine production facility costs a minimumof $50 million, a much less elaborateindustrial fermentation plant suitable for conversionto BTW agent production could be built forabout $10 million. 32 In such a‘ ‘no-frills’ facility,bacteria could be grown in standard dairy tanks,brewery fermenters, or even in the fiberglasstanks used by gas stations.In contrast to chemical-warfare (CW) agents,no specialized starting materials are required forthe production of biological and toxin agentsexcept for a small seed stock of a diseaseproducingorganism. Nutrients such as fermentationmedium, glucose, phosphates, peptone, anda protein source (e.g., casein, electrodialyzedwhey, or beef bouillon) are widely available andare routinely imported by developing countriesthat have commercial fermentation industries. Astate seeking a CW capability, in contrast, re-29& p. ~licoff, Senior Me~~, ‘lMmical Staff, Sandia National Laboratories, personal COmlll@catiolL 1992.30 s= su~m Wn@t ~d SW: Kc@@ ‘‘~ probl~ of ~terpre@ tie U.S. BiOIOgic~ D~e~ llese~ch program,’ SUSan Wrigh~cd., Preventing a Biological Arms Race (Cambridge, MA: MIT Press, 1990), pp. 167-196.31 stw~o~ htemtio~ Pea:e Re~~h lnsti~te (SIPIU), The Problem of Chemical and Biological Wa~are, Vol. VI: Technical Aspectsof Early Warning and Verification (Stockholm: Almqvist & Wiksell, 1975), p. 24.32 ~temiew tit.b Dr. Ron l“hibeauto~ Wyeth-Ayerst vaccine production pkm~ Marietta, pA, &t. 22, 1992.

Chapter 3-Technical Aspects of Biological Weapon Proliferation | 87Figure 3-3-Production of Biological Agents by Fermentation,~’y /’~Freeze-driedseed culture flT‘\Production-scalefermenterPropagation vessels~LY@l.“3 .c--—‘7 .—. .C2./’”Final processing—>SOURCE: U.S. Senate, Committee on Governmental Affairs, Global Spread of Chemical and Biological k$bapons,IOlst Cong., 1st sess., Feb. 9, 1989 (S. Hrg. 101-794), p. 241.quires hundreds or thousands of tons of unusualprecursor chemicals that may be difficult toobtain.PRODUCTION OF BACTERIAL AGENTSA biological-warfare plant would contain fermentersand the means to sterilize and dispose ofhazardous biological wastes on a large scale. Asmall vial of freeze-dried seed culture, grown ina fermenter in a nutrient medium kept at constanttemperature, can result in kilograms of product(e.g., anthrax bacteria) in as little as 96 hours. 33(See figure 3-3.) Microbial pathogens such asplague bacteria can also be cultivated in livinganimals, ranging from rats to horses.Fermentation can be carried out on a batchbasis or in a continuous culture from whichorganisms are constantly removed and an equalvolume of new culture medium is added. Anadvantage of continuous culture is shorter turna-33 Er~c~ op. cit., foomote 8, P. 32.

88 | Technologies Underlying Weapons of Mass Destructionround time, increasing the productivity of eachfermenter. Indeed, if nutrients are supplied continuouslyand natural growth-inhibitors are removedas soon as they are formed, the bacterialculture can be maintained indefinitely in a phasein which it multiples exponentially. A continuousculture can therefore yield nearly 10 times asmuch product per volume of culture medium asthe batch approach. 34 Nevertheless, batch culturehas generally been used to cultivate BW agents inthe past because continuous culture is technicallymore complex and sometimes results in a loss ofpotency. High levels of purity are not required forBW agents; 60 to 70 percent purity will sufficeand is easy to obtain. The main technical hurdlesin bacterial production are:the danger of infecting production workers;genetic mutations that may lead to a loss ofagent potency; andthe contamination of bacterial cultures withother microbes (e.g., bacterial viruses) thatmay kill them or interfere with their effects.Although biological agents can be grown inordinary laboratory flasks, an efficient productioncapability would require the use of specializedfermenters. Until fairly recently, large-scale productionof bacteria for commercial or militarypurposes required tank-type bioreactors containingthousands of liters of culture, with mechanicalstirring or a flow of air to oxygenate the culturemedium. During World War II, for example, theJapanese Army ran a top-secret BTW facility inoccupied Manchuria at which more than 3,000workers grew kilogram quantities of pathogenicbacteria (including the agents of anthrax, brucellosis,plague, and typhus) in giant vats. 35Also during World War II, the United Statesand Britain planned to produce anthrax bacteria inlarge quantities for use in a strategic bombingcampaign against Germany. In 1943, a pilotanthrax production plant became operational atCamp Detrick, MD, staffed with about 500bacteriologists, lab assistants, chemical engineers,and skilled technicians. 36 Based on thisexperience, the decision was made to build afill-scale plant at Vigo, Indiana, at a cost of $8million, where 1,000 workers would manufacturemore than 500,000 anthrax bombs a month (or,alternatively, 250,000 bombs filled with botulinaltoxin). Since both agents store well, they could bestockpiled in large quantities. The Vigo plant wascompleted in early 1945 but never actually wentinto production. 37 Although it is far from certainthe anthrax bombs would have worked as designed,it is possible that large areas of Germanycould have been rendered uninhabitable for decades.In 1950, the U.S. Congress voted $90 millionto build another BTW plant called X-201 at arenovated arsenal near Pine Bluff, Arkansas. Thenew production facility had 10 stories, 3 of themunderground, and was equipped with 10 fermentersfor the mass-production of bacterial pathogenson short notice. 38 To give some idea of thescale involved, the Pine Bluff facility and itsassociated munitions-falling plant required a watersupply of 2 million gallons per day, an electricalpower supply of 5 megawatts, and an initialworkforce of 858 people. 39 Production of BW~ SIPM, VO1. VI, op. cit., footnote 31, p. 43.N me Jap~~B~ fmfi~ WaS c~e.~~ Unit 731. John W. Powe~ “A Hidden Chapter in History,” Bulletin ojtheAro?nic ~denti$t$,vol. 37, No. 8, October 1981, pp. 44-52. For a more detailed deseriptio~ see Petes Williams and David Wallace, Unit 731: Japan’s SecretBiological Warjare in World War II (New Yorlq NY: Free Press, 1989).3 6 = ~d p~, op. cit., footnote 14, pp. 1(X L101.37 Ibid,, p. 103.SE Ibid., p. 160.39 ~~ew Me~lsO~ hlartin M. Kapl~ and Mark A. Mokukk-y, ‘ ‘Vcrifkat.ionof BiologieaJ and ‘Rm.in WMpOrM Di saxmarnen4° Science& Global Security, vol. 2, Nos. 2-3, 1991, p. 237.

Chapter 3–Technical Aspects of Biological Weapon Proliferation | 89agents on such a vast scale is far in excess of whata country would need to wreak enormous destructionon an adversary.Over the past decade, technological advancesassociated with the commercial biotechnologyindustry have made it possible toproduce large quantities of microorganisms inmuch smaller facilities. The introduction ofcomputer-controlled, continuous-flow fermentersand compact ultrafiltration methods has vastlyincreased productivity, making it possible toreduce the size of a fermenter to about 1,000-foldless than conventional batch fermenters that giveequivalent production. 40 Real-time sensors andfeedback loops under microprocessor controlhave also optimized culture conditions, resultingin much higher yields and better quality productsthan in the past. The resulting increase in productivityhas made it possible to reduce the amountof trained manpower needed to operate largescalefermenters and to use smaller, more concealableproduction equipment. Of course, adeveloping country could produce many smallscalebatches of BTW agents in laboratoryglassware without the need for high-technologyfermenters.PRODUCTION OF VIRAL AND RICKETTSIALAGENTSPathogenic viruses and rickettsiae are intracellularparasites that can only reproduce insideliving cells. There are two approaches to cultivatingthese agents: in intact living tissue (e.g., chickembryos or mouse brains) or in isolated cellsgrowing in tissue culture. The latter approach istechnically simpler because it requires only flasksand nutrient medium, but certain viruses (e.g.,influenza) do not grow well in tissue culture andmust be cultivated in fertilized eggs. In 1962, FortDetrick used more than 800,000 eggs for thecultivation of pathogenic viruses. 41Growing viruses and rickettsiae in culturedmammalian cells offers greater control but involvescertain technical hurdles. The cells mustadhere to a surface to grow and also require acomplex culture medium based on blood serumobtained from horses and cows. Until recently,cultured mammalian cells were grown on theinner surface of rotating glass bottles, whichlimited the volume of production. Over the pastdecade, however, new methods for cultivatingmammalian cells have been developed that permithigher concentrations of cells and greater recoveryof product. For example, allowing the cells togrow on surface of beads suspended in culturemedium has permitted the scaling-up of production.Yield has been improved further by replacingthe beads with microcarriers, which have aporous internal structure into which animal cellscan grow. 42Hollow-fiber technology offers an even moreefficient method of growing anchoragedependentmammalian cells in high concentrationsfor the cultivation of viruses or rickettsiae.The cells are grown on the outer surface of thinfibers that are immersed in the growth medium;air is pumped through the fibers and diffusesthrough the fiber wall to reach the cells. 43 Sincea single hollow-fiber bioreactor is equivalent toseveral thousand one-liter roller bottles, it occu-~ Gove~ent of Aus~~ia, ‘Impact of Recent Advances in Science and ‘Ikdmology on the Biological Weapons Convention’ BackgroundDocument on New Scientific and Technological Developments Relevant to the Convention on the Prohibition of the Development, Productionand Stockpiling ofBacten’ological (Biological) and Tom’n Weapons and on Their Destruction, Third Review Conference of the BWC (Genev%Switzerland), Document No. BWC/CONF.111/4, Aug. 26, 1991, p. 3.41 SePOW M. Her~~ Chemical ~nd Biological Wa$are: Am~ca’~ Hidden Arsenal @I&uMpofis, IN: Bobbs-M@l, 1%8), p. 78.42 S.B. Wose, Molecular Biotechnology, 2d ed. (Oxford, England: Blackwell Scientitlc Publications, 1991), P. 116.43 Government of the U.S.S.R, “Selected Scientilc and Technological Developments of Relevance to the BW Conventio~” BackgroundDocument on New Scientific and Technological Developments Relevant to the Convention on the Prohibition of the Development, Productionand Stockpiling of Bacteriological (Biological) and Tom”n Weapons and on Their Destruction, Third Review Conference of the BWC, Genev~Switzerland, Document No. BWC/CONF.111/4/Add.1, Sept. 10, 1991, p. Al 1.

90 | Technologies Underlying Weapons of Mass Destructionpies less than one-twentieth the volume of theprevious technology. 44 Advantages include economyand the high concentration and purity of theend-product, which reaches 98 percent on leavingthe reactor. In sum, the new cell-culture techniquesgreatly simplify the production of virusesand rickettsiae and allow large-scaleyields from very small facilities.PRODUCTION OF TOXINSThe most efficient way to produce bacterialtoxins is through fermentation. Botulinal toxin,for example, is derived from a culture of Clostridiumbotulinum bacteria, which multiply rapidlyunder the right conditions of temperature, acidity,and the absence of oxygen. It takes only about 3days to grow up a dense culture of the bacterialcells, which extrude botulinal toxin into thesurrounding culture medium. (Purification of thetoxin is neither necessary nor desirable, since ittends to reduce stability.) During World War II,Japan’s Unit 731 produced kilogram quantities ofbotulinal toxin in a fermenter approximately 10feet high and 5 feet wide. 45 A crude preparation oftoxin can be freeze-dried down to a solid cake,which is then milled into a fine powder suitablefor dissemination through the air. The millingoperation is exceedingly hazardous, however, andmust be carried out under high-containmentconditions. Plant toxins such as ricin, whose rawmaterial is widely available, could easily beproduced in the hundreds of kilograms.With recombinant-DNA techniques, rareanimal toxins—formerly available only in milligramamounts-can be prepared in significantquantities in microorganisms. Althoughthese techniques are still largely restricted to theadvanced industrial countries, they are spreadingrapidly around the world. One method, known asthe “cloning” of toxin genes, involves identifyingDNA sequences in plants and animals thatgovern the production of protein toxins, transferringthese genes to a suitable microbial host, andmass-producing the toxin in a fermenter. In thisway, ordinary bacterial cells can be transformedinto miniature toxin factories. % Production ofanimal toxins in bacteria involves certain technicalhurdles, however. Bacteria typically produceand secrete toxins only under special conditions,which may not be met in an artificial environment;and bacteria may be unable to performcertain biochemical “processing” steps neededto convert a protein toxin to its active form. 47 Forthese reasons, it maybe necessary to clone plantand animal toxins in yeast or mammalian cells, atechnically more challenging task.Nonprotein toxins are considerably harderthan protein toxins to produce in militarilysignificant quantities. Until recently, even smallamounts of nonprotein toxins such as saxitoxinhad to be extracted from large quantities ofbiological material with costly and laborintensivepurification methods. For example, 270kilograms of toxin-containing clam siphons yieldedless than 5 grams of saxitoxin. 48 Although somenonprotein toxins such as saxitoxin and tetrodotoxincan be synthesized in the test tube withmultistep procedures, the overall yield is only44 @vement of the United States, “lkchnological Developments of Relevance to the Biological and ‘Ibxin Weapons Convention”BackgroundDocument on New Sciennj?c and Techno[ogica[Developments Relevant to the Convention on the Prohibition of the Development,Production and Stockpiling of Bacteriological (Biological) and Toxin Weapons and on Their Destruction, Third Review Conference of theBWC (Genev& Switzerland), Document No, BWC/COITF.111/4, Aug. 26, 1991, p. 30.45 Wflh ~d JVmce, op. cit., fmtnote 35, p. 124.46 Akm Wiseman, “The Organization of Production of Genetically-Engineered Proteins in Yeast,” Endeavor (new series), vol. 16, No. 4,1992, pp. 190-193,4T Mc~d Novick ~d Seth S,h- “New FOMM of Biological Warfare?’ Susan Wrigh4 cd., Preventing A Biological Arms Race(Cambridge, MA: MIT Press, 1990), p. 115.48 Edwmd J. SChantZ et al., ‘‘Paralytic Shellfish Poison. IV. A Procedure for the Isolation and PurMcation of Poison from Toxic Clam andMussel Tissues,” Journal of the American Chemical Society, vol. 79, Oct. 5, 1957, pp. 5230-5235,

..— ———Chapter 3–Technical Aspects of Biological Weapon Proliferation I 91Table 3-l—Key Production Techniques for BTW AgentsType of agent Low-tech production High-tech productionBacteria Batch fermentation, production in Genetically engineered strains, conanimalstinuous-flow fermentationRickettsiae and viruses Cultivation in eggs, mouse brains, Culture in mammalian cells grownor tissue culture (roller bottles) on beads, microcarriers, or hollowfibersProtein toxins Batch fermentation and purification Cloning of toxin gene in microbialof a bacterial toxin, or extraction of host, extractiontoxin from a plant or animal sourceNonprotein toxins Extraction from plant or animal Cloning of a series of genes, eachsourcegoverning production of one of theenzymes needed to complete astep In the biosynthetic pathwaySOURCE: Office of Technology Assessment, 1993.about 0.1 percent, making it unlikely that militarilysignificant quantities of toxin could be producedby chemical synthesis. 49 Biotechnologicalapproaches are possible but technically challenging,involving the synthesis not of a single proteinbut of an entire series of enzymes, each necessaryto catalyze one step in a complex series ofreactions .50Production techniques for the various types ofBTW agents are summarized in table 3-1. Withadvanced fermentation techniques availabletoday, a militarily significant supply of BTWagents could be produced over a period ofseveral days, obviating the need for the longtermstockpiling of agents. As a result, a BTWproduction facility might remain largely quiescentin peacetime. After completing R&D,weaponization, and pilot-production tests onBTW agents, a proliferant could build productionand storage facilities and either keep them mothballedor in use for legitimate commercial purposes.Clandestine production facilities might bekept in reserve, ready to be diverted to the rapidmanufacture of BTW agents in the event a majorconflict breaks out. Alternatively, a commercialproduction facility could be kept in operation andconverted to BTW production in wartime. Theadvantage of the latter option is that it would beeasier to retain the necessary trained staff andup-to-date equipment, albeit at some cost insecrecy.CONTAINMENT MEASURESSince working with pathogenic microorganismsis extremely hazardous, specialized physicalcontainmentor ‘‘barrier’ measures are needed toprotect plant workers and the surrounding populationfrom infection. Great care must be taken toprevent BTW agents from escaping from aproduction facility and causing a devastatingplague in the country producing the weapons.In advanced industrial countries, work onhighly infectious microbial agents is carried outin high-centainment (Biosafety Level 3 or 4)facilities. In a BL3 facility, all personnel havebeen immunized against the infectious agentsthey work with. Since no vaccine is 100 percenteffective, however, they also wear protective@ Muel L. Sanches et al., Chemical Weapons Convention (CWC) Signatures Analysis (Ml figto% VA: System plm g Corp, FinalTechnical Report No. 1396, August 1991), p. 89.so ~05e, op. cit., footnote 42, p. 84.

92 | Technologies Underlying Weapons of Mass Destructionclothing, goggles, and face masks. Microorganismsare manipulated in special biohazard safetycabinets maintained under “negative’ pressure(lower than the outside atmosphere), so that airflows into the work area. In addition to theseprimary barriers, secondary barriers to the spreadof infectious materials include the use of highefficiencyparticulate air filters and the incinerationof exhaust. 51 Because viral particles areabout a hundredth the size of bacteria, they aremore difficult to contain with filters and othermeans. Moreover, spore-forming bacteria (e.g.,the agents of anthrax and tetanus) foul theair-handling system with long-lived spores, whichcan easily contaminate other products. As a result,these bacteria are normally produced in separatefacilities. 52A BL4 facility, the highest level of containment,is designed to isolate the human operatorfrom the infectious agents. Since research ondangerous microbial pathogens requires handlingmuch lesser quantities of” hazardous material thandoes production, it is generally performed insmall BL4 enclosures inside a less stringent BL3facility .53 Such enclosures generally consist ofsealed boxes with rubber-glove ports that provideabsolute containment, and ‘hoodlines’ that makeit possible to move hazardous cultures directlyfrom a glove-box to an autoclave, which destroysthe infectious microorganisms with superheatedsteam. In a larger BL4 research or productionfacility, the human workers are isolated from themicrobes, rather than vice-versa. Each operatorwears a self-contained “space suit” and iscompletely isolated from the surrounding room,which is contaminated with infectious agents. Heor she enters the laboratory through an air-lockand hooks up to a supply of compressed air. Thesuit is kept under positive pressure so that if thereis any loss of physical integrity, the leaking airwill blow outwards, reducing the risk of infection.A developing country seeking to developbiological weapons would probably use muchless elaborate containment measures. DuringWorld War II, for example, the Japanese Army’sUnit 731 produced vast quantities of highlyinfectious agents, yet the workers were protectedonly by wearing rubberized suits, masks, surgicalgloves, and rubber boots, and by receivingvaccinations against the agents they were workingwith. The United Nations inspections of Iraqafter the 1991 Gulf War revealed that BTWresearchers in that country’s BTW program usedsurprisingly rudimentary containment measures,at the level of a BL2 facility. Laboratory technicianswere vaccinated against the infectiousagents they worked with and used simple laboratoryhoods, but they did not wear masks orprotective clothing.Commercially available containment systemsused for vaccine production might be suitable forcultivating highly pathogenic organisms. To complywith environmental and occupational-healthstandards and to ensure the purity of products forhuman use, many pharmaceutical plants carry outthe microbial production of antibiotics and otherdrugs in a “clean room” that is comparable to aformally designated BL4 facility. Clean rooms fordrug production are normally kept Under positivepressure to keep contaminants out, whereas areasof a vaccine plant used for the culture of infectious microorganisms are kept under negativepressure to prevent the dangerous microbes fromescaping. In principle, the direction of air flowcould be reversed, albeit with some difficulty.Methods for sterilizing equipment after usewith hazardous microorganisms include physicalmeasures such as dry heat or pressurized, superheatedsteam; ionizing radiation such as x-rays‘1 Department of the Army, U.S. Army Medical Resetirch and Development Coremand, op. cit., footnote 5, p. 7-15.52 G- E&fi vice pr~ident for operations, Connaught Laboratories (Svfifhvater, IA), pUSO@ Commticatio% 1~.53 Ha&fl M~covi@ “verification of High-Containment Facil.itiea,” S.J. Lund@ cd., Views on Possible Verification Measures for theBiological Weapons Convention (Oxford, England: SIPRI/Oxford University Preas, 1991), p. 55.

Chapter 3-Technical Aspects of Biological Weapon Proliferation | 93and high-energy ultraviolet radiation; and chemicaltreatment with formaldehyde or bleach. 54Sophisticated biotechnology plants often haveself-sterilizing fermenters and process equipment,whether or not they are handling hazardous microorganisms.Such plants would therefore have aninherent capability to work with BTW agents.| Stabilization of BTW AgentsOnce BTW agents have been produced, it isnecessary to process them into a form thatenhances their stability in storage and afterdissemination, so that they remain viable longenough to infect. Since microbial pathogens areliving organisms, they will eventually deteriorateand die unless their metabolism is slowed downor stopped. Such a process of suspended animationoccurs naturally in the case of spore-formingmicroorganisms such as anthrax, which cansurvive for decades in the dormant spore form.Nonspore-forming microbes and most toxins,however, tend to break down rapidly in theenvironment if not protected. For this reason,BTW agents are generally most effective ifdisseminated within a few days after production.If rapid use is not feasible, the live agents must beconverted into a more stable form so that they cansurvive the stresses of storage, transport, anddissemination.FREEZE-DRYINGOne method for enhancing the stability ofBTW agents is rapid freezing and subsequentdehydration under a high vacuum, a processknown as freeze-drying or lyophilization. In a fewhours, a lyophilizer, a device mainly used in thepharmaceutical industry, reduces a solution ofbacteria and a sugar stabilizer to a small cake ofdried material that can then be milled into anydesired state of freeness. Lyophilization avoidsthe need to maintain microorganisms in inconvenientand dangerous liquid suspensions duringstorage and transportation. It also makes possiblea significant increase in agent potency by directinhalation of particles of dried agent into thelungs. 55 This technique is also applicable totoxins; a fine dust of dried toxin, if inhaled, can bedeadly in extremely small quantities.If kept in cold storage, the desiccated organismswill remain viable for long periods, althoughthey still deteriorate. For example, freezedriedbrucellosis bacteria can be stored for severalmonths, and Q-fever rickettsiae for up to 8years.56 Lyophilization alSO extends the shelf-lifeof protein toxins: freeze-dried Staphylococcusenterotoxin B (SEB) can be stored for up to a year.Even so, the virulence and viability of lyophilizedBTW agents decays over time: there is a loss ofpotency of a factor of 10 to 100 over a period of1 to 5 years, so that much larger quantities of olderagent are required to produce the same militaryeffect. 57CHEMICAL ADDITIVESThe stability of a microbial aerosol can beincreased by adding a variety of compounds to thespray material. 58 Moreover, antiagglomerants suchas colloidal silica help prevent the clumping offreeze-dried microbial agents and toxins that havebeen milled into a fine powder. Agriculturalresearch on biological pesticides, such as theinsect-killing bacterium Bacillus thuringiensis,has provided much information on methods forstabilizing bacterial agents in the field. Forexample, new formulations of B. thuringiensishave been developed that extend the life of the~ DW~ent of my, U.S, AI-My MedicaJ Research and Development Co remand, op. cit., footnote 5, pp. A-132, A-13-3.55 WIiH~ ad Wfice, op. cit., footnote 35, p. 72.SC Rotichild, op. cit., foo~ote 9, pp. 206-219.57 SPRI, VO1. VI, op. cit., foomote 31, p. 50.58 Row J. Goodlo~ ~d F~~c A. ~~, “Viability and I.nfcctivity of Microorganisms in Experimental Airborne InfectiorL”Bacteriological Reviews, vol. 25, 1%1, p. 185.

94 | Technologies Underlying Weapons of Mass Destructiondisseminated bacteria by means of ultravioletprotestants and other additives that ensure compatibilitywith existing agricultural sprayers. 59MICROENCAPSULATIONAnother approach to stabilization, known asmicroencapsulation, emulates natural spore formationby coating droplets of pathogens orparticles of toxin with a thin coat of gelatin,sodium alginate, cellulose, or some other protectivematerial. (An industrial example of microencapsulationis the production of carbonless carbonpaper, in which ink droplets are coated in thismanner.) Microencapsulation can be performedwith physical or chemical methods. 60Micromcapsulation production methods canbe set up to generate particles of a selected sizerange (e.g., 5 to 10 microns). 6l The polymercoating protects the infectious agent againstenvironmental stresses such as desiccation, sunlight,freezing, and the mechanical stresses ofdissemination, and permits cold-storage of microbialpathogens for several months. Microcapsulescan be charged electrostatically to reduce particleclumping during dissemination, or ultravioletlightblocking pigments can be added to themicrocapsule to protect microorganisms againstdegradation by sunlight. Once in the targetenvironment, such as the interior of the lung, thepolymer coating dissolves, releasing the agent.Microencapsulation can also be applied to toxins,making them more stable, predictable, and saferto handle.| Integration With Delivery SystemsA biological or toxin agent is of little militaryutility if it does not produce consistent andreliable effects and cannot be delivered to a target.BTW agents are all nonvolatile solids that wouldbe disseminated either as a liquid slurry or a drypowder of freeze-dried organisms or toxin. 62Possible delivery systems range in complexityand effectiveness from an agricultural sprayermounted on a truck to a specialized clusterwarhead carried on a ballistic missile. Thedifficulty of delivery-system development dependson the proliferant’s military objectives.It is not hard to spread BTW agents in anindiscriminate way for the purpose of producinglarge numbers of casualties over a widearea. It is much more difficult, however, todevelop BTW munitions that have predictableor controllable military effects against pointtargets, such as troop concentrations on thebattlefield.Many pathogens infect man naturally by meansof an intermediary organism (“vector’ ‘), such asa mosquito or tick. 63 Military microbiologistsdiscovered during World War II, however, thatBTW agents can be disseminated through the air,making it possible to infect large numbers ofpeople simultaneously. Many microbial pathogensand toxins-even those normally transmittedby vectors or in food-can invade the bodythrough the lungs, giving rise to foci of infectionor traveling through the bloodstream to otherparts of the body. The key to producing large-59 ~Ve~nt of the United Kingdom, ‘‘General Developments Relevant to the BWC,’ in Background Document on New Scientific andTechnological DevelopmentsRelevant to the Convention on the Prohibition of the Development, Production and Stockpiling ofBacteriological(Biological) and Toxin Weapons and on Their Destruction, Third Review Conference of the BWC (Genev& Switzerland), Document No.BWC/CONF.111/4, Aug. 26, 1991, p. 25.@ -U OSO1 et al,, eds., Remington’s Pharmuceutica2 Sciences, 15th ed. (Eastou PA: M@ mbl- CO., 1975), P. 1604.61 A ~c.n iS ~ ~ou~th of a fi~eter.62 C.V. Chester and G. P. Ziummnaq ‘‘Civil Defense hnplieat.ions Of Biological WMPOIIS,” Journal of Civil De$ense, vol. 17, No, 6,December 1984, p. 6.63 me disme v~~r is usually some type of arthropod: mosquitoes ~“t yellow fever and dengue fevw, fleas transmit plague; and tickstransmit tularernia and Q fever, During 1932-45, the Japan~e BW facility known as Unit 731 set up flea “nurseries” for the production of135 miUion plague-infested fleas every 4 months. As a delivexy systenA porcelain bombs were developed that could contain about 30,000infected fleas. See Williams and Wallace, op. cit., footnote 35, p. 27.

Chapter 3–Technical Aspects of Biological Weapon Proliferation | 95scale respiratory infections is to generate abiological “aerosol”: a stable cloud of suspendedmicroscopic droplets, each containingfrom one to thousands of bacterial or virusparticles. (Fogs and smokes are examples ofvisible aerosols.) Biological aerosols can beproduced with a relatively simple piece of machinery,analogous to a home vaporizer, thatsprays a suspension of microorganisms throughfine nozzles, converting about 85 percent of theirstarting material into droplets in the desired sizerange. 64 The concentration of organisms in thestarting solution influences the distribution oforganisms among the aerosol particles. 65Aerosol dissemination of many vector-bornediseases, such as yellow fever, Rocky Mountainspotted fever, tularemia, and tick-borne encephalitis,can produce atypical infections of therespiratory tract. Respiratory infection with suchagents bypasses normal protective mechanismssuch as local inflammatory processes and increasesthe virulence of pathogens that normallyhave a low lethality, such as Venezuelan equineencephalitis (VEE). 66 In the case of microbialpathogens that can be transmitted by differentroutes, such as anthrax bacteria, respiratory infectionresults in by far the most virulent form of thedisease. For example, whereas untreated skinanthrax is fatal in only about 5 percent of cases,pulmonary anthrax is fatal in more than 90percent of cases. 67Freeze-dried toxins can also be disseminated inthe form of an aerosol. Recent studies have shownthat saxitoxin and T-2 trichothecene mycotoxinare at least 10 times more toxic when administeredby aerosol than by intravenous injection. 68Because protein toxins are large organic molecules,however, they are susceptible to environmentalstresses such as heat, oxidation, and shearforces. As a result, attempts to aerosolize toxinshave encountered problems in maintainingg thestability of the agent before and after dissemination.It is also difficult to formulate protein toxinscapable of penetrating the skin.The primary challenge in weaponizing BTWagents for long-range delivery is to keep themalive long enough to infect enemy troops. Theagent must be capable of withstanding thephysical stresses involved in the disseminationprocess without losing activity. Technical hurdlesinvolved in the design of self-dispensingbiological weapons are as follows:■the munition or delivery system must generatea cloud of aerosol particles with dimensionsthat allow them to be inhaled deep intothe lungs of the target personnel;the agent must be physically stabilized sothat it can survive the process of disseminationlong enough to infect the target personnel;the agent must disseminated slowly to permitaerosolization while avoiding loss of viabilityor toxicity; andthe overall size and shape of the aerosolcloud and the concentration of agent withinit must be reasonably predictable, so that thedispersion pattern can be matched to thetarget. 69These technical hurdles are discussed below.64 Wton Lcitenberg, “Biological Weapons, ’ Scientist and Citizen, vol. 9, No. 7, August-September 1%7, p. 157.65 Goodlow and Leonard, op. cit., footnote 58, p. 1*4.66 World He~~ org~=tiom Hea/~h A~pecr~ ~~C~em”ca/ and Biological Weapons (Geneva: W-lo, 1970), p. 61.ST ~llcoff, op. cit., footnote 29.68 Gove~ent of the U. S. S. R., “Selected Scientific and Technological Developments of Relevance to the BW Convention” op. cit.,footnote 43, p. A lO.69 stoc~o~ Intemtio~ pe~e Re~em~h Imti~te (SrpRr), The Problem of chemical andBiOIOgical wa~are, VOI. II: CB wt?clpO?lS TOC@I(Stockholm: Alrnqvist & WikeH, 1973), pp. 72-73.

96 | Technologies Underlying Weapons of Mass DestructionEFFECT OF PARTICLE SIZEThe particle size of an aerosol is critical to bothits atmospheric stability and its military effectiveness.Whereas larger particles tend to settle out ofthe air, microscopic particles between one andfive microns in diameter form a stable aerosol inwhich the particles remain airborne for a longtime. The very low settling velocity of theparticles will by itself keep a biological aerosolcloud suspended in the air for long periods. Sucha cloud may therefore be transported by the windover long distances. Moreover, losses resultingfrom fallout and washout are negligible and donot significantly reduce the concentration of anaerosol cloud. Particles less than 5 microns indiameter generally do not collide with smoothsurfaces in their path but are carried over them byair currents. In contrast, transport over roughsurfaces for distances of more than a kilometercan result in significant deposition.Aerosolized BTW agents generally do notpenetrate the skin and thus do not represent asignificant contact hazard; instead, they infectindividuals only if inhaled into the lungs .70Particle size is also critical for respiratory infection.Almost all particles larger than 5 microns indiameter are trapped in the phlegm and passagesof the upper respiratory tract, while particlessmaller than 1 micron diameter are exhaledwithout being retained in the deep lung tissue.Only particles between 1 and 5 microns indiameter are small enough to reach the tinyterminal air sacs (alveoli) of the lung, bypassingthe body’s natural filtering and defense mechanisms.In one set of experiments on the effect ofparticle size on respiratory infection, tularemiabacteria were administered to guinea pigs as anaerosol. When the aerosol. particles were 1 micronin diameter, only 3 bacterial cells per animal wereneeded to kill 50 percent of the guinea pigs, butwhen the particle size was increased to 7 microns,the number of bacteria per animal required to killhalf of the guinea pigs rose to 6,500. 71PHYSICAL STABILIZATIONThe use of mechanical devices to generateaerosols from a bulk storage tank places a varietyof mechanical stresses on microorganisms, reducingthe number of viable, infectious cells. Relativelyfew microbial pathogens can meet thestability requirements of bulk dissemination. 72Those agents best suited for long-range attack caninfect with a small number of microorganismsand are hardy enough to survive for a fairly longperiod floating in the air. Once released, however,the aerosol cloud “decays” over time as themicroorganisms die as a result of exposure tooxygen, atmospheric pollutants, sunlight, anddesiccation, resulting in a loss of viability (abilityto survive and multiply) and virulence (ability tocause disease and injury). A BW agent disseminatedinto a given environment may also retain itsviability while losing its virulence. 73Decay of an aerosol cloud occurs in two stages.Initial dissemination is followed by a period ofvery rapid cell death during the first severalseconds after the cloud has been released. Indeed,producing a liquid aerosol by explosive dispersionor passage through a spray device may kill asmany as 95 percent of the microorganisms. Thisinitial stage is followed by a much slower rate ofdecay, so that the aerosol cloud may persist forlong periods of time. A relative humidity of over70 percent promotes microbial survival. 74 Largeparticleclouds are more resistant to the lethaleffects of solar radiation than small-particle70 Ibid., p. 29.71 ~j. WiU~ D. Sawy=, “Airborne rnfectiom” Military Medicine, February 1%3, pp. 90-92.72 SIPRI, VOI. II, op. cit., footnote 69, p. 30.73 *UP of com~~t ~p~ on ~efic~ ~d Bacteriolo@~ @iolo@@ WqXMM, Chem”cal ati Bacteriological (Biological)Weapons and the Z2’ecrs of Their /Dossible Use, United Nations Report No. E.69.I.24 (New York NY: Ballantine Books, 1970), p. 13.74 r)q~ent of the AIIIy, U.S. Army Medical Research md Development CO mman~ op. cit., footnote 5, p. A7-16.

Chapter 3-Technical Aspects of Biological Weapon Proliferation! 97clouds, and dry disseminated aerosols are moreresistant than wet aerosols. 75 As the plumedisperses, long-lived particles (e.g., anthraxspores) may be deposited on the ground, wherethey may then adhere to large particles of surfacesoil and dust. If the surface is disturbed, either bythe wind or by human activities, the spores canagain be resuspended, potentially causing additionalinfections. 76 The inhalation hazard is muchreduced, however, owing to the large particle size.TYPES OF AEROSOL ATTACKSThere are two types of aerosol dissemination ofBTW agents. “Area” attack involves releasingan aerosol cloud upwind and allowing it to driftover the target area. In contrast, “point” attackinvolves projecting the agent in a cannister thatreleases the agent immediately over the target. 77Area attackA BTW weapon designed for area attack woulddisseminate its payload as an aerosol cloudcontaining a sufficient concentration of viablemicroorganisms to infect the targeted personnelwith particles in the 1 to 5 micron size range. Thesimplest means of area delivery is with spraytanks mounted on manned aircraft, unmannedremotely piloted vehicles (RPVs), or cruisemissiles, which can release a large quantity ofagent over a controlled line of flight. A slowflyingaircraft such as a crop duster coulddischarge a line of agent that, as it travelleddownwind, would reach the ground as a vast,elongated infective cloud. Such a linear cloud ofagent, known as a ‘‘line source, can cover alarger area than a cloud released from a singlespot, or ‘‘point source. ’Air rushing past the spray tank can be used toforce out its contents; alternatively, compressedair or carbon dioxide may be used to disseminatethe agent. Aerosol generators might also beoperated from offshore ships or submarines parallelto a coastline, producing an invisible cloud ofBTW agents that could be carried by the prevailingwinds over key coastal cities or militarybases. 78 The discharge rate must be slow enoughto generate a stable aerosol, yet slow-flyingaircraft and RPVs are extremely vulnerable to airdefenses.Area attack with a biological aerosol dependsheavily on atmospheric diffusion and wind currentsto dilute and spread the agent over the areabeing attacked. The most stable atmosphericconditions occur on cold, clear nights or early inthe morning, when the ground and the layer of airabove it are cooler than the next higher 1ayer ofair. This phenomenon, called an inversion, isideal for the delivery of BTW agents because thestable interface of warm and cold air prevents thevertical mixing of the cloud and causes it to hugthe ground, keeping the organisms at a lowaltitude where they can be inhaled. In contrast,bright sunlight causes atmospheric turbulencethat breaks up the aerosol cloud, and also containsultraviolet rays that kill many microorganisms.For these reasons, a BTW attack would be mostlikely to come at dusk or at night. 79The effectiveness of an area attack also requiresdetailed knowledge of the prevailing winddirection and speed. Under favorable wind conditions,an aerosol cloud could contaminate the airover large areas, but if the wind is erratic orexcessively strong, the agent might fail to reachthe target or might be dissipated too rapidly to be75 G@ow and bonard, op. cit., footnote 58, p. 184.76 ~onB~Wige,~n~a/ation HUardfiom Reaero$o/izedBio/ogicalAgent$:A Review, Repod No. ~EC-l_’R~13 (A~rd@nprov@Ground, MD: Chemical Research, Development and Engineering Center, September 1992).77 SIPRI, vol. II, op. cit., footnote 69, p. 28.78 W, Seth cm, “The poor Man’s Atomic Bo&?”: Biological Weapons in the Middle East, Washington IDstitute Policy Papers No. 23(WashingtorL DC: Washington Institute for Near East Policy, 1991), p. 11.79 ~ester ~d zimme= op. cit., footnote 62, P. 7.

98 | Technologies Underlying Weapons of Mass Destructioneffective. Assuming the target is nearby, theattackers will know the wind direction and canplan the attack at a favorable time. If the target isdeep inside enemy territory, local meteorologicalconditions would be harder to assess withoutaccess to current weather data. Nevertheless,hundreds of airports worldwide broadcast winddirection, speed, cloud cover, and temperatureevery 3 hours according to World MeteorologicalOrganization guidelines.A remotely piloted vehicle or subsonic cruisemissile flying at low altitude might reduce suchproblems by disseminating the toxic cloudclose to the ground just upwind of the target—assuming, of course, that the attacker had themeans of knowing which way the wind wasblowing over the target area. In 1960, the U.S.Army began developing a drone aircraft thatcould be used to deliver chemical and biologicalweapons. The pilotless plane was designed tocarry 200 pounds of germ agents as far as 115miles. 80 Even relatively unsophisticated cruisemissiles might be capable of generating linesourceaerosols for off-target attacks. 81 For thisreason, the simultaneous proliferation of biologicalweapons and cruise-missile capabilitiesmay become a major security threat in thefuture.Point attackA point BTW attack would be performed withmunitions delivered by artillery, rockets, missiles,or aircraft. Although the targeted personnelwould be warned of the attack by the arrival of themunition, the rapid formation of a concentratedaerosol (within 15 to 30 seconds) means thatmany soldiers would inhale an incapacitating orlethal dose of agent before they had time to put ontheir gas masks properly, assuming they wereavailable. 82 A point attack that dropped the agentdirectly over the targeted personnel would also bemuch less dependent on meteorological conditions,although it would require a much higherpayload of munitions per area covered.MUNITIONS FOR POINT ATTACKMunitions developed for chemical-warfare agentsare generally unsuited for biological warfarebecause of the lower stability of BTW agents andtheir susceptibility to environmental factors suchas ultraviolet radiation and air pollution. Thereare two basic methods for disseminating BTWagents from a munition: explosive and pressurized.Whereas explosive dissemination producesan almost instantaneous build-up of aerosolconcentration over the target, it destroys a largeportion of the infectious agents and tends toproduce drops that are considerably larger thanthe optimal droplet size for inhalation. 83 Incontrast, pressurized munitions do not disperseagent as rapidly as explosive munitions butprovide better control of particle size, are gentleron the microorganisms, and produce an aerosolcloud that is visible for a shorter period of time.One method of pressurized delivery is to force aliquid suspension of agent through a fine nozzle,which breaks up the material into droplets of theappropriate size.A BTW bomb or warhead may either befilled with bulk agent or with numerousself-dispensing cluster-bomb units (CBUs). Acluster bomb has a casing that breaks open duringdelivery to scatter a large number of smallersubmunitions over a wide area. The submunitionsthen fall to earth and are triggered to go off at analtitude of about 15 to 20 feet off the ground. Eachof these bomblets generates a small aerosol cloud;these multiple point sources are then coalesced byair currents into a single large cloud. DuringWorld War II, the United States and Great Britain80 I-k@ op. cit., foo~ote 41, .P. 71.al ~, op. cit., foomote 78, PP. 1o11.82 Rowhild, op. cit., footnote 9, p. 76.83 Ibid., p. 60.

Chapter 3-Technical Aspects of Biological Weapon Proliferation 199jointly developed a 500-pound bomb for thedelivery of anthrax spores. Each bomb casingcontained 106 four-pound bomblets designed toburst in midair, producing dense aerosols ofspores. Twenty of these bomblets could cause ahigh fatality rate among humans and livestockover a one-square-mile area, and British war planscalled for using as many as 40,000 anthrax bombsagainst six German cities. 84Nevertheless, the technical difficulty of dispensingsubmunitions should not be underestimated.Missile delivery would place severe environmentalstresses on microbial agents, includingfreezing temperatures prevailing at high altitudesand friction-heating of the missile noseconeduring reentry through the atmosphere, whichcould be fatal to microbes without sufficientinsulation. The timing of agent disseminationwould also be critical, since if it occurred at thewrong altitude, the agent would not form amilitarily effective aerosol. Releasing the agenttoo high would cause it to dissipate before it couldbe inhaled by the targeted troops; releasing it toolow would merely produce a puddle of toxicmaterial on the ground. In sum, effective agentdissemination requires a series of mechanicalsteps to work perfectly, and atmospheric conditionsto cooperate.Other problems associated with weaponizationinclude the hazards of loading munitions withagent, and corrosion and seepage from filledmunitions. Despite these technical hurdles, however,effective biological munitions have beendeveloped and deployed in the past. In 1951, thefirst anticrop cluster bombs were placed inproduction for the U.S. Air Force; each bombletcontained turkey feathers centaminated with cerealrust spores. 85 Also during the 1950s, theUnited States developed small, self-dispersingBTW bomblets for the Honest John missile. 86In conclusion, strategic BTW attacks againstcities might be carried out with relatively simpleoff-target delivery systems, such as a spray tankcarried by an aircraft. After dissemination, theaerosol cloud might behave in unexpected waysin response to changes in the wind and weather,potentially boomeranging against the attacker’sown troops or population. 87 More controlled pointattacks with BTW agents for military purposeswould require the use of missiles or bombs,possibly equipped with cluster munitions, butsuch attacks would be technically more difficultto carry out.Some analysts contend that the most probableuse of BTW agents would be for covert warfareagainst crops, livestock, or human populations forpurposes of economic destabilization. In thiscase, relatively small quantities of BTW agentsmight be introduced by human saboteurs directlyinto the air or water supply of a city or militaryinstallation.INDICATORS OF BTW AGENTPRODUCTIONDetection and monitoring of BTW agent productionis an extremely challenging task for thefollowing reasons:■ All equipment and feedstock materials usedto make BTW agents is dual-use and couldbe used for legitimate purposes in the biotechnologyor pharmaceutical industries.■ Utilizing new biotechnologies, productioncould take place in facilities that are muchsmaller and less conspicuous than in the past,84 Barton J. Berstein, “Churchill’s Secret Biological Weapons,” Bulletin of the Atomic Scientists, January/February 1987, pp. 4&50.85 SIPRI, VO1. II, op. cit., footnote 69, p. 160.86 Rothschild, op. cit., footnote 9, p. 78.87 h 1942, dtig World War II, special Japanese troops spread diseases such as cholera, typhoi~ plague, ~d ~~ ~ -.Subsequently, more than 10,000 Japanese soldiers fell ill after they overran a contamma “ ted are% presuma bly because regular soldiers had notbeen informed about the use of biological weapons. Barend ter Haar, The Future of Biological Weapons, The Washington Papers No. 151 (NewYork NY: Praeger, 1991), p. 5.

100 I Technologies Underlying Weapons of Mass Destructionwith no obvious signs to indicate illicitactivity.■ Legitimate facilities might be diverted to theproduction of BTW agents in a relativelyshort time.■ Since microbial agents can be grown in anadvanced fermenter from a few cells to manykilograms of agent over a period of days orweeks, it would not be necessary to maintainlarge stockpiles (although filled or emptymunitions would need to be stored).The extreme potency of BTW agents meansthat as little as a few kilograms can bemilitarily significant.■ BTW agents would be hard to distinguishfrom naturally occurring pathogens, particularlyif the agents are endemic to the affectedarea.There is an enormous variety of potentialBTW agents, each requiring a specific detectionmethod. 88According to a State Department official, “Inmany ways, recent progress in biological technologyincreases the ease of concealment of illicitmanufacturing plants, particularly for biologicallyderived chemicals such as toxins. . . . Notonly has the time from basic research to massproduction decreased but the ability to createagents and toxins with more optimal weaponpotential has increased. Simply put, the potentialfor undetected breakout from treaty constraintshas increased significantly.” 89 Thus, while thecharacteristics of a given facility may be consistentwith an offensive BTW program, the odds offinding a “smoking gun’’ -such as a munitionfilled with BTW agent—are quite low.Despite these difficulties, however, a fewfactors constrain the detection problem. Microbialpathogens and toxins of military concernhave relatively few civilian uses in scientificresearch and medical therapy, and such applicationsare generally confined to sophisticatedbiomedical research centers not often found indeveloping countries. As a result, there are someproduction and weaponization signatures that-ifintegrated effectively with national intelligencecollection and declarations of activities andfacilities relevant to the Biological and ToxinWeapons Convention-might provide strong circumstantialevidence of a clandestine BTWprogram.| Research and Development SignaturesMany research and development activitiesrelated to BTW agents are inherently ambiguousin that they can support both defensive andoffensive purposes. It is therefore essential toevaluate the evidence in the context of a countryoverall behavior and the openness and transparencyof its nominally defensive program. Telltaleindicators of a BTW program might include theexistence of biological research facilities operatedunder military control, the large-scale productionof vaccines in excess of legitimatedomestic needs, or the purchase of dual-usebiological materials and equipment. Analystssearching for indicators of foreign BTW activitiesshould avoid “mirror-imaging’ ‘—the temptationto judge other countries by U.S. standards. Onlyby first understanding a country’s commercialstandards for biological containment and goodmanufacturing practice is it possible to identifyanomalies that do not fit this basic profile. 90SCIENTIFIC PUBLICATIONSThe collection and systematic analysis ofscientific and technical information published bya country of proliferation concern can help toS6 stwhen S, Morse, ‘‘Strategies for Biological Weapons Verification” Proceedings of the Arms Control and Verification TechnologyConference, Williamsburg, VA, June 1992 (Washingtoxq DC: Defense Nuclear Ageney, in press.)69 H. Allen Ho~es, “Biolo@c~ WM~ns proliferatio~” Department of Sfate Bufkrin, VO1. 89, JulY 1989, p. 43.w Graham S. Pearsoq ‘Biological Weapons: ~ British View,’ p=sentation at a Seminar on Biological Weapons in the 1990s, sponsoredby the Center for Strategic and International Studies, Washington DC, Nov. 4, 1992.

Chapter 3-Technical Aspects of Biological Weapon Proliferation I 101monitor research trends, identify institutions andscientists associated with such research activities(including cooperation with foreign states), andidentify gaps or abrupt halts in open research onparticular topics that may be suggestive ofmilitary censorship. Although such literatureanalysis is unlikely to reveal BTW activities thathave been deliberately concealed, it can raisequestions about the capabilities and activities ofvarious facilities and is useful when combinedwith other sources of information. For example,useful intelligence on Soviet BW activities wasreportedly gleaned from clues picked up in theSoviet scientific literature. By tracking the awardof academic honors and by noticing obvious gapsin a series of published papers, Western intelligenceanalysts could judge which fields ofbiological research Soviet military scientists hadentered. 91 During the 1970s and ‘80s, for example,the Soviet literature contained a remarkablylarge number of publications on toxin research. 92Nevertheless, publication tracking is not areliable indicator of a BTW program. First, itrequires the existence of a preliminary scientificresearch effort before a country undertakes productionof BTW agents. In the past, countries withoffensive BTW programs, such as Japan, Germany,the United States, and the Soviet Union,launched a major scientific research effort inrelevant areas of microbiology before they coulddevelop biological weapons. Today, however,much of the basic science is already well understood,and explicit weapon-development programscould be undertaken with relatively littlepreliminary research.Second, because many variables affect scientificproductivity and publication rates, publicationtracking can only provide a broad indicationof a state’s BTW activities. The scientific culturein many developing countries does not demandlarge numbers of publications, so there will befewer to monitor. Finally, the biomedical databasesavailable for tracking (e.g., MEDLINE) donot have representative numbers of scientificabstracts from the countries of greatest proliferationconcern, particularly for papers not publishedin English. 93 For this reason, the number ofabstracts in the database dealing with microbialand toxin agents may not correlate either positivelyor negatively with a country’s BTWactivities. For all these reasons, publication analysisis an unreliable-although potentially useful—indicator of BTW activity.HUMAN INTELLIGENCEBecause of the limited value of technicalcollection systems such as satellites for monitoringBTW activities, human intelligence is vital inthis area. For example, Vladimir Pasechnik, aRussian microbiologist with first-hand knowledgeof the Soviet BTW program, defected toBritain in 1989 while attending a scientificconference in London and provided extensiveinformation on Soviet BTW activities that wasunobtainable by other means. 94 Human agentsand defectors can also confirm suspicions aboutsites and activities based on other sources ofintelligence. Nevertheless, the UNSCOM biologicalinspections of Iraq have shown that humanintelligence can be unreliable or misleading if theindividual reporting does not have direct knowledgeor is unfamiliar with the technical details ofwhat he is describing. 9591 Harris and Paxman, op. cit., foomote 14, p. 114.92 David B&r, “~emi~~ ~d Biologic~ w~~e Agen~_AFre~App~~~’ Ja~e’~J~re//~ge~ceReview, VO]. s, ~0, ~, ~a13~ 199s,p. 44.w ~licoff, op. cit., foomote 29.1992.94 Bin Gem, “Defecting Russian Scientist Revealed Biological - ~ofis,” The Washington Times, July 4, 1992, p. A4.95 ~lqhone fitwiw ~~ David H~soll, de- S~hOol of Vete- Medicine, ~~.s@ Swte Un.iversiv, Baton Rouge, ~, Aug. 17,

102 I Technologies Underlying Weapons of Mass Destruction| Weaponization and Testing SignaturesWeaponization involves the determination ofwhether a candidate BTW agent is militarilyeffective and how it would be used. Theseactivities have no obvious civilian counterpart,and hence would be indicative of a clandestineBTW development program. Signatures associatedwith the testing of candidate BTW agentsmight be easier to detect than agent productionsignatures, and inspections focusing on weaponizationactivities would also be more acceptable tothe biotechnology industry than production monitoring,since they would not compromise tradesecrets.Examples of weaponization and testing signaturesthat might be observable with overheadphotography include field tests of aerosol dispersalpatterns, tests of effectiveness against largeanimals, and the surreptitious burial of deadanimals from weaponization tests .96 Other weaponizationsignatures would only be visibleduring an onsite inspection. For example, specializedaerosol test chambers might be used tostudy the behavior of biological aerosols in theenvironment or the detonation of BTW munitions.If such a test facility were found in anominally civilian vaccine plant, it would beextremely suspicious. Indeed, the secret SovietBW facility at the All-Union Research Institute ofApplied Microbiology in Oblensk reportedlycontained two such test chambers. The “aerosoldisseminationtest chamber’ consisted of a steelcube, roughly 50 feet on a side, in whichexperimental animals were tethered to the floorand exposed to BW aerosols released from ceilingvents. There was also a reinforced ‘‘explosivetestchamber’ in which the detonation of BWmunitions was simulated. 97Although some analysts contend that weaponizationcould be carried out in enclosed,unobtrusive facilities, others argue that theintegration of signatures from a variety ofsources would make a militarily significantweaponization program difficult to hide. Nevertheless,there are a number of potential concealmentstrategies:Weaponization studies short of actual fieldtests could be performed inside productionfacilities.Open-air testing of BTW weapons would bedifficult to detect if the test grid weremasked, or if there were no distinctivedelivery systems or advance indications ofwhere to look. In addition, since many BTWagents are sensitive to sunlight, they wouldbe tested at night. 98Certain legitimate activities, such as thedissemination of biopesticides on crops, orthe use of conventional smoke bombs, mightbe used as a cover for BTW weaponizationtesting.growing number of countries, for example,are replacing chemical pesticides with certainmicroorganisms that are natural insect-killers.Although over 100 bacteria, fungi, and virusesinfect insects, only a very few are in commercialproduction. The most widely used is Bacillusthuringiensis, a bacterium that produces a crystallineprotein toxic to insects and is applied to cropsas an aerosol from agricultural sprayers. 99 AlthoughB. thuringiensis does not have the characteristicsof a BW agent and would be a poorsimulant for weaponization studies, field testswith bacteria more closely resembling BW agentscould be disguised as biopesticide application.Thus, if biopesticides are already in use in the96 Rst rmges will Mely be at remote locations. The former Soviet UnioW for example, operated a BTW test site on isolated VO~fideniyeIsland in the Aral Sea.97 John Bamy, “P1 arming a Plague?” Newsweek, Feb. 1, 1993, p. 40.‘3S J~es -s, Engines of Wlzr: Merchants of Death and the New Arms Race (New Yor& NY: Atlantic Monthly press, 1990), P. 221.99 primrose, op. cit., footnote 42, P. 76+

Chapter 3-Technical Aspects of Biological Weapon Proliferation I 103local agricultural sector, a covert proliferant coulduse them to test the open-air dissemination ofmicrobial aerosols in preparation for germ warfare,and also to justify the acquisition of hardwareneeded to disperse the agent. Nevertheless,substantial field tests using grams or kilograms ofmicron-sized particles could be detected in samplestaken at great distances downwind if theorganism had distinctive DNA sequences andthose doing the detection knew what to look for.| Production SignaturesProduction of BTW agents is nearly impossibleto detect by visual inspection alone, although thisapproach may add some useful pieces to thepuzzle.EXTERNAL VISUAL SIGNATURESBTW production facilities may sometimes bedetected or monitored with overhead photography,although the evidence is nearly alwaysambiguous. For example, the Institute of Microbiologyand Virology in the Russian city ofSverdlovsk, 850 miles east of Moscow, reportedlyaroused the suspicions of U.S. intelligenceanalysts in the 1970s because of certain characteristicsobserved by satellite. Photointerpretersidentified tall incinerator stacks, large coldstoragefacilities, animal pens, sentries, anddouble barbed-wire fences. These features, notunlike those at the former U.S. offensive BTWfacility at Fort Detrick, suggested that theSverdlovsk facility might serve military purposes.100 In Much 1980, the U.S. Governmentattributed a serious outbreak of pulmonary anthraxin Sverdlovsk the previous year to SovietBW activities at the microbiology institute. AlthoughSoviet officials denied the allegations atthe time, in May 1992 Russian President BorisYeltsin finally admitted that the anthrax epidemichad been caused by an accident at the militaryfacility. Russian military spokesmen have insisted,however, that the anthrax work atSverdlovsk was “defensive” in nature, and thisquestion has yet to be resolved. l0lRecent innovations in biotechnological productiontechnology aimed at increasing productivity,cutting costs, and improving safety havefurther blurred distinctions important for verification,such as between a laboratory and a productionfacility. In the past, large batch fermentersand refrigerated storage vaults provided signaturesof BTW production; today they are beingreplaced in advanced industrial countries withsmall, continuous-flow fermenters that can producelarge quantities of highly infectious materialsrapidly in a laboratory-scale facility. Suchadvances in production technology have greatlyincreased the difficulty of detection by reducingthe size of plants needed to producemilitarily significant quantities of BTW agentsand the amount of time needed to break out ofdisarmed status. With the new production technologies,a clandestine BTW plant might be moreeasily camouflaged, buried underground, or hiddenwithin a larger complex that produces legitimatecommercial products.Still, satellite or aerial photography might helpto monitor sites judged suspicious on the basis ofother sources of intelligence. The followingsignatures of BTW agent production might bedetected or monitored with overhead imaging:“Excessive” secrecy and security surroundinga nominally civilian microbiologicalfacility, such as a brewery, sugar refinery,infant-formula plant, or single-cell proteinplant. Telltale security measures might includedouble or triple fencing, watch towers,IW Elisa D. Harris, “Sverdlovsk and Yellow Rain: Two Cases of Soviet Noncompliance?” International Secun”fy, vol. 11, No. 4, spring1987, pp. 41-95.Iol See Milton Leitenberg, “A Return to Sverdlovsk: Allegations of Soviet Activities Related to Biological Weapons,’ Arms Control, vol.12, No. 2, September 1991 ($mblished April 1992), pp. 161-190; and Milton Leitenberg, “Anthraz in Sverdlovsk: New Pieees to the Puzzle, ”Arms Control Toa2zy, vol. 22, No. 3, April 1992, pp. 1013.

104 I Technologies Underlying Weapons of Mass Destructionand air-defense missile batteries-althoughconcealment, camouflage, and deception operationsare possible.Elaborate microbiological production facilitiesinconsistent with the level of sophisticationof other, clearly civilian plants.Facilities for housing large numbers ofprimates, horses, rats, mice, rabbits, sheep,goats, or chickens (for producing eggs),when such animals are not clearly associatedwith vaccine production.Changes in activity at nominally civilianproduction facilities.PLANT DESIGN AND LAYOUTOther signatures of BTW production would notbe visible from outside a suspect facility, and thuscould only be detected during an intrusive onsiteinspection. The basic equipment in a BTWproduction facility would be much the same asthat in a vaccine plant, including equipment andmaterials for microbial fermentation, cell culture,or egg incubation, followed by harvesting, purification,and lyophilization. Both a vaccine plantand a BTW production facility would require asource of pharmaceutical-grade distilled water toremove bacterial contaminants in tap water thatwould interfere with the growth of desired microbialagents. And both types of facilities wouldrequire autoclaves to sterilize the growth mediaand decontaminate the equipment after production.It is also important to evaluate BTW-relatedactivities in their socioeconomic context. Indeveloped countries, civilian production facilitiesthat utilize microorganisms, such as pharmaceuticalplants and even breweries, now incorporatesafety and environmental equipment that wereonce unique to BTW production facilities. Thisfact has made it easier to use commercial productionas a cover for illicit military work, althoughthe presence in a vaccine-production plant ofprocesses that cannot be justified on technical oreconomic grounds may provide indicators ofpossible conversion or diversion to BTW production.Nevertheless, a clandestine BTW productionfacility could be so small that it could be easilyhidden.PHYSICAL CONTAINMENTIn developed countries, an important differencebetween a vaccine plant and a BTW productionfacility may be the level and type of physicalcontainment measures that are employed. Threeaspects of physical containment might be suggestiveof a clandestine BTW program:First, production of vaccines involves the useof living, attenuated microbial strains that areeither further weakened to produce a live vaccineor killed immediately after cultivation. As aresult, stringent containment measures are requiredonly during the initial phase of vaccineproduction, which involves the cultivation ofagents before they are attenuated or killed. 102According to one assessment, “Extensive safetyprecautions during the whole production cycle fora vaccine are hardly defensible economically andwould hence be suspect. ’ ’ 103A second difference between a vaccine plantand a BTW production facility is the presence inthe former of costly measures to protect thepurity, sterility, and reproducibility of the productsso that they are suitable for human use. Thus,an indicator of illicit BTW production in apharmaceutical facility might be the absence ofmeasures to purify the product and ensure itssterility.Although BTW agents would probably becultivated under negative pressure to preventdangerous microbes from escaping from theplant, this would not be a reliable signaturebecause negative pressure would also be neededIn David L, H~ol~ ~@ El. &ott, ~d Wik C. RI@icIK III, “Medicine in Defense Agtit Biological Wtime,’ yOIUd Of theAmerican Medical Association, vol. 262, No. 5, Aug. 4, 1989, p. 679.103 SH, VOI. VI, op. cit., footnote 31, p. 45.

Chapter 3-Technical Aspects of Biological Weapon Proliferation 1105in a legitimate pharmaceutical plant that isproducing live, attenuated vaccines. It would alsobe possible to reverse the pressurization of afacility before an inspection by changing thedirection of flow of the faltered air, but only if thesystem were engineered for this purpose inadvance. Moreover, governments engaged in thecovert production of BTW agents would probablynot hesitate to cut comers on containment andworker safety in order to avoid signaling theirintentions.In addition to the type and level of physicalcontainment, several other potential signatures ofclandestine BTW production might be detectedduring an onsite inspection. l04 The utility of suchsignatures is highly controversial, however, andeach one is open to criticism. These signaturesmight include:Bad odors associated with microbial fermentation,since multiplying bacteria produce avariety of volatile and odiferous gases.However, odors do not travel far and arenonspecific.Seed stocks and cell lines inappropriate fordeclared activities such as production ofvaccines or single-cell protein, or in amountsexceeding immediate research needs. However,such materials would probably not bedeclared and could be easily hidden.Activities related to microorganisms andtoxins that cannot be explained by civilianneeds, such as development of vaccinesagainst rare, nonindigenous disease agents.However, such activities could be easilyhidden.Production capacity greatly in excess ofdemand for the plant’s legitimate products,such as vaccines. However, such excesscapacity would not be required for a BTWcapability.A discrepancy between a small quantity ofoutput product (e.g., packaged vials of vaccine)and a large quantity of input materials(e.g., fermentation media). However, calculationof a precise material balance is probablyimpossible.Air compressors, air tanks, or lines forair-supplied protective suits as a means ofenhancing physical containment. However,compressors are easily hidden.Facilities for rapid decontamination andcleaning of the production line, or evidenceof recent large-scale decontamination operations,fumigation, or removal of materials orequipment. However, decontamination routinelyoccurs in pharmaceutical facilities.Large stockpiles of bleach (sodium hypochloriteor sodium hydroxide) for use as adecontaminating agent. However, such agentsare also widely used in legitimate commercialfacilities.Specialized equipment for the lyophilization,milling, or microencapsulation of BTWagents. However, lyophilization machinesare ubiquitous in the pharmaceutical indus-W.Refrigerated storage bunkers, freezers, orlarge quantities of liquid nitrogen for storingstockpiles of live or freeze-dried pathogens.However, since significant quantities ofbiological agents can be grown relativelyquickly, long-term stockpiling of agents inrefrigerated bunkers is unnecessary.Anomalous transport of microbial productsor wastes off-site. However, microbial wastecan be steam-sterilized.Incomplete or anomalous plant productionrecords. However, a proliferant engaged inillicit production is unlikely to provide suchrecords voluntarily. Records might also be1~ F@emtion of herican Scientists, Working Group on Biological and lbxin Weapons Verii3catioQ ‘‘A hgally BiIMI@ ComPl~ceRegime for the Biological Weapons Convention: Reftiment of Proposed Measures Through Trial Facility Visits,” draft manuscrip~ March1992, p. 12. See also SIPRI, vol. VI, op. cit., footnote 31, p. 35.

106 I Technologies Underlying Weapons of Mass Destructionforged, although it is hard to do so convincingly.Still, although the indicators listed abovewould not necessarily be associated with illicitproduction activities, a pattern of them mightarouse suspicions.BIOCHEMICAL SIGNATURESBTW agents do not possess a single commonchemical signature, such as the phosphorusmethylbond characteristic of most nerve agents,but pathogenic microorganisms can be identifiedin minute quantities using sensitive immunological,biochemical, and genetic techniques. (Seebox 3-C, pp. 108-109.) Telltale traces of DNAfrom virulent strains of bacteria and viruses mightbe discovered in samples collected during anonsite inspection of a suspect site, even after thefacility had undergone decontamination. Suchtraces might be indicative of previous research orproduction activities at the facility. Fermentersalso generate large quantities of liquid wastes thatmight contain unusual metabolic byproducts andother telltale chemicals even after decontaminationtreatment.Nevertheless, the fact that certain toxins andmicrobial pathogens have defensive or medicaluses means that it can be difficult to distinguishlegitimate from illicit BTW activities. Toxinsalso differ from chemical-warfare agents in thatthey do not leave persistent traces in the environmentand are easily destroyed by autoclaving withsuperheated steam. The extent to which heatneutralizedprotein toxins could be detected byimmunological methods is unknown. Finally, theability of modem analytical techniques to detecttrace amounts of biological organisms couldmake legitimate biotechnology facilities reluctantto submit to such intrusive inspection for fear oflosing proprietary information. Analytical instrumentscould probably be “blinded,” however, todetect only the presence or absence of knownBTW agents.BIOMARKERSSince the workforce in a BTW productionfacility would likely be immunized against theagents being produced, another approach toverification would be to determine whether theblood of workers in a suspect fermentation orvaccine facility contains antibodies against knownBTW agents. Monitoring of immunization programswould involve taking blood samples fromplant workers for onsite immunological analysis.Another approach would be to take blood samplesfrom wild animals (e.g., rodents) in the vicinity ofa suspect facility to detect possible exposure tounusual infectious agents.Although most vaccine production plants requireall workers to undergo initial and periodicblood collection and analysis, it would be difficultto negotiate a verification regime that requiressuch intrusive inspections. Furthermore, performingsuch tests as part of routine onsite inspectionsmight violate U.S. constitutional protectionsagainst “unreasonable searches and seizures,”since it would be difficult to protect confidentialmedical information unrelated to the purpose ofthe inspection. According to one legal scholar,“No treaty could empower inspectors to conductrandom intrusive body searches for possibletelltale evidence of radiation or biological weapons.“ 105 Another analyst argues, however, thatbiomedical sampling might be upheld by thecourts on grounds of national security if thereis a clear connection between the objectives ofthe regime and the analysis of biochemicalindicators. l06105 David A, Koplow, “Arms Control Inspection: Constitutional Restrictions on ‘IYeaty Verification in the United States,” New YorkUniversity Luw Review, vol. 66, May 1988, p. 355.1~ Jq R. S@ckto~ Edward A. Tanzman, and Barry Ke- Harmonizing the Chemical Weapons Convention With the Um”ted StatesConstitution (McLeq VA: BDM International, Report No. DNA-TR-91-216, April 1992), p. 59.

Chapter 3-Technical Aspects of Biological Weapon Proliferation 1107| Stockpile and Delivery System SignaturesStockpiling of agent or loading into sprayers,munitions, or other delivery systems might beassociated with a number of signatures. Thefollowing might be observable by aerial orsatellite photography:■■■cold storage of bulk BTW agents in refrigeratedbunkers or igloos, although small quantitiesof stored agent would probably not bedetected;storage depots for BTW-capable munitionsand delivery systems in proximity to possibleproduction facilities; andheavy trucks for the transport of empty orfilled munitions in the vicinity of a biologicalproduction facility.The remaining signatures could only be detectedduring an onsite inspection:inappropriate metal-working equipment orstock that might be used to fashion munitions;specialized equipment for filling BTW agentsinto munitions and warheads;breeding of insect vectors, or acquisition ofequipment for disseminating biological agentsand toxins as an aerosol cloud;munitions or parts thereof for disseminatingBTW agents; andthe training of troops in the tactical use ofBTW agents.| Weapon Use SignaturesBTW agents might either be used deliberatelyor escape accidentally from a secret militaryresearch or production facility, as happened in theSoviet city of Sverdlovsk. It is therefore importantto determine whether an outbreak of infectiousdisease in an area where it is not endemic isthe result of clandestine biological warfare activitiesand, if possible, to identify its source. Fieldepidemiology can help investigate alleged casesof biological and toxin warfare. 107 Indeed, theCenters for Disease Control’s Epidemic IntelligenceService was originally founded in 1951 outof concern that terrorists or foreign intelligenceagencies might launch a covert BTW attackagainst the United States. l08As a first step, all of the likely natural causes ofan epidemic must be investigated and excluded—a difficult task given the enormous variability ofinfectious diseases. Covert attacks aimed ateconomic sabotage are most likely to involveanimal or plant pathogens. The best known caseof a suspicious epidemic took place in 1981 inCuba, which suffered a severe outbreak of denguefever, a mosquito-borne viral illness. Of theestimated 350,000 people who developed thedisease, approximately 10,000 suffered fromsevere (hemorrhagic) symptoms and 158 died, amortality rate of 1.6 percent. l09 Cuban PresidentFidel Castro blamed the epidemic on covert U.S.biological warfare, which he alleged was beingrun by the Central Intelligence Agency. Epidemiologicalanalysis indicated, however, that theoutbreak was of natural origin. The Cubanepidemic occurred a few months after a majoroutbreak of hemorrhagic dengue fever in SoutheastAsia. Epidemiologists determined that Cubanconstruction workers building a hotel in Hanoi,Vietnam, had become infected with the disease.After returning home to Cuba, they were bitten byWI Peter B~s, “Epid~c Fie]d hvestigation as Applied to Allegations of Chemierd, Biological, or lbxhl W@ire, ” PO/itiCS andthe Lz~eSciences, vol. 11, No. 1, February 1992, pp. 5-22.1~ Stephen S. Morse, ‘‘Epidemiological Surveillance for Investigating Chemical or Biological Warfare and for Improving Human Heal@’ ‘Politics and the Life Sciences, vol. 11, No, 1, February 1992, pp. 28-29.1~ Jay P. Sanford, ‘‘Arbovirus Infections,’ Eugene Braunwald et al., Harrison ’s Principles oflnternal Medicine, 1 Ith ed. (New YoX NY:McGraw-Hill, 1987), p. 727.

108 I Technologies Underlying Weapons of Mass DestructionBox 3-C-Biochemical Detection of BTW AgentsInspections of microbioiogical laboratories or production facilities for indications of BTW activities mightinvolve the collection and analysis of samples to detect the presence of undeclared pathogens or toxins. Suchsamples might include wipes from equipment and air filters or liquid samples from the waste stream or theenvironment near the plant Alternatively, air filters might be used to screen large volumes of air inside, or evenat a considerable distance from, a plant.Immunological techniques. The fastest method for detecting pathogens is to use specic antibodies that havebeen Iabelled with a tag of some type, such as a fluorescent molecule or a radioactive atom. Such antibodies wouldbind to the pathogen with high specificity, providing nearly unambiguous evidence of its presence. Techniquesfor producing large quantities of “monocional” antibodies, all specific to a single marker protein on the surface ofa microorganism, permit the detection and identification of minute quantities of bacterial and viral agents (andprotein toxins) in Mood or environmental samples. Such immunological screening techniques includeradioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA). A drawback of such assays is thatthey could not identify BTW agents that had been genetically modified to alter their immunological characteristics.Bioassays. A pathogen or toxin can be detected by measuring its physiological effects on intact organismsor on isolated cell or enzyme systems. For example, many toxins work by specifically inhibiting the enzymeacetylcholinesterase involved in nerve transmission, thereby reducing its ability to break down the messengerchemical acetylcholine. Devices known as ‘biosensors” are under development that use receptor molecules orenzymes immobilized on the surface of a chip to detect the binding of toxins or viral agents. One biosensor capableof detecting toxins, developed by engineers at Arthur D. Little, is moving into a manufacturing prototype. 1Genetic analysis. The advent of recombinant-DNA techniques has made it possible to identify minusculequantities of microorganisms in complex samples.The first step is to prepare standards by isolating single-strandDNA sequences from specific microorganisms or synthesizing them chemically and labeling them with aradioactive isotope or a fluorescent dye. These labeled DNA fragments, known as “DNA probes,” can pair up or“hybridize” with DNA in a sample if the sample contains DNA from the same microorganism. The advantage ofDNA probes is their unique specificity, which enables them to identify a single type of pathogen even in complexmixtures.Because of background noise, it can be difficult to detect probe/target hybrids when only a small number ofmicroorganisms are present in the sample. This problem was solved in 19$5 with the development of a powerfulnew technique known as polymerase chain reaction (PCR), which can amplify a given DNA sequence as muchas 1O 8 times. PCR therefore makes it posssible to use DNA probes to identify pathogens present in tracequantities-as few as tensor hundreds of microorganisms-without having to grow them into larger colonies overa period of days or weeks. Since PCR reagents are available in kit form, this technique has greatly speeded thediagnosis of infectious diseases, including potential BW agents such as anthrax bacteria. 2 PCR is also useful foranalyzing biological samples in the field or during an onsite inspection of a suspect facility it has even detectedkilled bacteria in autoclaved samples?1 Ri~a~F.Tayl~,~h~D. IJttie Corp., Ciportabie, Real-ThneB iosensorsforChemicai AgentVerifioation,”presentation at the Chemical Wafxms Convention Vedfioation Teohnoiogy Researoh and DevelopmentConference, Herndon, VA, Mar. 2-3,1993.2 ~~~~ of ogf~~, A~~@ fkpcwf to CongraIss on the IWeamh, w-t ~- and ~-ju~t~onof ttm Chemloa~idogical LWWse Program * the Petfod October 1, 19$0 77nwgh Septemher 30, 7991,RCS:DD-USDRE(A) 1085, p. 51. See also, M. Carl et al., CIDeteotlon of spores of Bad#us anthrads using thepolymerase chain reaotion;’ Journa/of/nib@ous IXseas~ voi. 185, 1992, pp. 1145-1148.3 T. ~rry and F. (3annon, W)irgot C3enomio DNA Arnpiifkation From Autooiaved Infeotlws -OOrgankrnsUsing PCR T~hnology,” PCR A4ethoo% and A#oatAww, VOL 1,1991, p. 75.

Chapter 3-Technical Aspects of Biological Weapon Proliferation I 109Nevertheless, PCR has some limitations. First, it is only suitable for identifying known organisms, since onemust decide in advance which DNA sequences to use as probes. Second, because many pathogenic microbes(e.g., anthrax bacteria) are ubiquitous in the environment in trace amounts, a probe of sufficient sensitivity mayfind “prohibited” DNA everywhere! Third, the accuracy of PCR depends on both the length of the target DNAsequence and the length of the PCR “primers,” which bind to the target DNA to initiate the amplification process.As one tests for shorter sequences (e.g., 100 instead of 1,000 DNA base-pairs), the sensitivity of the techniqueincreases but its specificity declines, since several different microbial species may have identical short DNAsequences. For this reason, two levels of detection have been proposed, depending on the characteristics of theDNA probe. The first level would identify the group of pathogenic bacteria to which a suspect agent belongs bydetecting a DNA sequence common to all species in that group; the second level would provide species-specificidentification by using longer DNA probes specific to each microorganism targeted for detection. 5Genetic fingerprinting. Known technically as restriction-fragment length polymorphism (RFLP) analysis, thistechnique involves the use of special “restriction” enzymes that cut microbial DNA at specific sites. This treatmentresults in a pattern of DNA fragments of different sizes, which can be analyzed by separating the fragments ona gel. Genetic fingerprinting can also be done with RNA viruses. The result of this technique is a characteristicpattern of spots on the gel. Since different DNA sequences will result in a different pattern of spots, comparingsuch maps will reveal the extent to which two strains of a bacterium or virus differ genetically.All microbial pathogens can be “fingerprinted” by analyzing their genetic material (DNA or RNA). Since thereare always minor genetic differences among various strains of a pathogenic microorganism, it is very likely thata laboratory-developed strain is genetically distinct from an indigenous strain. Moreover, an indigenous strain thathas been produced in large quantities is likely to be more genetically homogeneous than the causative agent ofa natural epidemic. For many microbial pathogens, scientists have compiled a library of characterized strains t hatcan be compared with any newly discovered strain. Thus, genetic fingerprinting often provides enough informationto determine the source of a virus and whether it has been modified genetically in the laboratory. Trace amountsof genetic material can be amplified for further analysis using PCR.Town analysis. For toxins, analytical techniques for detection and characterization include immunoassay, aswell as analytical chemistry techniques such as combined gas chromatography/mass spectrometry (GC/MS),liquid chromatography, and others. Quadruple mass spectrometry is used to analyze protein toxins, as well assamples dissolved in water. 6 Very large biomolecules must be broken down into smaller components for analysis.To this end, a technique known as pyrolysis mass spectrometry involves heating complex materials in a controlledmanner to generate characteristic chemical signatures that can then be analyzed by a mass spectrometer. 7 Thesesignatures are compared with a large computer database of known chemical spectra to identify the compoundspresent Finally, if a pure sample of a protein toxin or peptide bioregulator is available, it may also be possible toidentify it from its amino-acid sequence. Off-site detection of toxins is nearly impossible, however, because theylack volatility.4 Moreover, a laboratory might detect a contaminant from past rather than current WO*, SUM as anthraxspores from earlier samples.5 BarbaraJ. Mann, De@cfjono~Bb/o@a/ WarfareAgenfs Ush?gl the Po/ymerase Chah? l?eacfion (ResearchTriangle Park NC: Battelle Memorial Institute, September 1992), DTIC No. AD-A259391.6 External Affajrs and International Trade Can-Verification Research Unit, V&lf&NIOn: De@opmnf ofa Porfab/e Trichothecene SensorK7f fortf?e Defecfkm of T-2 f@cofox/n In Human B/oodSampfes (Ottawa: ExternalAffairs, March 1987).7 Diane M. Kotras, “New Detection Approaches for Chemical and Biological Defense,” ArmY Resear@,Development and~cquisltion Bu//etin, January-February 1989, p. 2.

110 | Technologies Underlying Weapons of Mass Destructionmosquitoes, which then transmitted the disease toothers. 110Another suspicious epidemic that still remainsto be explained took place during the civil war inRhodesia (now Zimbabwe) from 1978 to 1980.An unprecedented outbreak of cattle anthrax wasalmost entirely confined to the Tribal TrustLands-the areas then assigned to Rhodesia’sblacks and accounting for about 17 percent of thecountry’s land area.111 Since cattle were theprimary source of wealth for black farmers, theepidemic — led to the severe impoverishment of theected rural populations. The outbreak of cattlethrax was accompanied by a secondary humanidemic, which resulted in more than 10,000infections and 182 human deaths. Since anthrax isnot contagious from one individual to another, theexplosive nature of the human epidemic wasstriking: the reported incidence of human anthraxcases during the 1979-80 period was more than400 times the average incidence of the previous29 years. Some epidemiologists believe that thelosing Rhodesian government forces may haveresorted to biological warfare with anthrax againstcattle in order to impoverish the rural blackpopulation, as a desperate tactic in the finalmonths of the civil war, and that humans wereinfected secondary to contact with infected animalsor animal products. 112EPIDEMIOLOGICAL ANALYSISDistinguishing natural disease outbreaks fromthose produced deliberately requires careful investigationand knowledge of local diseases andendemic infections. There is at present no generallyaccepted methodology for investigating thepossible use of BTW agents. But Dr. JackWoodall, an epidemiologist with the WorldHealth Organization in Geneva, has identified anumber of characteristics of a disease outbreakwould suggest it was not of natural origin: 113The appearance of an endemic disease faroutside its established range. A naturaldisease outbreak might be distinguishedfrom a BTW attack by determiningg whetherits source is an agent endemic to the region.Although jet travel has made it easier forinfectious agents to spread discontinuouslyfrom one continent to another, the progressionof an epidemic typically involves gradualspread to contiguous regions or alongtransportation routes.Appearance of a vector-borne disease in theabsence of natural vectors or reservoirhosts. Plague epidemics, for example, typicallybegin in rats and are spread to man byinfected fleas. The initial form of the diseasein humans is the bubonic form affecting thelymph nodes, which later converts into themore lethal and contagious pneumonic form.Thus, the sudden appearance of pneumonicplague in humans (1) in the absence ofinfected rats and fleas, and (2) withoutprecursor cases of the bubonic form, wouldbe suggestive of a covert BW attack.Pulmonary disease in the absence of naturalmechanisms for producing high-concentrationbiological aerosols. Since many infectiousdiseases do not naturally infect thelungs, the anomalous appearance of a respi-110 q+leph~~e ~tmiew +~ Dy, sc~~ ~te~, ~soci~e Dir@or of tie H~th Scien@s Divisio~ Rockefeller Fourl&itiou New yOr~NY, Aug. 6, 1992.111 See J.C.A. Davies, “A Major Epidemic of Anthrax in Zimbabwe, Part l,” Central Afi”can Journal of Medicine, vol. 28, 1982, pp.291-298; and J.C.A. Davies, “A Major Epidemic of Anthrax in Zimbabwe, Part 2,” Central Afi”can Journal of Medicine, vol. 29, 1983, pp.8-12.112 M~lN=, ~ c~~Epimoticin~~~e, 1978-1980: ~etoDeh~mte Spr~d?’ The PSR Q@er/y, vol. 2, No.4, December 1992,pp. 198-209.113 Job p. w-, ~ ‘WO 1{~~ ~d Epidemic ~o~tion M a &MiS for v~~tion Activities Under the Biological W~IISConvention” S.J. Lundin, cd., Vievvs on Possible Verlj7cation Measures for the Biological Weapons Convention, SIPRI Chemical & BiologicalWarfare Studies No. 12 (Oxford, England: Oxford University Press, 1991), pp. 59-70.

Chapter 3-Technical Aspects of Biological Weapon Proliferation111ratory form of such a disease might beindicative of a deliberate aerosol attack.Other human activities than deliberate militaryattack may generate infectious aerosols,however. The outbreak of Legionnaires’ Diseaseat a hotel in Philadelphia, for example,was traced to a natural microbial contaminationof the building’s air-conditioning system.Unusual epidemiological patterns that differfrom natural disease outbreaks. A deliberateBW attack by aerosol dissemination wouldinfect a large number of exposed individualssimultaneously, causing a majority of themto develop symptoms at approximately thesame time. Thus, instead of a gradual risefrom a smaller number of precursor cases,there would be an “explosive’ outbreak ofdisease in many thousands of people. 114While these characteristics are all plausible, therecent natural outbreak in New Mexico of ‘ ‘Navajoflu, ’ a virulent respiratory illness withgreater than 30 percent mortality, meets nearly allof the criteria Woodall proposes. Hanta virus,now known to be the cause of the illness, hadnever before been known to occur among humansin the Western Hemisphere, Whereas all previousreported cases around the world were hemorrhagicfevers with shock and kidney failure, thisrecent outbreak took the form of a respiratoryillness. Finally, the epidemiology of the diseasewas extremely unusual and confused investigatorsfor months. This episode points out thedifficulty of distinguishing a highly anomalousdisease outbreak of natural origin from thedeliberate or accidental release of biologicalwarfareagents. 115An important task of epidemiological analysisis to characterize the strains of diseasecausingagents indigenous to the affected area,thereby making it possible to distinguish preexisting“background” strains from BW agentsintroduced from the outside. Even if it could beascertained that a disease outbreak was of artificialorigin, however, it might still not be clearwho had initiated the attack. It might also bedifficult to collect the necessary data if investigatorswere denied permission to visit the sites fY ;* i t.the alleged attacks.tA current problem with depending on epide&ology to detect the use of BTW agents is that suchskills are unlikely to be available in those regionsof the world where biological warfare is mostlikely. In order to detect new infectious diseasessuch as AIDS before they reach epidemic proportions,the epidemiologist Donald A. Hendersonhas proposed the establishment of an internationalnetwork of research centers to monitor theemergence and spread of new infectious diseases,linked to a global rapid-response system. ll6Beyond its obvious public-health benefits, such aglobal surveillance system would make it easierto distinguish artificially induced epidemics associatedwith the covert use of BTW agents fromordinary background noise. ‘‘117 It would therebyhelp to deter biological warfare and also to identifyfalse claims of BW, an important objective.Table 3-2 summarizes the various potentialsignatures associated with BTW development,114 Nevefieless, tie anthrax epdtmic in the Soviet town of Sverdlovsk (now Yekaterinburg) in 1979-now recogniz.ed to have ~ntheredtof an accidental release of anthrax spores from a Soviet military biological facility-was associated with a gradual increase in the number ofcases over a period of several weeks, a pattern that appeared consistent with a natural epidemic. It is lmo~ however, that at low levels ofexposure, anthrax spores ge rminate at different rates in exposed primate hosts, resulting in highly variable incubation periods. MatthewMeselso~ Harvard University, personal communication 1993.I Is m~coff, 0p. cit., footnote 29.1ls Donald A. Henderson, “Surveillance Systems and Intergovernmental Cooperation” Stephen S. Morse, cd., Emerging Viruses (NewYork: Oxford University Press, 1992), pp. 283-289. See also Joshua Lederberg et al., Emerging Infections: Microbial Threats to Health in theUnited States (Washingto~ DC: National Academy Press, 1992), pp. 134-137.1‘7 Mark L. Wheelis, “Strengthening Biological Weapons Control Through Global Epidemiologicat Surveillance, ” Politics and the LfeSciences, vol. 11, No. 2, August 1992, pp. 179-189.

112 I Technologies Underlying Weapons of Mass DestructionTable 3-2—Biological Weapon Program Signatures and ConcealmentProgram stage Signature Detection methods (examples) Concealment methods, commentResearch &-.Scientific and technical publicationsLiterature survey and analysis. . . . . .1. Manage publication activitiesdevelopment(presence or absence)2. Use widely available technicalinformation rather than designnew agents or techniquesNondeclaration of work withpotential BTW agents or withpathogen aerosolsHuman intelligenoe (humint),on-site inspectionsConceal undeclared activitiesClandestineproduction plantSecurity measuresLarge numbers of eggs orlaboratory animals for virusproductionStorage depots for BTWcapablemunitionsOverhead imaging or humintHumintOverhead imaging or humintConceal measures, or place plantwithin other secure facilitiesUse tissue culture rather thananimals for production of virusesConceal depots underground(although faciiity building wouldbe visible)imports of dual-use equipment(fermenters, lyophilizers, microencaipsulationsystems)Tracking of exports tosuspected proliferants1. Obtain equipment from multiplesuppliers, or through intermediaries2. Divert equipment from legitimatecivil activities3. Make equipment indigenouslyConverted ormultipurposepharmaceuticalplantSecurity measures Overhead imaging or humint Conceal measuresResidues of virulent microbialstrains or genetically modifiedagentsSpecial safety and containmentmeasuresProcesses or capacity that cannotbe justified on technical oreconomic groundsSampling of air, water, or soil inor near suspect plants; togetherwith various forms of biochemicalanalysis (e.g., ELISA, bioassay,DNA probes, PCR)Onsite inspection of suspectplantsOnsite inspection of suspectplants1. Decontaminate production linewlth bleach or superheated steamand autoclave cultures2. Remove wastes for off-sitedisposal3. Claim that BTW agents arebeing used for defensive activities1. Sacrifice worker safety2. Modern biotech plants increasinglyhave these featuresSuch assessments are highly subjectiveSeed stocks, cell lines, andequipment (e.g., microencapsulation)inappropriate fordeclared activitiesOmission of costly measuresto ensure purity and sterilityof pharmaceuticals or toinactivate agent to makevaccineFacilities for rapid, large-scaledecontaminationOnsite inspection and samplingOnsite inspectionOnsite inspectionClaim that material and equipmentis being used for legitimate medicalapplications, although possibilitiesmay be limitedEmploy measures to simulate pharmaceuticalproduction (costly)Use legitimate vaccine productionactivities as a cover

Chapter 3-Technical Aspects of Biological Weapon Proliferation 113Program stage Signature Detection methods (examples) Concealment methods, commentWeaponization andtestingEvidence of immunization toBTW agents in plant workersor evidence of infection in peopleor animals nearbyUniquely configured arsenals(e.g. distribution of storagebunkers)Cold storage of BTW agentsSpecialized equipment forfilling agents into munitionsBTW testing facilities, suchas small aerosol chambersField testing of aerosolgenerators and delivery systemsLarge animals for aerosol testingField training of troopsUniquely configured test facilitiesBlind testsOverhead imagingThermal infrared imageryExcess electrical capacit yOnsite inspectionOnsite inspection, samplingand analysisOverhead imaging, onsiteinspection, sampling andanalysisOverhead imagingRefuse permission to take bloodsampilsPattern facilities after conventionalarsenals1. Produce large quantities of agentshortly before use to minimizeneed for storage2. Mask thermal-infrared emissionsfrom refrigeratorsConceal filling operation at someremote locationCarry out tests inside dosedbuildings1. Mask test grid2. Use legitimate activity such asbiopesticide dissemination as acover for illicit activities, althoughhigh security might be a giveaway1. Make special features temporary2. Test on overcast days, at night,or in absence of overhead imagingsystemsWeapon useAnomalous characteristics of adisease outbreak (e.g., atypicalagent, explosive diseasespread, pulmonary disease inabsence of natural respiratory1. Field epidemiology2. Genetic fingerprinting ofdisease agentUse a disease agent indigenous tothe area being attackedSOURCE: Office of Technology Assessment, 1993.production, weaponization, and use. Many ofthese indicators are nonspecific, since their presencecould be associated with other, legitimateactivities. Even so, a pattern of such signatureswould be suggestive of a clandestine BTW programthat could then be confirmed by other means.MILITARY IMPLICATIONS OF GENETICENGINEERINGThe past two decades have seen revolutionaryadvances in the ability to manipulate the geneticcharacteristics of living organisms at the molecu-lar level. Genetic engineering involves identifyingregions along the DNA molecules that encodedesirable genetic characteristics and cutting andsplicing these segments of DNA with enzymetools to create “recombinant” strains. Since allliving creatures contain DNA, it is also possibleto combine genes across species lines to give anorganism novel traits that do not occur in nature.| Novel Agents?Techniques for the engineering of genes inbacteria and animal cells, and for the modification

114 I Technologies Underlying Weapons of Mass Destructionof proteins, have become widely available. Althoughadvanced genetic-engineering capabilitiesare still rare in the developing world, genesplicing“kits” containing the necessary equipmentand reagents (e.g., restriction enzymes) canbe easily obtained by mail order, and much of thenecessary know-how is openly published in thescientific literature. Some analysts have speculatedthat gene-splicing technologies could beused to develop ‘second-generation’ BW agentswith greater military utility by making the behaviorof these agents in the environment morepredictable. 118 Toxin genes and Virulence factorsmight also be transferred from one species ofmicroorganism to another. According to JohnBirkner, a foreign technology analyst for theDefense Intelligence Agency, “recombinant-DNA techniques could open up a large number ofpossibilities. Normally harmless, nondiseaseproducingorganisms could be modified to becomehighly toxic and produce effects for whichan opponent has no known treatment. Otheragents, now considered too unstable for storage orbiological warfare applications, could be changedsufficiently to become effective. ’ ’ 119Although it could theoretically add a toxingene to a harmless bacterium to render it virulent,recombinant-DNA technology is unlikely to producenovel pathogens more devastating than thehighly infective and lethal agents that alreadyexist in nature. The reason is that any attempt tocombine genes from unrelated organisms is likelyto interfere with the highly developed and integratedpattern of genetic traits that give rise topathogenic behavior. Since a whole constellationof genes must work together for a microorganismto cause disease, altering a few genes withrecombinant-DNA techniques is unlikely to yieldthata novel pathogen significantly more deadly thannatural disease agents. 120 It is therefore doubtfulgenetic engineering could result in novelBW agents with greater potency than naturallyoccurring agents.| Increased Controllability of MicrobialAgentsNevertheless, the genetic modification of standardBTW agents might, however, overcomespecific obstacles that currently limit their militaryutility. In particular, genetic engineering andmodern biotechnologies can facilitate microbialproduction, improve storage and delivery, createantibiotic resistance, and enhance the controllabilityof existing pathogens. It is not clear, however,that these modifications would significantlyalter the military utility of BW agents comparedwith the numerous already known agents.SHORTER INCUBATION TIMEModifying BW agents to act more rapidlywould increase their tactical utility on the battlefield,although this is unlikely to be accomplishedanytime soon.ENVIRONMENTAL STABILITYGenetic engineering might be able to increasethe ability of microorganisms and toxins towithstand some of the stresses associated withstorage and dissemination, for example, by insertingcomplexes of genes for resistance to inactivationby temperature, ultraviolet radiation, drying,and the shear forces associated with aerosolformation. Most of these traits are geneticallycomplex, however, and are not well understood.INCREASED VIRULENCEDevelopment of a system for the superexpressionof toxin genes has made it possible todevelop recombinant bacterial strains that pro-118 fi~d Geisslm, “~plica~o~ of @netic I@ina@ for Chemical and Biological Wti~,” W~r/dAr~~nt.S and Disannanent:SZPRI Yearbook 1984 (lmdon: lhylor & Francis, 1984), pp. 421451.119 Job BhkXICX, cit~ in R. J&ffey %n.i~ “The Dark Side of Biotechnology,” Science, vol. 224, June 15, 1984, p. 1215.In Jom~ B. ~cker, ‘‘Gme: WarS, ” Foreign Policy, No. 57, winter 1984-85, p. 62.

— . . -.Chapter 3–Technical Aspects of Biological Weapon Proliferation I 115duce 10 tostrains.100 times more toxin than naturalANTIBIOTIC RESISTANCEInserting antibiotic-resistance genes into naturallyinfectious agents can make them resistant toone or more prophylactic or therapeutic drugs,rendering such defenses useless. At the sametime, an attacker could immunize his troopsagainst the modified agent, protecting themwithout the need for antibiotics. Reportedly, theSoviet Union launched a secret program in 1984to develop a genetically engineered form ofplague that was resistant to antibiotics. 121VACCINE PRODUCTIONRecombinant-DNA techniques make it easierand safer to produce specific vaccines to matchnovel agents, thus enabling the attacker to protecthis own forces while denying a vaccine to thedefender. In the past, the difficulty of producingeffective protective vaccines was a major obstacleto acquiring an offensive BTW capability. Nevertheless,recombinant vaccines are not alwayseffective because they represent one or a fewantigens rather than the full set of antigens presentin the actual pathogen.CONTROLLED PERSISTENCEGenetic engineering might result in morecontrollable BW agents through the manipulationof genes to program the survival of a bacterialpopulation released into the environment. Forexample, it might be possible to program microorganismsgenetically to survive only under anarrow set of environmental conditions. Alternatively,one might design regulatory sequencesknown as ‘‘conditional suicide genes, ’ whichcause a microorganism to die off after a specifiednumber of cell divisions. 122 By inserting such genesinto pathogens, it might be possible to create aBW agent that would cause disease for a limitedperiod of time and then spontaneously die off.IMMUNOLOGICAL MODIFICATIONBy means of gene transfers, it would bepossible to modify the antigenic (antibodyinducing)proteins on the outer surface of apathogenic virus or toxin, thereby rendering themodified agents insensitive to a preexisting hostimmunity or to standard vaccines and antitoxins.(Since most toxin antigens are located on thescaffolding of the molecule rather than near thesite responsible for its toxic effects, it would bepossible to alter the immunological characteristicsof a toxin without changing its biologicalactivity.) Further, since most diagnostic proceduresfor BTW agents rely on the detection ofcertain surface antigens with antibodies, modiflcationof the antigens would make it harder todetect, identify, and counter the modified agents.HOST SPECIFICITYSome analysts have raised the grotesque possibilityof making microbial pathogens more discriminateby designing ‘‘ethnic weapons’ thatexploit differences in gene frequency betweenpopulations to selectively incapacitate or kill aselected ‘‘enemy’ population to a greater extentthan a‘‘&iendly’ population. Yet human populationsare not uniform enough to be uniquelytargeted by a given pathogen. 123***These possibilities notwithstanding, the practicalobstacles to developing more controllable BWagents remain enormous. Even if genetic engineeringcould produce recombinant pathogensthat survived for a predetermined length of,%”121 Bw, op. cit., foo~ote 97! p- 41”122 ~qmatow Cohttee for tie ~rd Review Conference of the Parties to the BWC, Background Document on NW Scientific andTechnological Developments Relevant to the Convenh”on on the Prohibition of the Development, Production andstockpiling ofBacteriological(Biological) and Toxin Weapons and on Their Destruction, Document No. BWC/CONF.HI/4, Aug. 26, 1S91, p. 11.In Novick and Shul~ op. cit., footnote 47, p. 114.

116 I Technologies Underlying Weapons of Mass Destructiontime in the environment, they would remainincalculable in their effects, since their disseminationwould still rely on wind and weather,and mutations might change the behavior of agenetically modified agent after it had beenreleased. Once released,, living pathogens mightpropagate, evolve, and develop ecological relationshipswith other living things in ways thatcannot be entirely foreseen. Furthermore, geneticallyengineered pathogens would require extensivetrials to verify that they would survive longenough to infect target personnel after beingdisseminated by a weapon system and exposed tothe natural environment, in which most microorganismsare extremely fragile. Thus, testing inhuman subjects might be required to give amilitary planner confidence in genetically engineeredbiological agents.| Modified Toxins and BioregulatorsAnother potential threat from the biotechnologicalrevolution is the development of newtoxin-warfare agents. Known protein toxins, suchas botulina1 and ricin, deteriorate in response toenvironmental factors such as temperature andultraviolet radiation, and thus rapidly lose toxicityafter dissemination. Although genetic engineeringis unlikely to increase the potency ofnaturally available toxins, it might conceivablybe applied to modify the chemical structure oftoxins to:● increase the stability of toxins so that theycan better be disseminated as an aerosol;■ alter the antigenic structure of toxin molecules,rendering them insusceptible to existingantitoxins or antibody-based diagnostictechniques;develop “chimaeric” toxins (combinationsof two different toxin molecules, such asricin and diphtheria toxin) that are morecapable of penetrating and killing targetcells; anddesign novel peptide toxins (possibly — consistingonly of the biologically active regionof a protein toxin) that are as poisonous asnerve agents but are small enough to penetratethe filters currently used in masks andprotective garments. l24BIOREGULATORSRecombinant-DNA research may also lead tothe development of more effective incapacitants.With genetic engineering, even the body’s ownnatural substances might be utilized as warfareagents. “Bioregulators’ are small, physiologicallyactive peptides (chains of amino acidssmaller than proteins) that are normally present inthe body in minute quantities and that orchestratekey physiological and psychological processes.They are active at very low concentrations andinfluence the full spectrum of life processes, bothphysiological and mental. Bioregulators govern,for example, hormone release, control of bodytemperature, sleep, mood, consciousness, andemotions. An important subgroup of the bioregulatorsare the opioid peptides, which can induceanalgesia and euphoria. Since these naturallyoccurring peptides are active in the body in traceamounts, the application of larger quantitiesmight induce euphoria, fear, fatigue, paralysis,hallucinations, or depression, giving them somepotential as nonlethal incapacitating weapons. l25Bioregulators might be modified chemically toenhance their physiological activity, stability, orspecificity. For example, the modification of thepeptide hormone LHRH (leutenizing hormone124 fite~ ~fis ~d ~tematio~ T~de CaMda, VtiWtionReWh Unit, Novel Toxins and Bioregulators: The Emerging Scientificand Technological Issues Relating to Verification of the Biological and Tom-n Weapons Convention (Ottawa: External Affairs, September1991), p. 47.12S Sw~shNatiO~ ~eme ;Resemch~ti~te, &nefiCEnginee~”ng u~DiOJOgiCuz weupo~, @)ortNo. PB88-210869 ~m~, SwdemNational Defense Research Institute, November 1987; translated for the Office of International Affairs, National THmieal Information Semice,h’ftIy 1988), p. 58.

Chapter 3-Technical Aspects of Biological Weapon Proliferation I 117Table 3-3—implications of Genetic Engineering for Biological and Toxin WarfareCapability Possible now May be possible May be possibleIn 5 yearsIn 10 years, If everShorter incubation timeTemperature stabilityUV stabilityDrying/aeosol stabilityAntibiotic resistanceControlled persistenceImmunological modificationHost specificityCloning of toxin genesMore stable toxinsNovel toxinsa For ~rtain Protein toxinsbFor bacteriaC In some cases, not allSOURCE: Office of Technology Assessment, 1993.XaXcx cxxXbxxxxxreleasing hormone) by substituting a single aminoacid yielded a product 50 times more potent. 126Even so, it would be difficult to disseminatepeptides through the air in a militarily effectiveway. The ability of a peptide to diffuse across themucosa1 membranes of the respiratory tract dependson its molecular size. Although attempts todeliver the small peptide hormone ADH (antidiuretichormone) with a nasal aerosol have beensuccessful, similar efforts with insulin have failedbecause of the molecule’s relatively large size. 127The possible implications of genetic engineeringfor biological and toxin warfare are summarizedin table 3-3. Although the potential for themisuse of genetic engineering to develop new andmilitarily more effective BTW agents currentlyappears limited, this emerging threat clearlydeserves to be monitored carefully. Advancedgenetic-engineering capabilities are still rare inthe developing world, but most of the largercountries in the Middle East already have thetechnical capability to selectively breed microbialstrains with enhanced virulence, survivability,and antibiotic resistance. In According to oneanalyst, “If you can identify the gene you want tomove, it is possible to do so. ’ 129For at least the medium-term, BTW proliferantsare likely to produce proven agents suchas anthrax and botulin toxin, rather thaninvest large amounts of time and money onexperimentation with genetically engineeredmicroorganisms. Eventually, however, technologicallysophisticated proliferants might tryto modify standard agents to make them morestable during dissemination or more difficultto detect or to defend against.lx Gove~ent of tie United States, op. cit., footnote 44, p. 29.127 Zficoff, Op. cit., footnote 29.12E ~~ony H. Cordesu weapons of ~a~~ De~~ctiOn in r~e ~~/e East @ndOn: BrzI.ssey’s ~), 1991), p. 77.In ~~cot=f, Op. cit., foomote 29.

TechnicalAspectsofNuclearProliferation 4Awide variety of policy tools are available for combatingnuclear proliferation, as described in the OTA ReportProliferation of Weapons of Mass Destruction: Assessingthe Risks. l Since these measures depend at least inpart on the technical prospects for monitoring and controllingnuclear proliferation, this chapter provides background on thedifficulty and the detectability of nuclear weapon production. Itdescribes the technical requirements for developing a nuclearweapon, identifying the steps that are the most difficult,time-consuming, or expensive, as well as those that are mostamenable to external control. It also discusses detectable‘‘signatures’ associated with each of these steps that might beused for monitoring or verification purposes.To evaluate the proliferation risks posed by any particularcountry, however, or to determine which policies can mosteffectively reduce those risks, the technical hurdles describedin general terms in this chapter must be considered in thecontext of the country’s individual situation. In many cases,nontechnical considerations, rather than technical ones, maydominate not only whether a country decides to pursue nuclearweapons but also its likely success in doing so. These factors,which are highly country-dependent, include:the ability of a government to organize, manage, and carrythrough complex, long-term projects involving a largescientific and technological infrastructure, and to keep statesecrets;a country’s foreign business contacts, trade, and supply ofhard currency; and1 U.S. Congress, C)fflce of ‘Rxhnology ~sessmen~ Proliferation of Weapons ofMass Destruction: Assessing the Risks, O’lX-ISC-559 (Washingto~ DC: U.S. GovernmentPrinting Office, August 1993).I 119

120 I Technologies Underlying Weapons of Mass DestructionFigure 4-l—Technical Routes to a Nuclear Weapon CapabilityUranium route—Enrich uranium–—-—+ to weapongradeFabricatehighly enriched> uranium intobomb core—TNatural uraniummining andprocessingr●3Plutonium route-—-->”Irradiate uraniumwithin reactorto generate LplutoniumReprocess toFabricateobtain pure + plutonium into I—>12m-_ll-2!zlI___TDesign/fabricatehigh explosive(HE) componentsor propellants3----------’Acquire or design/ ?Weapon assemblyDelivery vehicleR&D (aircraft,missile, or other)+LPurchase/steal/obtain weaponusablenuclear material‘-’w–-SOURCE: Office of Technology Assessment, 1993.Weaponcapability■ the domestic and international costs of gettingcaught, including possible diplomaticisolation and potential loss of trade, oftechnology transfer, or of foreign assistance.Addressing such technical and nontechnical factorson a country-by-country basis, however, isbeyond the scope of this report.OVERVIEW AND FINDINGSManufacturing nuclear weapons, shown schematicallyin figure 4-1, is a complex and difficultprocess. It can be divided into three basic stages.The first, and most difficult, is the productionof the special nuclear materials-plutonium,uranium-233, or enriched uranium-235—thatare at the heart of a nuclear warhead. Thesematerials can sustain nuclear chain reactions thatrelease tremendous amounts of energy in a shortperiod of time (see box 4-A for definitions ofvarious nuclear materials). To manufacture highlyenriched uranium-235 (HEU) for weapons, theuranium-235 isotope must be separated from themuch more common uranium-238. A number oftechniques can be used to enrich uranium, all ofwhich to date involve complex and expensivefacilities (see app. 4-B on enrichment technologies).Plutonium for weapons is derived from thenaturally occurring uranium-238 isotope, whichcannot be used directly in a nuclear weapon.However, irradiating uranium-238 in a nuclearreactor will convert part of it into plutonium-239,which can be used in nuclear weapons after it isseparated from the unconverted uranium andother irradiation byproducts in a step calledchemical reprocessing. Similarly, uranium-233 is

Chapter 4-Technical Aspects of Nuclear Proliferation I 121Box 4-A-Glossary of Nuclear MaterialsFertile material-an isotope that can be transformed into a fissile isotope by absorbing a neutron, such as whenirradiated in a nuclear reactor. For instance, U-238 is a fertile (as well as fissionable, see below) materialthat tends to absorb slow neutrons, after which it decays into the fissile isotope Pu-239. Thorium-232 cansimilarly be transformed into U-233.Fissile material-an isotope that readily undergoes fission (splits into two or more lighter elements, therebyreleasing energy) after absorbing neutrons of any energy. Fissile materials can undergo self-sustainingnuclear chain reactions, in which the neutrons released in fission reactions will themselves induce additionalfission reactions (most fissile materials emit two or more additional neutrons, on average, per fission).Important fissile isotopes are U- 233, U-235 and Pu-239. (Pu-241 is also fissile, but is normally created asa byproduct of Pu-239 production.)Fissionable materitial isotope that undergoes fission only after absorbing neutrons above a certain energy. Themost important fissionable material, U-238, emits less than one additional neutron, on average, per fissionreaction; thus, although it can release additional energy when bombarded by neutrons of sufficient energy,it cannot sustain a nuclear chain reaction.Highly enriched uranium (HEU)-uranium enriched in the isotope U-235 to 20 percent or more; often refers toenrichments above 80 percent, which are more useful for nuclear weapons. Uranium enriched to such levelswill normally contain about 1 percent U-234, which is responsible for much of its radioactivity.Low-enriched uranium (LEU)-uranium enriched in the isotope U-235 to less than 20 percent; often refers toenrichments of 2 to 5 percent, which are used to fuel t he most common type of commercial power nuclearreactor (“light-water reactors”).Mixed oxide fuel (MOX)-nuclear reactor fuel composed of plutonium and natural or low-enriched uranium in oxideform (U0 2and PuO 2. The plutonium component plays the role of the fissile U-235 isotope in LEU fuel, thusreducing the need for uranium enrichment. For instance, MOX fuel with a plutonium concentration of about3 to 5 percent can substitute for a portion of the low- enriched uranium fuel in most types of nuclear reactor.(LEU-fueled reactors also make and burn plutonium as they operate, such that by the time LEU fuel isconsidered to be “used up,” it contains more plutonium than U-235.)Natural uranium (Nat-U)-uranium of the isotopic concentration occurring in nature, in which about 0.7 percentis the isotope U-235, and 99.3 percent is U- 238. It also contains a trace of U-234.Reactor-grade plutonium (RGPu)-plutonium that contains at least 20 percent of the nonfissile isotopes Pu-240and Pu-242. RGPu is produced in most power reactors under normal operation, whereby fuel elementscontaining U-238 are exposed in the reactor to high neutron fluences for long periods of time (typically ayear to a few years).Weapon-grade plutonium (WGPu)-plutonium that typically contains 6 percent or less of the isotopes Pu-240 andPu-242, isotopes that makes design of nuclear weapons increasingly more difficult. WGPU is created whenU-238 is irradiated in a nuclear reactor for only a short period of time.Yellowcake-uranium concentrate (with the isotopic ratio of natural uranium), which is produced from uranium orethrough a process called “milling”; consists of about 80 percent U 3O 8; may also refer to U 3O 8itself.SOURCE: Office of Technology Assessment, 1993.

122 I Technologies Underlying Weapons of Mass DestructionThe Vienna International Center, housing the headquartersof the International Atomic Energy Agency.produced by irradiating thorium in reactors (thispath is not shown in figure 4-l). Neither theproduction of uranium-233 nor of plutoniumrequires enriched uranium.To make the enriched uranium or plutoniuminto a weapon, various additional componentsmust be added: chemical explosives (or in thecase of gun-type weapons, propellants) to assemblethe nuclear material into a super-critical massthat will sustain an explosive chain reaction;nonfissile materials to reflect neutrons and tampthe explosion; electronics to trigger the explosives;a neutron generator to start the nucleardetonation at an appropriate time; and associatedcommand, control, and security circuitry (see app.4-A on nuclear weapon design). In general,nuclear testing that involves a detonation ofthe resulting nuclear explosive device is notnecessary for a competent designer to havehigh confidence that a relatively unsophisticatedfission weapon will detonate, althoughnonnuclear testing of the chemical explosivesystem in an implosion-type weapon would berequired. A gun-type weapon made with HEUwould not even require chemical-explosivetesting. Nevertheless, nuclear explosive testingwould be much more important for a proliferantseeking to develop either very low-weightweapons, such as for delivery by missiles oflimited payload, or thermonuclear weapons.The third stage in developing a nuclear weaponcapability is integrating the weapon with adelivery system and preparing for its use. Many ofthe states seeking nuclear weapons also seem tobe developing ballistic missiles, and all alreadyhave combat aircraft. However, high-tech militarysystems are not required to deliver nuclearweapons; other military or civilian vehicles couldalso be used.| International ControlsIAEA SAFEGUARDSInternational efforts to control proliferationhave traditionally focused on production ofnuclear weapon materials, since that is themost difficult and the most visible (short ofnuclear testing) of the processes necessary tomake nuclear weapons. The Nuclear NonproliferationTreaty of 1968 (NPT) requiresnon-nuclear-weapon member states to place alltheir nuclear materials under safeguards: a systemof materials accountancy, containment, andsurveillance administered by the InternationalAtomic Energy Agency (IAEA) and supported byregular onsite inspections at declared facilities.IAEA safeguards (see app. 4-C) are intended todetect, and thereby deter, the diversion of suchmaterials from declared peaceful purposes toweapons. Under the NPT, safeguards must beimposed on all nuclear materials possessed bynon-nuclear-weapon state (NNWS) parties, transferredbetween NNWS parties, or transferredfrom any party to any nonparty. 2 The Treaty also2The IAEA traditionally does not consider uranium ore or uranium concentrate to be ‘‘nuclear material’ for safeguards purposes until itis converted into a form suitable for further enrichment (e.g., uranium hexafluoride gas) or for fuel fabrication (e.g., oxide, metal, alloy, orcarbide forms). IAEA safeguards also include an exception allowing declared nuclear material to be removed from safeguards for the purposeof military nonexplosive use, such as for submarin e-propulsion reactors.

— —Chapter 4-Technical Aspects of Nuclear Proliferation 1123requires that no equipment ‘‘especially designedor prepared for the processing, use, or production”of nuclear material shall be transferred byan NPT member to any nonnuclear-weapon state,even one not party to the NPT, unless all nuclearmaterial processed by that equipment is placedunder safeguards. By mandating the adoption ofIAEA safeguards, the NPT is intended to permitstates to pursue peaceful nuclear programs withoutgiving rise to fears of nuclear weapondevelopment.Safeguards are important for all nuclearfacilities, but especially for those dealing withenrichment or reprocessing. Many of the commercialfacilities that enrich uranium for usein power plants, if reconfigured for higherenrichments, would be able to make highlyenriched uranium for hundreds of weapons ormore per year. 3 Moreover, several countriesreprocess spent fuel from nuclear reactors torecover the plutonium generated during reactoroperation, and even pilot-scale reprocessingplants can produce enough plutonium forweapons. Civilian nuclear fuel cycles that includethe use of plutonium and its attendantreprocessing facilities could—if not safeguarded,or if safeguards were violated—be used to produceplutonium for large numbers of weapons.The type of plutonium produced in commercialnuclear reactors under normal operation, calledreactor-grade plutonium, is more difficult to makeinto a weapon than plutonium produced specificallyfor weapons . 4 Nevertheless, reactor-gradeplutonium can be used to make nuclear weaponsof significant (though probably much less predictable)yield, and any state possessing significantquantities of separated plutonium should beconsidered to have the material needed to fabricatenuclear components for nuclear explosivedevices in a short period of timesIAEA safeguards are designed, and to datehave served, to make it very difficult to divert‘‘significant quantities’ of nuclear materialsfrom safeguarded facilities. (The IAEA defines a‘‘signtilcant quantity’ of fissile material as 8 kgof plutonium or 25 kg of highly enriched uraniumseeapp. 4-C.) Indeed, the construction andoperation of nuclear power reactors and othercommercial facilities so as to divert materialsto a weapon program is neither the easiest northe most efficient route to obtain nuclearweapon materials. Moreover, by using modernequipment and measurement techniques, safeguardsmethods have been significantly improvedand in many cases are becoming more automated,more tamper-resistant, and less intrusive to plantoperation. Commercial-scale bulk-handling facilitiessuch as fuel-fabrication plants, uraniumenrichmentplants, and reprocessing facilities,which process large quantities of nuclear materialin often dilute and easily modifiable aggregateform rather than in accountable units such as fuelrods or reactor cores, are more difficult tosafeguard than individual nuclear reactors. However,at present there are no large facilities of this3Almost all civilian power reactors use low-enriched umnium (LEU, see box 4-A), but the enrichment facilities that produce LEU mightalso be used to produce HEU. Recortf@ring some types of enrichment plants, such as gaseous diffusion plants, from producing LEU toproducing HEU would be extremely time-consuming and virtually impossible to accomplish in a safeguarded facility without detection. Onthe other band, reconfiguring gas centrifuge plants could, in theory, be accomplished more easily. Institutional barriers, such as a state’s ownsystem of control and perceived best interests, must supplement technical ones as deterrents to any such recontlgurat.ion.4The states that have been known to or have sought to produce nuclear weapons have made a determined effort to produce weapon-gradematerials specifically for that purpose; no military nuclear weapon program is known to have relied on reactor-grade plutonium.5See, for example, J. Carson Mark, Reactor-Grade Plutonium’s Explosive Properties (Washington, DC: Nuclear Control Institute, August1990).

124 I Technologies Underlying Weapons of Mass Destructiontype under fulltime IAEA safeguards in countriesof particular proliferation concern. 6Still, IAEA safeguards have fundamentallimitations. First, several suspect nuclear proliferantstates are not signatories to the NPT and arenot obligated to place all their nuclear facilitiesunder safeguards. Second, safeguards cannotprevent an NPT member from amassing a stockpileof nuclear weapon materials under safeguards,withdrawing from the NPT, and assertingthat its stockpile is no longer subject to safeguards.Third, while the NPT clearly obligatesmember states to declare all of their nuclearfacilities and place them under safeguards, it doesnot provide a “hunting license” to verify theabsence of undeclared facilities. The IAEA doeshave the power to request “special inspections”at declared or undeclared facilities, should it findreason to do so, but no such inspections ofundeclared facilities (except in Iraq) have everbeen carried out. 7 Therefore, the NPT and theIAEA have very little ability to forestall thedevelopment of nuclear weapons in states thatare not NPT members, and only limited abilityin NPT member states that are able to developa secret nuclear infrastructure outside IAEAsafeguards. Indeed, the covert, indigenousproduction of nuclear materials is now mostlikely a greater danger than the diversion ofnuclear materials from safeguarded facilities.Some of the signatures that might reveal such acovert program are discussed in this chapter.EXPORT CONTROLSExport controls constitute the other primarymeans (besides IAEA safeguards) by which theinternational community can seek to preventproliferant states from acquiring the technicalcapability to develop nuclear weapons. (Mostother nonproliferation policies address the incentive,and not the capability, to develop nuclearweapons .8) One form of export controls is imposedby the NPT, which forbids the transfer ofequipment designed to process nuclear materialsunless it is placed under IAEA safeguards. TheNPT also prohibits nuclear-weapon states fromexporting goods or information that would assistin any way with the development by non-nuclearweaponstates of nuclear weapons.If, despite the NPT, a state were able to importunsafeguarded nuclear material suitable forweapons—perhaps from the former Soviet Unionor from a proliferant state already possessingenrichment or reprocessing facilities-it wouldobviate the need to produce its own weaponmaterial. Such transfers would leapfrog the bulkof the international technical controls againstproliferation. Transfers of low-enriched uraniumare not nearly so dangerous, since they do noteliminate a proliferant state’s need to developcomplex enrichment facilities. However, if aproliferant already has such facilities, feedingthem with LEU rather than natural uranium caneasily more than double their capacity to produceweapon-grade uranium.Jolted by India’s “peaceful nuclear explosion’in 1974, several industrialized countries collec-6Note that only facilities under jid-ritne safeguards are considered here, since those not safeguarded or safeguarded only part of the time(e.g., when safeguarded fuel is prestmt) cannot be expected to be verifiably free from diversion at other times. (Argentina and hdi% for instance,have some nuclear facilities under part-time safeguards, and Kazakhstan has a fiel-fabrication plant not yet under safeguards, though it ismoving toward accession to the NPT and thus to full-scope safeguards.) Brazil has a medium-size fuel-fabrication facility under IAEAsafeguards and, with South Africa’s accession to the WT. that country’s enrichment facilities are also being placed under full-scope safeguards.But neither state is considered a fnst-order proliferation threat at present.7The IAEA’s first attempt at requesting such a special inspection was directed at North Korea in early 1993 and was refused. Subsequently,the IAEA declared North Korea to be in violation of its safeguards agreement and referred the matter to the United Nations Security Council,which is addressing the issue. As of November 1993, the dispute was still under negotiation.g Incentives and other policy tmds, such as security guarantees, cooperation and development assistance, regional arms control, and threatsof U.N. or other intenentiom are filtroduced in ch. 3 of the OTA report Proliferation of Weapons of Mass Destruction; Assessing the Risks,op. cit., footnote 1.

Chapter 4-Technical Aspects of Nuclear Proliferation | 125tively decided to impose export controls thatwould extend beyond those required by the NPT.Forming the Nuclear Suppliers Group in 1975,these countries initially agreed to exercise restrainton the transfer of any goods or systemsdirectly applicable to the production of nuclearweapon materials (e.g., nuclear reactors andreprocessing equipment for separating plutonium,or systems such as gas centrifuges orgaseous diffision systems for enriching uranium).9 As a result, the export of most suchsystems today is tightly constrained. Togetherwith the required imposition of IAEA safeguards,these controls have made it verydifficult for would-be proliferant states toacquire “turn-key” systems to produce nuclearweapon materials. However, technologiesfor some older enrichment methods (e.g., thecalutrons for electromagnetic separation, used byIraq) and some components for not-yetcommercializedmethods (e.g., lasers useful forresearch on some advanced separation techniques)have been more easily obtainable. Moreover,rather than importing complete systems toproduce nuclear materials, some proliferant statesnow possess and others are attempting to buildtheir own equipment, drawing on “dual-use’technologies such as high-voltage power supplies,high-strength alloys and carbon-fiber products,high-performance ion-exchange resins andliquid-liquid contacting equipment, precision machinetools, welding equipment, and specializedfurnaces that also have legitimate civil (nonnuclear)applications. Spurred largely by Iraq’sprogress toward nuclear weapons as revealedafter the Persian Gulf War of 1991, the 27countries of the Nuclear Suppliers Group recentlyextended their controls to include a wide array of‘‘dual-use’ technologies (see app. 4-D), thusclosing many loopholes in previous nuclearexport controls.Computers are an important class of dual-usegoods, having widespread applications in civil aswell as weapon-related fields. Useful as they maybe for nuclear weapon development, however,advanced high-performance computers (so-called‘‘ supercomputers ‘‘ in the 1980s) are by no meansnecessary for design of first-generation fissionweapons even in the absence of nuclear testing;placing strict limits on their exports would be ofonly secondary importance compared to limitingtechnologies for nuclear-materials production.Computers of lesser capability are more thanadequate for first-time proliferants and are becomingincreasingly difficult to control as theirproduction spreads around the world. However,advanced computers are relatively more importantfor proliferants pursuing advanced nuclearweapons, including thermonuclear ones.In addition to nuclear materials and weaponrelatedtechnology, expertise is a key ingredientin making nuclear weapons. Although specificdetails remain secret, basic principles of nuclearweapon design have been widely known fordecades and cannot be controlled. Moreover, theprogress made by successful nuclear proliferantsshows that dedicated research programs can fill inthe engineering details. First-time proliferantsin the 1990s could and probably would buildnuclear weapons considerably smaller andlighter than the first U.S. weapons. Nevertheless,“weaponizing” a nuclear warhead for reliablemissile delivery or long-term shelf-life addsadditional technical difficulties and could significantlyincrease the research and developmentefforts needed to field it. Should they offer theirservices, skilled weapon designers from theacknowledged nuclear powers could significantlyaccelerate the progress of a proliferant’s nuclearprogram, primarily by steering it away fromunworkable designs. They would also be particularlysignificant in the fields of isotope-separation9Not only are tbcse export controls not mandated by the Nuclear Non-Proliferation Treaty, but many countries, particularly developingstates, argue that they violate the NPT obligation upon industrialized states to participate in “the fullest possible exchange of equipment+materials and scientific and technological information for the peaceful uses of nuclear energy’ ~, Article IV, Section 2).

126 I Technologies Underlying Weapons of Mass Destructiontechniques or plutonium production. Such individualscould fill critical gaps in a proliferant’sknowledge or experience, adding greatly to thelikelihood that its programs would succeed. Theycould also increase the range of sophistication ofdesigns feasible without testing. Therefore, continuingto protect subtle weapon design detailsand preventing experienced weapon-system scientistsand engineers from emigrating or sellingtheir services to proliferant states will be importantadjuncts to export-control policy.| Difficulty and Detectability of NuclearProliferationProducing nuclear weapon materials indigenouslywould require at least a modest technologicalinfrastructure and hundreds of millions of dollarsto carry out. The costs of a full-scale indigenousprogram, however, especially if clandestine andlacking outside nuclear-weapon expertise, can beas much as 10 to 50 times higher than for aprogram aimed at producing just one or twobombs and largely carried out in the open or withoutside technical assistance. Prior to the GulfWar, Iraq spent many billions of dollars-over 20times the cost of a minimal program-to pursuemultiple uranium-enrichment technologies, tobuild complex and sometimes redundant facilities,to keep its program as secret as possible, andto begin to lay the foundation for a fairlysubstantial nuclear capability. Few countries ofproliferation concern could match the resourcesthat Iraq devoted to its nuclear weapon program.(Iran probably could, however, if it so chose.)In the near term, low- and medium-level gascentrifuge technology may become increasinglyattractive to potential proliferants, forreasons including the availability of informationon early-model centrifuge design, the widespreaduse of and possible illicit access to know-how formore advanced centrifuge technology, and therelative ease both of hiding centrifuge facilitiesand using them to produce highly enricheduranium (HEU). The more advanced centrifugetechnology, once obtained, could lead to small,efficient, and relatively inexpensive facilities thatwould be particularly difficult to detect remotely.Because of their small size and potential forhigh enrichment in few stages, laser isotopeenrichment techniques could prove to be difficultto detect and control if successfully developedin a clandestine program. l0 Nevertheless,except in the advanced industrial countries, constructingoperational laser-enrichment facilitieswill remain very difficult. (Industrial-scale facilitiesremain difficult even for the advanced countries.)Therefore, it is unlikely for at least anotherdecade that these technologies would play asignificant role in nuclear programs of developingcountries.The published data and recent successes inJapan and France, respectively, with ionexchangeand solvent-extraction enrichmentmethods relying on conventional chemicalengineeringprocesses, make these techniquespotentially a more serious proliferation concernthan they had previously been thought.Aerodynamic enrichment techniques, whichuse carefully designed nozzles or high-speed gasflows to separate isotopes by mass, have beensuccessfully developed by Germany and SouthAfrica. Some aerodynamic techniques requirefairly sophisticated technology to manufactureprecision small-scale components, but are otherwiseconceptually straightforward and arecapable of producing HEU. 11 If strict controlsare not maintained on these technologies, theycould pose proliferation risks.Gaseous diffusion technology, developed byeach of the five declared nuclear powers, forms10 kw e~c~ent tahologi= we precisely tuned laser beams to selectively energize the uranium-235 isotope most useful for nuclemweapons and separate it from the more common uranium-238 isotope (see app. 4-B on enrichment technologies).1 I A pnncip~ ~lc~~ in constructing aerodynamic enrichment facilities, however, is obtaining pumps, seals, and comp=sors tit wcresistant to uranium hexafluoride.

Chapter 4-Technical Aspects of Nuclear Proliferation 127the basis for much of the world’s current enrichmentcapacity, but it has proven difficult for othercountries to develop and does not appear to be aslikely to be pursued by proliferant states as someother methods.The process of acquiring or constructing theappropriate facilities and then producing nuclearweapon materials in them provides manysignatures and the greatest opportunity fordetecting a clandestine nuclear weapon program.The development and testing of nuclearweapon components provide significantly fewerobservable indicators. Assembly and deploymentof a small number of weapons themselves mightsimilarly not be easily detected, although specializedpreparations for aircraft or missile deliverymight be more readily seen. Deploying largenumbers of nuclear weapons, however, might callfor new military doctrine and elaborate training,security, and support systems, thus increasing thenumber of people involved and the possibilitythat information about the program might beleaked. Sufficiently large nuclear tests (possiblyat the kiloton level; certainly at the 10 kt level)would probably be detectable by various means,but they are not necessary for fielding firstgenerationfission weapons with reasonably assuredyields.Iraq and South Africa demonstrated that withenough effort and financial resources, a countrycan hide from international view both the size andspecifics of its nuclear weapon program-thoughcertainly not all evidence of its existence, Iraq, forexample, though party to the NPT, clandestinelypursued an ambitious program outside of safeguards,while maintaining a massive internalorganization and extensive and carefully developedchannels of foreign technical assistance(many of which have now consequently beensubject to more stringent controls). Therefore,although technology restrictions can retardproliferation, and verification procedures andmonitoring technologies can help detect andthus deter proliferation, the primary barriersto proliferation of nuclear weapons in the longterm remain institutional rather than technological.A state’s perception of its own securityand national interests, and whether it believesa nuclear weapon program would serve thoseinterests or detract from them, play majorroles in the decision process.ACQUIRING NUCLEAR WEAPONCAPABILITYFor most of the nuclear age, purchasing orstealing nuclear weapons has been relatively easyto dismiss, since the nuclear powers controlledtheir weapons very tightly. However, the collapseof the Soviet Union for the first time has posedreal concerns over the security of nuclear weaponsthemselves, as well as over weapon materials,components, design information, related technology,and expertise. 12 The following section addressesthe potential diversion of Soviet nuclearweapons; it is followed by a discussion of themore traditional problem of preventing statesfrom manufacturing their own nuclear weapons.| “Loose Nukes” in the Former SovietUnionVarious unconfirmed reports in the firstmonths of 1992 in the European press andelsewhere claimed that Iran had purchased severaltactical nuclear warheads or their componentsfrom one or more newly independentIslamic republics of the former Soviet Union. 1312 See, for example, Oleg B ukharin, The Threat of Nuclear Terrorism and the Physical Security of Nuclear Installations and Materials inthe Former Soviet Union, Occasional Paper No. 2 (Monterey, CA: Center for Russian and Eurasian Studies, Monterey Institute of InternationalStudies, August 1992).13 See, for e=mple, Yossef BOdaIISICY, “Iran Acquires Nuclear Weapons and Moves to Provide Cover to Syria,” Defense and ForeignAjfairs Strategic Policy, February 1992, Special Section, pp. 1-4; and FBLS, WEU-92-054-A, Mar. 19, 1992 (about a report in the Mar. 15,1992 issue of the German magazine Stern).

128 I Technologies Underlying Weapons of Mass DestructionSince nuclear artillery shells, short-range rockets,aerial bombs, and other tactical weapons intendedfor battlefield use are readily portable, suchreports are cause for concern. Nevertheless,senior Russian intelligence officials have claimedthat they know where every one of their weaponsis and that none is missing. 14 Furthermore, U.S.officials have said, without asserting that theyknow the whereabouts of every Soviet nuclearweapon, that they are not aware of any independentevidence corroborating such transfers. 15 Pastattempts to purchase nuclear warheads, such as byLibya from China, have been reported, but neverknown to be successful. 16By mid-1992, according to Russian officialsand later supported by CIA director R. JamesWoolsey in congressional. testimony, 17 all tacticalnuclear weapons had been returned to Russiafrom non-Russian republics. However, since thepolitical situation in Russia is far from settled,removing nuclear weapons from the other republicsto Russia does not resolve questions concerningthe weapons’ security. Moreover, strategicweapons—the higher yield, bulkier weaponsdesigned for intercontinental missile or bomberdelivery-are still based in three non-Russianrepublics (Ukraine, Belarus, and Kazakhstan),raising questions over the: ultimate status of theserepublics as nuclear or non-nuclear powers.Even if whole nuclear weapons were transferredto a non-weapon state, it is unlikely in mostcircumstances that they could be detonated intheir present form. All strategic and many tacticalweapons in the former Soviet Union are believedto be configured with “permissive action links”(PALs) or equivalent controls that preclude theirdirect detonation except upon introduction of aspecial code. 18 However, the level of sophisticationof Soviet PALs is not known, and many—especially early models-may be comparativelyrudimentary, not integral to the weapon, orentirely absent. l9 Such devices cannot be presumedto delay indefinitely a technically sophisticatedindividual or team that had prolongedaccess to the weapon.Moreover, a smuggled weapon would constitutea serious danger even if it could not bedetonated. First, disassembly by suitably trainedindividuals could provide valuable first-handinformation on its design, materials, and components.Second, the weapon’s nuclear materialsmight be recovered for use in another weapon. Assuch, transfer of any warhead to any nonweaponstatewould be cause for serious concern, evenif its immediate utility as a detonable devicewere low.| Manufacturing Nuclear WeaponsAspiring proliferants unable to purchase orsteal nuclear weapons, or unwilling to rely on solimited an arsenal, would have to manufacturethem on their own. The following sections14 pad W.Judge, t c~ Repul}fics, h Eye on Bombs, Scientists,” Boston Globe, June 23, 1992, p. A14; ~ Mary ~us, ‘ ‘U.S. S*to Stop Stockpile Leaks,” Boston Clobe, June 24, 1992, p. 22.1S See, for emple, R. James Woolsey, Dir&tor of cen~~ ~~~igence, &stfiony before the Senaw committe On &WerIIIIEXlti Affairs,Feb. 24, 1993.16 ~onad s, sPCtor ~i~ J~Ue~e R. Smi@ Nuc/earA~itions: The spre~ of NuC/ear Weapow, Zgg%lgg(l (Boulder, CO: V/estviewPress, 1990), pp. 175, 178, and references therein.17 ~~ony of R. James Woolsey, Feb. 24, 1993, op. cit., footnote 15.18 Km M. cmp~ll et ~,, Sol,iet Nuclear Fission: Conflol Of the Nuclear ArSe~l in a Disintegrating soviet union, CSIA Studies inInternational Security, No. 1 (Cambridge, MA: Center for Science and International Affairs, Haxvard University, November 1991), pp. 13-17.Although the fmt PALs used on U.S. weapons were simple mechanical combination locks, subsequent designs have become moresophisticated; many now include disabling devices thac upon attempts at unauthorized intrusio~ can destroy critical warhead components,rendering the warhead undetonable, Warheads also traditionally include environmental sensing devices, which although more easily bypassedthan intrusion sensors in PALS, enable the warhead to detonate only after it undergoes the proper stockpile-to-target or launch sequence (e.g.,changing barometric pressure, acceleration, etc.).19 Ibid., p. 15.

Chapter 4-Technical Aspects of Nuclear Proliferation 129describe and analyze the various steps required toproduce nuclear weapons, identfying the pointsat which international nonproliferation effortsmight have the greatest leverage.This chapter focuses on covert nuclear weaponprograms. Since 1964, when China detonated itsfirst nuclear device, no country has openlyadvertised developing a nuclear weapon capability,even though several states are suspected ofhaving mounted nuclear weapon programs sincethen. 2o India, a non-NPT state, detonated aso-called ‘‘peaceful nuclear device’ in 1974, butdenies having a nuclear weapon program. Evidently,international norms against nuclear proliferation(or the reactions of regional adversaries)have been sufficient to prevent emerging nuclearpowers-even those not members of the NPT—from advertising their programs too openly .21A successful proliferant must overcome anumber of technical hurdles. Among them are:obtaining enough fissile material to form asuper-critical mass for each of its nuclear weapons(thus permitting a chain reaction); arriving ata weapon design that will bring that mass togetherin a tiny fraction of a second, before the heat fromearly fissions blows the material apart; anddesigning a working device small and lightenough to be carried by a given delivery vehicle.These hurdles represent threshold requirements:unless each one is adequately met, one ends upnot with a less powerful weapon, but with adevice that cannot produce any significant nuclearyield at all or cannot be delivered to a giventarget. Table 4-1 and figure 4-1 outline the stepsrequired to produce and deploy nuclear weapons.Both the figure and the table show the two basicapproaches for acquiring nuclear materials: enrichinguranium to highly enriched levels, orirradiating uranium in a nuclear reactor followedby reprocessing to separate out the plutonium. 22They also portray the weapon design, fabrication,and deployment stages.SOURCES OF NUCLEAR MATERIALSA potential proliferant has three options foracquiring fissile material needed for a nuclearweapon: purchase or theft, diversion fromcivilian nuclear activities in violation of IAEAsafeguards, or indigenous production in unsafeguardedfacilities. Each of these routes is prohibitedto NPT non-nuclear-weapon states and tostates that are parties to nuclear-free-zone treatiessuch as the Treaty of Tlatelolco; such states areprohibited from operating unsafeguarded nuclearfacilities. Any unsafeguarded facilities that suchstates did operate would presumably be runcovertly. Non-NPT states such as Israel, India,and Pakistan are under no treaty obligations torefrain from acquiring, producing, or sellingfissile materials or to place all their nuclearproduction facilities under IAEA safeguards (somecome under safeguards when processing safeguardedmaterial supplied by NPT states), butthey might well seek to keep unsafeguardedactivities secret anyway.Indigenous production of weapon-grade nuclearmaterial requires a large, complex, andexpensive set of specialized facilities, and the20 Evid~e Of ~ ~~~’~ d~i~ion to “go nucl~” need not ~ -tic, M it WM with the bp&tiOns in kiq fC)~OWiIlg the 1991 GulfWar, with Mordemii Vuumu’s revelations about Israel’s nuclear program, or with India’s “peaceful” detonation in 1974. Instead, evidenceof a country’s potential intent and capability can unfold slowly over tie. The latter has &en the case with North Korea and@ and beforethey opened up their facilities to safeguards, with South Afi@ Argentina, and Brazil. South Africa’s program was subsequently also revealedin a more dramatic fashion by President F.W. de Kler~ when he announced in March 1993 that South Africa had assembled six nuclear weaponsin the 1980s.21 my nonwoliferation sw~sw, howev~, WOW that a open nuclear arms race my erupt between ~~ ~d P~s@k both of whichare “threshold” states considered either to have nuclear weapons or to have the capability to construct them on short notice.22 ~orim cm &SO be irradiatd in nuclear reactors to produce the fissile isotope uranium-233, which can then be separated for use in nuclearweapons by chemical reprocessing similar to that for plutonium. However, thorium-based fuel cycle technology has not been developed to thepoint where it would present a likely proliferation route.

130 I Technologies Underlying Weapons of Mass DestructionAcquisition of nuclear weapon materials■ Mining of uranium-bearing oreTable 4-l-Steps to Produce and Deploy Nuclear Weapons■ Milling to extract uranium concentrate in the form of “yellowcake” (U 30 8) or other uranates a● Chemical processing to convert yellowcake into useful compounds (such as U0 2, UF G, UF 4, UCl 4)-Uranium-235 based weapons:, Enrichment of uranium to high levels of uranium-235 (most often carried out using uranium hexafluoride, UF 6,or other uranium compounds)Conversion of enriched uranium product to uranium metal---Plutonium-based weapons:Uranium fuel fabrication in the form of metal or oxide (using alloys, ceramics, zircalloy or aluminum cladding, etc.)■ Reactor construction and operation (typically requiring a graphite or heavy-water moderator b , unless enricheduranium fuel were available)■ Reprocessing of spent fuel to extract plutonium product■ Conversion of plutonium product to plutonium metalWeapon fabrication (plutonium or uranium weapons)■ Design and fabrication of fissile core■ Design and fabrication of nonnuclear components (chemical explosives, detonator, fuze, neutron initiator,reflector, etc.)Weapon assemblyWeapon testing and deployment■ Physics tests (hydrodynamic, hydronuclear, or nuclear—see text)Development of delivery system and integration with warheadWeapon transport and storage■ Possible development of doctrine and training for usea tJ308 can also be pur~~~ On ttw international market; transfers to or from NPT parties with safeguards agreements in force must be reportedto the IAEA, but do not require insloections.b The moderator i n a nu~ear reactor slows down the neutrons produced in fission reactions so that they can more efficiently induce subsequentfission reactions. Heavy-water and ultra-pure graphite are effective neutron moderators having very low neutron absorption, thus permittingreactors to operate on natural uranium.SOURCE: Stephen M. Meyer, The ,Dyrramks of Nmlear Proli~eration, (Chicago, IL: Univ. of Chicago Press, 1984), p. 175; and OTA.relevant facilities therefore represent principal“chokepoints" for controlling nuclearproliferation. Unless a state succeeded in importingor otherwise acquiring weapon-usable materialdirectly, producing such material in dedicatedfacilities is likely to cost many times whatit would cost to design and fabricate other nuclearweapon components. Moreover, the nonnucleardevelopment work could be funded and carriedout well in advance of the supply of suitablenuclear materials (as was the case in Iraq), and itis much harder to monitor and control thannuclear material production.This section discusses various sources wherenuclear materials might be stolen or diverted toweapon use; it is followed by a discussion ofrequirements for manufacturing such materialsindigenously.Diversion or TheftNuclear materials, some of which are relativelyeasy to convert into forms directly usable innuclear weapons, are stored at and transportedamong hundreds of civilian nuclear facilitiesaround the world. These stockpiles and transfersinevitably introduce some risk of theft or diversion,depending on the material and the level of itsprotection. Theft of weapon-grade nuclear materialswould be more serious than that of material

Chapter 4-Technical Aspects of Nuclear Proliferation 131requiring substantial additional processing. If aparticular stockpile were poorly safeguarded,diversion of material might not be detected beforeit had already been fabricated into a weapon. Sucha clandestine diversion would probably constitutea greater danger than the hijacking of a shipment,which would certainly be noticed and mighttrigger military or other action to recover thestolen material or prevent its being used.The low-enriched uranium (LEU) that fuelshundreds of nuclear power reactors worldwidecannot be used directly to make nuclear weapons.If used instead of natural uranium as a feedstockfor a proliferant state’s own uranium enrichmentprogram, however, it can speed up considerablythe production of highly enriched uranium forweapons. Furthermore, civilian nuclear reactorsconvert part of their uranium fuel into plutoniumas they operate.23 When separated from theunconsumed uranium fuel and the radioactiveby-products produced during reactor operation—a step called reprocessing—the plutonium soobtained can be reused in nuclear reactors.However, it can also be used to make a weapon.By the year 2000, hundreds of tonnes of plutoniumwill have accumulated worldwide in civilianspent fuel, and with current plans, over 100tomes will have been separated and stored. Thispotential coupling between civil nuclear powerand nuclear weapons is a fundamental reason forthe International Atomic Energy Agency’s systemof nuclear safeguards (see app. 4-C). 24Due in part to IAEA safeguards, individualcommercial power reactors are neither themost vulnerable nor the most fruitful sites fordiverting nuclear materials. Several possiblesources of nuclear materials described below posegreater risks of theft or diversion than do commercialnuclear power reactors. Similarly, facilitieswhere nuclear materials are handled in bulk(enrichment, fuel-fabrication, and reprocessingplants) pose substantially greater diversion risksthan do commercial power reactors, but areconsequently inspected much more often. In anycase, there are no large bulk-handling facilitiesunder full-time safeguards in countries of currentproliferation concern. 25REACTOR-GRADE PLUTONIUM AND NUCLEARWEAPONSReactor-grade plutonium recovered from civilianreactors differs from weapon-grade plutoniumin the relative proportions of various plutoniumisotopes (see box 4-B). Reactor-grade plutoniumhas a higher rate of spontaneous fission reactions23 Reactors containing significant amounts of uranium-238 produce plutonium at a rate of about 1 gram per day per megawatt-thermal(MW(t)) of reactor power, or about 10 kg per year for a 30-MW(t) reactor running 90% of the time. Note that commercial reactors are usuallyrated in terms of the electn”caZ power they produce, in units of megawatts-electric (MW(e)), whereas research reactors andplutonium-production reactors are rated in terms of overalt thermal power, MW(t). Since about two-thirds of the power used to generateelectricity y becomes waste heat, a typicaI Iarge commercial nuclear power plant that generates 1,000 MTV(e) would have a thermal power ofabout 3,000 MW(t).M The 1977 OTA report~uclea~ Pro/ifer4tion and Safeguards, OTA-E-48 (Washington DC: U.S. Government ~tig office, June 1977),and appendices, vol. 2, parts 1 and 2, discusses the relationship between nuclear power, nuclear weapons, and international safeguards. TheU.S. Department of Energy presented a detailed technical assessment of these relationships in Nuclear Proll~eration and Civilian NuclearPower, Report of the Nonproliferation Alternative Systems Assessment Program (NASAP), DOE/NE-0001/1, vols. 1-9, June 1980. Otherreferences discussing nuclear safeguards include ‘‘Materials Management in an Internationally Safeguarded Fuels Reprocessing PlanL” LosAlamos Scientific Laboratory Report IA-8042, vols. I-III (April, 1980); David Fischer and Paul Szasz, Safeguarding the Atom: A CriticalAppraisaZ (Lmdon: SIPRI, Taylor and Francis, 1985), especially ch. 7 and apps. II and III; Lawrence Scheinm~ The International AtomicEnergy Agency and World Nuclear Order (Washington DC: Resources for the Future, 1987), especially chs. 4 and 5; MEA Btd[en”n, forexample, vol. 32, No. 1 ( 1990); and Journal of Nuclear Materials Management, for example, vol. 20, No. 2 (l?ebruary 1992).25 India operates reprocessing facilities that are under safeguards only when reprocessing safeguarded tIsanium fuel. This leaves ~di% anon-NPT state, with the capability to separate plutonium for weapon use with this facility at other times. North Korea’s alleged reprocessingfacility at Yongbyon has been declared to the IAEA but has not yet been fitlly placed under safeguards. Brazil has a medium-sized fuelfabrication facility under IAEA safeguards, and South Africa’s enrichment facilities have come under safeguards with its accession to the NPT,but neither state is considered a first-order proliferation threat at present.

132 I Technologies Underlying Weapons of Mass Destructionthan weapon-grade, generating neutrons that caninitiate the nuclear chain reaction during weapondetonation sooner than would be optimal. As aresult, using reactor-grade plutonium in a firstgenerationnuclear weapon can significantly reduceboth the predictability and the expectedyield of a weapon designed by a proliferant state.None of the states that have either madenuclear weapons or attempted to do so appearto have selected anything but high-qualityplutonium or uranium for their designs. Nevertheless,from a technical perspective, reactorgradeplutonium can be used to make nuclearweapons (see box 4-B), and any state possessingsignificant quantities of separated plutoniumshould be considered to have the materialneeded to fabricate nuclear componentsfor nuclear explosive devices in a short periodof time.REPROCESSING PLANTS AND SEPARATEDPLUTONIUMSeveral hundred tonnes of weapon-grade plutoniumwill likely be recovered from dismantledU.S. and Russian warheads over the next decadeand stored at facilities in those two countries .26 Inaddition to this plutonium, large quantities ofseparated plutonium from civilian reactors aroundthe world continue to accumulate and be stored atfour principal reprocessing sites: La Hague andMarcoule in France, Sellafield in Britain, andChelyabinsk in Russia. 27Reactor-grade plutonium separated from spentfuel can be used either in a new generation ofcivilian reactors designed especially to use plutoniumfuel, or in conventional nuclear reactors,where it can substitute for the uranium-235 insome portion of the LEU fuel. 28 However, unlessthe utilization of separated plutonium increasesdramatically, it is almost certain that the currentsurplus of over 70 tonnes of stored separatedplutonium will increase by another 100 tonnes bythe year 2000. 29 Eventually, most of the foreignownedplutonium at the sites in France and theU.K. is contractually obliged to be returned to itscountries of origin-most of whom are notnuclear weapon states 30 —thus significantly increasingthe transport and handling of plutoniumaround the world. By the end of the century, anadditional several hundred tonnes of unseparatedplutonium worldwide will also have accumulatedin spent reactor fuel. 31M see U.S. Congess, Office ,Df mhnolo= Assessment Dismantling the Bomb and Managing the Nuclear Materials, 0~-o-572(Washington DC: U.S. Government Printing CMce, September 1993). Safeguarding the storage and ultimate disposition of nuclear materialsfrom dismantled weapons in the former Soviet Union is a high U.S. priority and is the subject of intense ongoing discussions with Russia.27 Smti ~omwci~ ~prme~s~ facilities me ~so opemt~ at ~~.m~ ~ Jap~ ~d TWWM iI.I India, md have opemted ixI the p~tin the United States (West lhlley, New York), Germany (Karlsruhe), and Belgium @roch6mic-Mel). India is building an additional facilityat Kalpakkam, possibly to begin operation in 1993-94, and Japan is planning to ftish constructing a major reprocessing facility atRokkasho-mura by about 2005. Reprocessing facilities for separating Russian military plutonium are located at two additional sites: Tomsk-7and Krasnoyarsk. See Frans Berkhout et al., “Disposition of Separated Plutonim” Science & Global Security, vol. 3, No. 1, 1992, table 2,p. 7.28 pluto~@ for use k convmtio~ nucl~ reactors is usually combined with natural or low-enriched urtim in their oxide forms ~02and PU0 2) to make mixed-oxide fuel or MOX. MOX having a plutonium concentration of about 3 to 5Y0 of the uranium concentration can beused to replace about a third of the fuel rods in some types of conventional light-water reactor. Fast breeder reactors (FIRs) fueled primarilyby plutonium are currently being developed by Japa Ch@ and Kazakhstan. France (which has shut down its Superph4nix breeder reactor)and the U.K. are no longer as actively involved with breeder development as they had been in the past.29 ~or t. 1991, abut 120 tomes of civfi~ RGPu had been separated worldwide at the four facilities mentioned, of which 37 tOnneS htidbeen recycled in advanced I@id-metal reactors (mostly in demonstration breeder reactors) and another 12 tonnes as MOX fiel for conventionallight water reactors (LWRs). From 1991 through 2000, another 190 tomes are contracted to be separated, primarily at reprocessing plants inGreat Brita.@ France, and Japa.q of which only about 70-80 tonnes are expected to be recycled in reactors.qo These countries include Belgiuxq Finland, Germany, Italy, Jap~ Netherlands, ~d Switirlmd.31 Fr~BerJ&ou~ ~toli Di~ov,~oldFeiveso~ Marvin Miller, and Frank von Hippel, ‘ ‘Plutonium: True @iUXiOnhXkty,’ ‘Bulletinof the Atomic Scientists, vol. 48, No. 9, November 1992, pp. 28-34.

Chapter 4-Technical Aspects of Nuclear Proliferation 133Box 4-B—Reactor-Grade PlutoniumPlutonium produced in a reactor continues to be exposed to neutrons until the fuel is removed from thereactor. This prolonged exposure results in the buildup of other plutonium isotopes (atomic numbers 238,240,241,242) in addition to plutonium-239. 1 The even isotopes of plutonium have a high probability of spontaneous fissionand thus neutron emission, plus several other deleterious neutronic effects in weapons. By current U.S. definition,reactor-grade plutonium contains at least 20 percent even (non-fissile) isotopes, whereas weapon-grade contains6 percent or less.Because the non-239 plutonium isotopes are more radioactive and emit more spontaneous neutrons, theymake the design of a plutonium weapon more difficult (virtually lmpossible at high concentrations of Pu-238). Theproblems are at least two-fold. From the perspective of bomb performance, if too much plutonium-240 or -242 ispresent its spontaneous neutrons have a high probability of starting the chain reaction too soon, thus substantiallyreducing the yield. Second, reactor-grade plutonium generates 6 to 10 times more heat per unit mass than doesweapon-grade plutonium, 2 and an IAEA significant quantity of RGPu (8 kg) would generate well over 100 wattsof heat. 3Nevertheless, the critical mass of RGPu is only about 25 percent higher than that of weapon grade, andnuclear explosive devices can be designed that use it. 4 Plutonium with a nonfissile concentration (plutonium 240plus 242) as high as 50 percent-as might be recovered from very high burn-up LEU fuel or MOX fuel-can alsobe used to make explosive devices having kiloton yields?1 Altholigh65 percent of the neutrons captured byplutonium-239 cause ittofission, the retining35perCentareabsorbedtocreate ptutonium-240. Other higher isotopes are formed simllarty. Reactor-grade plutonium normallycontinues to be exposed in a reactor for up to a few years. VWapon-grade plutonium is produced from uranium-238that Is exposed for only a relatkely short the, possibly on the order of weeks.2 plubnium recovered from spent LEU or MOX fuel after 10 years of storage generates 14 to 24 W~9-Pu,whereas weapon-grade plutoniumgenerate sonly 2.4 W/kg-Pu. P/utonlumFue/;% Assessmnt (Paris: OECWNEA,1989), tables 9,128, as cited in Frans Berkhout, Anatoli Diakov, Harold Feiveson, Helen Hunt, Edwin Lyman, MarvinMiller, and Frankvon Hippel, “Disposition of Separated Plutonium,” S&me& G/oha/ Secuclty, vol. 3, No. 1,1992,p. 10.3 If this rnuch RGPu were left surrounded with high explosive of low thermal conduCtivhy, such as in animplosion device, it could generate temperatures above 200 “C, depending on the design.4 See J. Carson Ma~ Reactor-Grade Phdonium’s Explosive Properties (Washington, DC: Ntiear Controlinstitute, August 1990).5 Alex DeVo@i, “Fissi[e Materials and Nuclear Weapons Proliferation,” Ann. Rev. ~ud. Paff. *I., vol. 36, P.108 (table 4), In addition, based on declassified information, Maj. (3en. Edward B. Giller, deputy assistantadministrator for national security for the U.S. Energy Research and Development Administration, stated inSeptember 1977that the U.S. detonated anucleardevice in 1962 using low-grade plutonium typlcai of that producedby dvilian power plants (Robert Gillette, “Impure Plutonium Used In ‘62 A-Test,” &s Angeles ?lnes, Sept. 16,1977,p. A3), thus providing experhmntal confirmation that such matedal could be used to build an atomic weapon. (Neitherthe isotopic composition of the plutonium used nor any yield information was released; at the time, reactorgradeplutonium was defined to contain greater than 8 percent of the isotopes Pu-240 and Pu-242.) See atso PaulLeventhal, ‘%Wapons-Usable NudearMaterials: Eliminate Them?” In Dl=t&sSdesonPm/if-tlon, Kathleen C.Bailey, cd., Lawrence Livermore National Laboratory, UCRL-LR-1 14070-1, June 7,1893, p. 34.

134 I Technologies Underlying Weapons of Mass DestructionBox 4-C-Japanese Shipments of Separated PlutoniumAfter two decades of shipping spent fuel to Europe for reprocessing and storage, Japan has now begun amajor program to ship back large quantities of separated plutonium from its LWR spent-fuel. Shoe the UnitedStates originally supplied this fuel, it has the right under the revised 1987 U.S.-Japan Nuclear CooperationAgreement to approve or reject the final security plans for the shipments. Current plans call for up to30 or40 tonnesof separated plutonium to be returned to Japan by the year 2000, using four or five shipments per year.Since the early 1980s, shipments of plutonium by sea have required extraordinary security arrangements.Even so, a 1988 Pentagon study stated that ”...even if the most careful precautions are observed, no one couldguarantee the safety of the cargo from a security incident, such as an attack on the vessel by small, fast craft,especially if armed with modern antiship missiles.” 1 However, unless the attackers were able to board the shipand carry away the plutonium before it sank or before additional security forces arrived or could pursue them, thismay not be a very credible diversion scenario. Similarly, scenarios to commandeer the ship and evade theinevitable pursuit do not seem very credible. Therefore, at least from a security standpoint, fears over Japaneseshipments of plutonium may be exaggerated. Nevertheless, if such shipments become commonplace, thepotential risk of such an attack may increase. 21 “Transportation Alternatives for the S&we Transfer of Plutonium from Europe to Japan,” SeaTransportation Alternatives, U.S. Dept. of Defense, Mar. 7,1988.z s-, for e~~e, David E. Sartger, “Japan’s Plan to Import Piutonium Arouses Fear that Fuel Could BeHiJaoked,” /Vew York TOrws, Nov. 25, 1991, p. D8.—Except for the few countries with unsafe- material can be shipped in much smaller andguarded reprocessing facilities (Israel, India, and lighter quantities than can complete weapons, andpossibly North Korea 32 ), obtaining plutonium for in forms that (unlike weapons) are not discrete,weapon purposes would require its diversion at countable units. Significant amounts of nuclearthe foreign reprocessing facility and subsequent material could conceivably escape without detectionby accounting procedures-specially atillegal transfer to the target country, or diversionfrom safeguards within the country to which itbulk-handling facilities. Indeed, numerous allegationsthat former Soviet weapon materials havehad been returned (see box 4-C). Such stepswould be legally risky and perhaps very costly tobeen offered on the black market have alreadyattempt in secret, but they remain a possibility.appeared in the press. 33 So far, the U.S. CentralMATERIAL LEAKAGE FROM FORMER SOVIETIntelligence Agency reports that it has not beenREPUBLICSable to verify any transfer of weapon-gradeIf security and control of the former Soviet materials in significant quantities, and its directornuclear weapon establishment breaks down, the has testified that ‘most reports of transfers appeardiversion of nuclear materials maybe more likely to be scams, hoaxes, or exaggerations. ’ Howthanthe smuggling of intact weapons. Weapon ever, it is impossible to be certain that all are. 3432 NOW Korm hw su~pend~ its ~Omced ~tention to withdraw from the Nuclear Non-Proliferation ‘1’reaty and is therefore sti bo~dby its safeguards agreement with the IAEA, but has not yet resolved its dispute with the IAEA concerning the conditions of this agreement.The IAEA has therefore been unable to confirm North Korea’s adherence to safeguards.33 see, for Cxmple, MiUC Fishe:r, ‘‘Germany Reports a Surge in Nuclear Smuggling Cases,’ Washington Post, Oct. 10, 1992, p. A27.34 ~s~ony of R. James Wool:;ey, Feb. 24, 1993, op. cit., footnote 15.

Chapter 4-Technical Aspects of Nuclear Proliferation 1135The reports of nuclear smuggling out of the niumformer Soviet Union, even though most areprobably hoaxes, illustrate an important newaspect of the proliferation problem. First, they addsubstantial amounts of ‘‘noise’ to the system,making it more difficult to distinguish realproliferation threats from false ones. Second, bytheir very existence, they demonstrate the willingcomplicity of supply-side middlemen with covertchannels in the former Soviet Union, The potentialfor nuclear smuggling has thus become animportant issue.In addition to the threat of diversion ofex-Soviet weapon material from stockpiles thatare nominally under Russian military control,other material might be available from civilnuclear facilities within Russia, or from active ormothballed facilities in other republics. 35 As anNPT nuclear-weapon state, Russia is not subjectto mandatory safeguards at any of its nuclearfacilities, and several of the former Soviet republicshave not yet joined the NPT 36The issues presented by Russian plutoniumfrom dismantled weapons are quite different fromthose surrounding Russian weapon HEU. TheUnited States is negotiating the purchase of 500tonnes of Russian HEU over the next 20 years foruse in commercial power reactors. (The HEUwould be blended down to LEU in Russia beforethe material was transferred.) No comparablepurchases are envisioned for weapon-grade plutonium,making it possible that Russia wouldchoose to recycle its excess plutonium as MOX inits own power reactors or to keep as many as10,000 to 20,000 plutonium pits (the nuclearweapon cores that contain the fissile material) inlong-term retrievable storage. 37 Both the pluto-and the HEU could conceivably end up inthe wrong hands unless adequate measures aretaken to regulate their transport, storage, andultimate disposition. Procedures are required tominimize and safeguard stockpiles of both plutoniumand HEU, to use them in commercial fuel or,in the case of plutonium, to dispose of it in safeand acceptable ways, all while taking into accountstrong economic pressures and potential politicalinstability.HEU FROM RESEARCH REACTORSOver 100 of the approximatelyworldwide research and test reactors325 totalare fueledwith highly enriched uranium (HEU enriched tomore than 20 percent uranium-235), for which thetotal HEU inventory is about 4,000 kg. Most ofthis HEU inventory is in the form of 90 to 93percent uranium-235. Thirty-six HEU-fueled researchand test reactors are in the United States,some 2 dozen are in Russia and other formerSoviet republics, and the remainder are located inabout 34 additional countries. Approximately 40of these foreign reactors (not including those inthe former Soviet Union) are rated at over 1MW(t), and many contain several kilograms ofHEU fuel. 38The United States is one of the principalsuppliers of research-reactor fuel, exporting 100to 150 kg HEU annually. To reduce the proliferationrisks posed by HEU reactors, the UnitedStates has developed and tested several types ofcompatible high-density LEU fuels that can besubstituted for HEU fuels in research reactors. Allbut 3 of the ca. 40 foreign HEU-fueled researchreactors larger than 1 MW(t) could be convertedto LEU fuels developed so far, but only about 1035 w~lm c. potter, Eve E, cohe,~ and Edward V. Kayulcov, Nuclear Projiles of the Soviet Successor Srutes, Monograph No. I (Monterey,CA: Program for Nonproliferation Studies, Monterey Institute of tntemational Studies, May 1993j; and Oleg 13ukharin, The Threat of NuclearTerron”sm. . . . op. cit., footnote 12, pp. 4-5.36 As of Novem&r 1993, only ~efi~ ~e~b~jq Bel~s, Estofi, ~tvia, Li~u~a, Russi~ md UZbekiSm Md joined the ~.37 See us, confle~~, Office of Te~hnolo~ Assessment, Dismantling the Bo~ a~Managing the Nuclear Materials, op. Cit., fOOtIIOte 26,38 Milton M. Hoenig, ‘ ‘Eliminating Bomb-Grade Uranium Fuel from Researeh Reaetors,” Nuclear Control Institute, January 1991, p. 3;and Oleg BukharirL The Threat of Nuclear Terron”sm. . ., op. cit., footnote 12, p. 5.

136 I Technologies Underlying Weapons of Mass Destruction(a) During a U.N. inspection in October 1991, IAEAinspectors examine the bomb damage to the IRT-5000research reactor at Al-Tuwaitha.have plans to do so. Only a handful of otherresearch reactors have been converted so far.(Reactors operating at less than 1 MW(t) generallyhave lifetime cores, providing little incentiveto convert. )39Although all the HEU used in non-nuclearweapon-statereactors is obtained from suppliersthat require it to be placed under IAEA safeguards,a nation or terrorist group would havelittle difficulty in recovering HEU metal fromfresh fuel if it were seized from storage at thereactor site or in transit. 40 Even if the fuel werelightly irradiated, e.g., for a few hours per week atless than 100 kW (e.g., in a typical universityresearch reactor), the small quantities of radioactivefission products it would contain would notprevent recovery of the uranium, especially afterwaiting a few days or weeks for the fuel’s activityto decay to lower levels. 41(b) The Tammuz-2 reactor was also damaged bycoalition bombing during Operation Desert Storm.Both reactors had been fueled by highly enricheduranium.Most research-reactor fuel, however, has beenirradiated for longer than this, making it muchmore radioactive and difficult to handle. Theft ofsuch fuel (though likely to be regarded as a veryserious incident), would also be an unlikelymeans of acquiring a nuclear arsenal, sincequantities are limited in any one location and, inmost reactors, are significantly less than what isneeded for a weapon. Although crossing thenuclear threshold by obtaining material for evenone bomb poses a significant danger, it is not asserious a threat as assembling a production linefor making nuclear weapons in quantity. For thesereasons, the proliferation concerns involvingdiversion or theft of HEU research-reactor fuelare legitimate, but limited in scale. 42| Indigenous Production of MaterialsThe alternative to stealing, diverting, or purchasingweapon-grade nuclear materials is manu-39 Hoenig, ‘ ‘Elimi.natingBomb-Grade Uranium Fuel. . .,” ibid., p. 3; see also Armando Travelli, “The RERTR Program: A Status Repofi’Argonne National Laborato~, Oct. 2, 1992,40 For ~~ce, even before hq was discovered to have a massive nuclear weapon prograrIL there was concern tit it m.@t hve divdfor nuclear weapon use the 12,3 kg of 93% HEU originally supplied by France for its 40 MW(t) Osirak reactor or the 13.6 kg of Soviet-supplied80!Z0 enriched fuel. (See foomote 5 in box 4-D.)41 Hoenig, ‘ ‘El iminating Bomb Oracle Uranium Fuel. . ,,” op. cit., foomote 38, p. 3.42 Res~h reacto~ CaII alSO be used to produce plutonium, however, which is also a concern. see below.

— .-Chapter 4-Technical Aspects of Nuclear Proliferation | 137facturing them indigenously. Many different approachesto producing nuclear materials areavailable, depending on what nuclear materials aproliferant starts with, what access it has todual-use or nuclear-specific technologies, andwhat cost it is willing to bear to acquire proscribedtechnologies on the black market. Variousapproaches also place specific demands on aproliferant’s technology base, infrastructure, andexpertise, and pose different operational difficultiesand risks of detection once acquired.International nonproliferation policies havemade it quite difficult to use turn-key importedfacilities to produce weapon-grade materials. TheNuclear Non-Proliferation Treaty prohibits NPTparties from exporting major nuclear facilities—especially those for uranium enrichment or reprocessing-unlessthey are placed under IAEAsafeguards. (Those goods requiring the impositionof safeguards have been placed on a multilaterallyagreed ‘‘trigger list.”) In April 1992, all27 members of the Nuclear Suppliers Group(NSG) further agreed to require full-scope safeguards-theimposition of IAEA safeguards notonly on the transferred facility but also on allother nuclear facilities in the recipient country—as condition of any significant new nuclearexports to nonweapon states. NSG countries alsoadopted stringent licensing and export policiesfor a new list of 65 categories of dual-use items(see app. 4-D). However, several nations experiencedin nuclear technology-including Argentina,Brazil, China, India, and Ukraine-are notmembers of the NSG, though at least Argentinahas stated that it would abide by the original 1977NSG export guidelines.Material production could involve obtainingLEU and enriching it further to produce HEU, orit could require creating the entire nuclear fuelcycle indigenously, starting with uranium ore andending up with plutonium (see table 4-l).ACQUISITION OF NATURAL URANIUMProduction of either weapon-grade uranium orplutonium starts with uranium ore, followed by anumber of processing stages that are describedbelow. As the materials approach weapon grade,their processing facilities become more specialized,and international controls on their use andshipment become more stringent.Uranium ore, which is commonly mined alongwith other mineral-bearing ores and contains onlyabout 1 part in 500 of uranium, is not subject tosafeguards. Similarly, milling facilities that extractthe uranium concentrate known as “yellowcake”(U 30 8) from ore are not safeguarded. (Theamounts of yellowcake exported or imported byNPT states having formal safeguards agreementsin force must be reported to the IAEA, but suchtransfers are not verified by inspections. In thepast, various countries have reportedly attemptedto acquire yellowcake clandestinely. 43 ) Miningand milling processes suitable for extractinguranium concentrate are standard in the miningindustry. Many countries that are or had been ofproliferation concern have large indigenous depositsof uranium-bearing ore and already operatemines and milling facilities. 44Yellowcake effectively becomes subject tosafeguards inspections only after it is introducedinto a declared conversion plant that produces aform of uranium suitable for further enrichment(e.g., uranium hexafluoride) or for fuel fabrication43 For ~xwple, Israel is ~dely ~fieved to have orchestrated the disappearance h November 1968 of 200 tom of ye~owc*e tit was ~bshipped from Antwerp to Genoa (Spector, Nuclear Ambitions, op. cit., footnote 16, p. 155). Between 1978 and 1980, Pakistan is believed tohave acquired from Libya quantities of up to 100 tons of yellowcake that Libya had originally purchased from Niger. (John J. FiidQ “Westconcerned by Signs of Libyan-Pakistan A-Effort, ” Washington Star, Nov. 25, 1979; and Spector, Nuclear Ambitions, op. cit., footnote 16,p. 176.) Although Libya had been a member of the NPT since 1975, it was not required to report its imports or exports of yellowcake until itconcluded a formal safeg-wuds agreement with the IAEA in 1980.44 See Uranium Re~ource~, Pro~uc~on, ~n~ De~~, a Jofit Repofi of tie OE~ Nucle~ Enmgy Agency ~d the ~ (P*: OECD,1986), and other references cited in Spector, IVucZear Ambitions, op. cit., footnote 16.

138 I Technologies Underlying Weapons of Mass Destruction(e.g., oxide, metal, alloy, or carbide). Such furtherprocessing typically uses specialized facilitiesthat would trigger the application of IAEAsafeguards if imported; to evade safeguards at thisstage, a proliferant would have to construct aclandestine conversion facility with uncontrolledgoods. Doing so would add expense and effort butwould probably not introduce particular roadblocks.45PLUTONIUM PRODUCTION AND REPROCESSINGFACILITIESA key step in pursuing the plutonium route isobtaining a source of irradiated uranium, either bydiverting spent fuel from a safeguarded reactor orby irradiating uranium in a dedicated plutoniumproductionreactor. The reactors most commonlyused commercially, called “light-water reactors,’ are difficult to divert fuel from clandestinely,since their fuel rods are readily accountedfor (if safeguarded), and since shutting suchreactors down for refueling creates an observableevent (even when unsafeguarded). Moreover,they require enriched uranium to operate, whichis much more difficult to obtain outside ofsafeguards than is natural uranium.Rather than divert fuel from a safeguardedreactor, a proliferant might build a dedicatedplutonium-production reactor fueled by naturaluranium. The section below discuses costs fortwo possibilities: a small (30 MW thermal output)reactor based on a widely available design thatcould produce sufficient plutonium for 1 or 2weapons per year, and a larger (400 MW thermal)reactor that could produce some 10 to 20 weaponsworthof plutonium annually. Such productionreactors would be based on reactor technologiesbetter suited to plutonium production than is thelight-water design, but these alternate technologiestypically require specialized materials suchas heavy water or ultra-pure graphite which, ifimported, would trigger the imposition of safeguards.46 AS is also discussed below, the constructionand operation of a nuclear reactor produces anumber of indicators or signatures that mightreveal its existence (see section on monitoring).The combination of a nuclear reactor andreprocessing plant offers a potentially less technologicallyadvanced route to weapon-usablematerial than many methods of uranium enrichment.Israel and India, for instance, operateunsafeguarded reactors and reprocessing facilitiesthat, in part, were built indigenously, andNorth Korea has built and operated similarfacilities that were initially outside of safeguards.47Extracting plutonium from spent fuel utilizeschemical processes that, in theory, have beenwithin the grasp of most middle industrial powersfor some time (see table 4-2). The principaldifficulties in building a reprocessing plant stemfrom the intense radioactivity of the spent fuel tobe reprocessed. Remote-handling equipment, radiationshielding, and other specialized equipmentmust be built and maintained to protect plantworkers. Although most of the chemicals used ina reprocessing plant are available commercially,much of the needed equipment is exportcontrolled,and many countries would be unableto build such facilities without foreign technicalassistance. Large facilities have notoriously takena very long time to construct, and for technical as45 Fuel fab~~tion and cladding, for example, might be done in a common metalworking shop.46 Molec~es of heavy water have tieir two hydrogen atoms replaced by deuterium atoms, an isotope of hydrogen hving ~ extra nm~nin the nucleus. Although present in small quantities in naturally occurring water, heavy water is a controlled nuclear-related material onceconcentrated. Heavy-water and ultra-pure graphite are effective neutron moderators having very low neutron absorption thus permittingreactors to operate on natural uranium both materials are on the IAEA “trigger list’ of nuclear goods that cannot be exported by anNPT-member state without the imposition of safeguards. However, it may be possible to manufacture such graphite indigenously or to obtainnonreactor-grade graphite commercially that could be used in reactors (possibly after additional puritlcation) without triggering safeguards.47 SFtor, Nuc/ear A~itions, op. cit., footnote 16, pp. 86, 139, 172 In the 1960s, however, Mia benefited fmm shed U.S. t~hnologyand Israel obtained signitlcant technicaJ assistance from France.

Chapter 4-Technical Aspects of Nuclear Proliferation | 139Table 4-2—Reprocessing Programs and Capability Outside the Declared Nuclear Weapon StatesCapacity(actual or projected)Country Reprocessing facility Dates of operation [t HM/yr] a Safeguards?Japan Tokai-mura 1981 -present yesRokkasho-mura 2005? [800] yesGermany Karlsruhe 1971-1990 35 yesBelgium Eurochemic-Mol 1966-1974 30 yesIsrael Dimona 1966? - [50-100]? noIndia Trombay 1966-1974; [1983-present]? 30 noTarapur 1982-present 100 partlyKalpakkam 1 993/94 [200]? noPakistan Chashma construction ended 1978? [100] NARawalpindi not operating? [5]? noNorth Korea Yongbyon [1992]? pilot-scale? [yes] bIraq Tuwaitha 1989-1991 (destroyed) lab-scale (violation)South Africa Pelindaba [1987-?] pilot-scale? yes cArgentina Ezeiza suspended 1990 [5] partlyBrazil Resende suspended 1980s [3] yesSouth Korea NA abandoned 70s NATaiwan NA abandoned 70s NAa Tonnes heavy metal per year. Items in [brackets] or with question marks represent estimates or SUbStanhl unCert~nty, respectively.b Although North Korea b~ame a member of th e NpT in 1985, its safeguar~ agreement with the IAW was not signed until 1992, and theimplementation of this agreement was still under negotiation as of November 1993.C Prior to South Affi@ls joining the NPT in 1991, this facility was only under safeguar~ when safeguarded fuel was present. SirlCe then, it has COmOunder full-scope safeguards.SOURCE: Adapted from David Albright, Frans Berkhout, and William Walker, Wbrid /rwentory of P/ufonium and High/y Ervkhed Uranium, 1992(Oxford: Otiord Universit y Press/Sl PRI, 1993), p. 90; and Leonard S. Spector and Jacqueline R. Smith, Nuc/earArnbMons: The Spread of NuclearWeapons, 1989-1990 (Boulder, CO: Westview Press, 1990).well as economic and political reasons, even the countries harboring suspect facilities when theirsmaller ones are sometimes abandoned before existence is known.completion. 48 Furthermore, the IAEA and U.N. France, the U. K., and Japan, which eachinvolvement and the ongoing negotiations with operate commercial reprocessing facilities, areNorth Korea aimed at resolving the dispute over not current nuclear proliferation concerns. 49its nuclear facilities have demonstrated the kind France and the U.K. are already nuclear weaponof pressure that can be brought to bear on states, and Japan, as a non-nuclear-weapon NPTAS For ~xmple, com~ctlon on a ltige ~pr~essing facility was begun in Pakistan in the late 1970s with French assis~ce, but may havebeen abandoned sometime following France’s termination of its involvement in 1978. In 1990, Argentina also indeftitely suspended its workon building a small reprocessing plant at Ezeiza. See Spector, Nuclear Ambitions, op. cit., footnote 16, pp. 115, 239.@ ~dia, o ntie o~er hand, operates a medium-size reprocessing facility at Tarapur that is not under fU~-titOe MfegUMdS, thus ~owing itthe option of producing weapon materials free of international legal constraints if it so chose. Russia continues to operate three reprocessingplants, but in the past hm not segregated civilian from military operation. States that once reprocessed civilian spent fuel but have discontinueddoing so include Germany, Belgium, and the United States.

140 I Technologies Underlying Weapons of Mass DestructionUnder IAEA supervision in October 1991, Iraqiworkers pour concrete into glove boxes at Al Tuwaithato prevent their future use. Glove boxes are used toprotect workers from radioactive materials such asplutonium,member, has all its facilities under full-scopeIAEA safeguards. Even so, material-accountancyat large spent-fuel reprocessing plantsinvolves inherent uncertainties that are notnecessarily less than an IAEA-defined significantquantity of nuclear material.In addition, plutonium fuel-fabrication facilitiesare also now operating in France, the U.K.,Japan, Belgium, and Germany, and another onemay soon be constructed in Chelyabinsk, Russia.Plutonium and uranium recycling policies inthese countries, however, are still undergoingrevision and may not be finalized for some years(see table 4-3).URANIUM ENRICHMENT TECHNOLOGIESTable 4-4 compares various enrichment technologiesaccording to several factors that aproliferant country would have to consider beforechoosing to pursue a particular enrichment method.(See app. 4-B for descriptions of these enrichmenttechnologies.) In addition to various characteristicsof each method, a proliferant’s choice willdepend strongly upon its own technical infrastructure,expertise, and access to foreign technicalassistance. For instance, Argentina’s experiencein metallurgy was likely an important factorin its decision to pursue gaseous diffusion, andPakistan’s theft of Dutch centrifuge designs wasundoubtable influential in its decision to pursuethat approach.Table 4-5 concentrates on technical attributesof each process, comparing various enrichmenttechniques in terms of efficiency and separationfactor per stage (and thus the number of stagesrequired to enrich uranium to, say, 90 percentU-235). Each stage of an enrichment plant takesan input source of uranium, or ‘‘ feed,’ andproduces two outputs: one with a greater concentrationof uranium-235 than the feed (the “product”),and the other depleted in uranium-235 (the“tails”). The separation factor indicates howmuch enrichment each stage provides. (It isdefined as the ratio of the relative isotopicabundance of uranium-235 in the product to thatin the tails.) Some approaches, such as electromagneticseparation, achieve very high degrees ofseparation per stage, and very few stages areneeded to obtain highly enriched uranium. Others,however, only marginally enrich the productin each stage, and up to thousands of stages areneeded to obtain HEU.For enrichment approaches in which each stageprovides only marginal enrichment and thusmany successive stages are required, the stagesare connected into cascades. Each stage (usuallyconsisting of many individual elements workingin parallel) feeds its product to the stage operatingat the next higher level of enrichment and its tailsto the next lower.Table 4-5 also gives estimates for the amountof electricity per unit enrichment capacity requiredfor each approach, with enrichment capac-

.—Chapter 4-TechnicaI Aspects of Nuclear Proliferation | 141Table 4-3-Plutonium and Uranium Recycle Policies in Europe and JapanReprocessedCountry Plutonium recycle uranium recycle LWR-MOX programBelgiumFranceGermanyItalyJapanNetherlandsRussiaSpainSwitzerlandUnited KingdomYes?YesYesNo’YesYes dExpectedNoYesNoTested with MOXNo?NoYesNo?YesMOX fabricator. Plans to load two reactors withMOX, beginning mid- 1990s.MOX fabricator. First phase (eight reactors) to beloaded with MOX by 1993.16 reactors to be loadedby late 1990s,MOX fabricator. Leader in MOX experience. 18reactors to be loaded with MOX. bNo operating reactors.MOX fabricator. Demonstration program (two reactors)planned for 1994-1997. Commercial programdue to start in 1995, rising to 12 LWRs loaded withMOX by 2003.MOX R&D at Dodewaard was suspended as of1992.Uranium separated from VVER-reactor fuel is recycledin graphite-moderated (RBMK) reactors.No.Has loaded two reactors with MOX.Plans to become a MOX fabricator,a offi~al FreNh policy is to recycle uranium recovered from rep recessed spent fuel, either by m-enriching It or by using it as the matrix for LWR-MOX fuel fabrication. However, the low prlee of natural uranium has meant that the Eleetrieitd de France has shown little practical interest in uraniumrecycle.b AS of 1992, on~ IO re~tors had been awarded licenses to load MOX fuel, and MOX had been loaded at 7 of them.C A small MOx txt Progrm ~n at Garfgl~no in the 197*. Most ~alian separated plutonium h= been US4 tO fuel France’s fSSt &eeder WSCtOr,Superph&ix.d Asmai[ MO)(test Prwrm ran at ~W~rd in the 197& and l~s, Dut& separated pl~onium has ken USed h the Superphenix and Kalkarfast reactor cares.SOURCE: Frans Berkhout et al., “Disposition of Separated Plutonium,” Sa”eme & Global Security, vol. 3, No. 1, 1992, p. 14.obtain on the open market. Nevertheless, somehave escaped these controls, mainly due to laxenforcement and variability of regulations amongsupplier countries. For example, security leaks inthe URENCO consortium-a uranium enrich-ment enterprise established by the British, Ger-ity measured in terms of ‘separative work units,or SWUs. 50Most of the sensitive technologies and componentsused for uranium enrichment fall understrict export controls, both in the United Statesand abroad, and are therefore very difficult tom Sws me=~e tie d~r~ irl en~opy, or COIIVCmWly the increase in order, resulting when a giv~ iSOtOpiC fiture k Spht ~to twomixtures of greater and lesser CQncedmtions. (Combining two pure substances--say pure uranium-235 and pure uranium-238-results in amixture that is more disordered than its original constituents. Reversing that process by separating an isotopic mixture into its constituent partstherefore increases its order.)Although the exact formula relating the number of SWUS to the concentration of uranium-235 in the fee~ product, and tails is complicated,a rough appro ximation for the SWUS needed to produce a given amount of 3% or higher enriched product from natural uranium (with typicaltail depletions of about 0.3Yo) is about 12@200 timca the number of kilograms uranium-235 contained in that product. The low end of this rangeapplies to fii enrichments from 3 to 5%, the high end for those from 20 to 97Y0 (see Alkm S. Krass et al., Uranium Enn

142 I Technologies Underlying Weapons of Mass DestructionTable 4-4-Relative Ease of Developing Various Enrichment Technologies for Weapon ProgramsDiff Cent Aero Chem EMIS lC/PC AVLIS MLIS LAPAvailability factors:Technology/know-how widespread + ++ +/- +1- ++ +1-Components attainable+ .+/- +/- ++Operational factors:Convertible LEU to HEUMinimal training requiredUses standard UF 6feedLow maintenance requirementsDetectability factors:Small plant sizeShort equilibrium timeLow power consumptionCommercially justifiableOverall proliferation++++1-----+++++++++++++. .++++--+1-?+++--+1-+.---+-.+++?++?. .+/- ++ +/- + + .-+/-KEY:+/++ Indicate favorable/very favorable factor from the perspective of a potential proliferant.-/- indicate unfavorablelvery unfavorable factor.? indicates insufficient information.Diff - Gaseous diffusionCent = Gas centrifugeAero - Aerodynamic methods (Becker nozzle or Helikon processes)Chem = Chemical exchange (Japanese Asahi or French Chemex processes). .++++??.+? .-. . .+ +EMIS - Electromagnetic Isotope Separation (e.g., calutrons)iC - ion Cyclotron ResonancePC - Plasma CentrifugeAVLIS - Atomic Vapor Laser Isotopo SeparationMLIS = Molecular Laser Isotope SeparationLAP - kser-Assisted Process (e.g., Chemical Reaction by Isotopic Selective Laser Activation, or CRISLA)a The ion~xchange resin developed anct used in Japan by the Asahi Chemical Co. is proprietary and would be difficult tO dupiicate, even if -rnplescould be obtained. However, a number of research programs around the world are developing fast equilibrium-time resins that might be useful forfuture chemicai enrichment applications. it has also been reported that Ukraine produces an ion-exchange resin simiiarto that used in Japan’sAsahi process (William C. Potter, Monterey Institute of International Studies, private communication, November 1992).b overall Proliferation ~ncern shoui,~ be taken only as a very rough indicator, since it is strong/y cOunfrydependant. In arriVing at thk ov-11 mting,“availability” and “operational” factors were each given twice the weight of the “detectability” factors, but forcx)untrfeswtth an advanced technologybase or skiils suited to a particular technology, the relative weighting might be very different.SOURCE: AlIan S, Krass et al., Uranium Enrichment and Nuc/ear Weapon Proliferation (London: Taylor a Frands, Ltd., 1983), p. 19; Marvin Millerand George Rathjens, “Advanced Tecl-moiogies and Nuclear Proliferation,“ in Robert H. Bruce, ad., Nuclear Proliferation: South Aaiaandthe Mkk9eEast, Monograph No. 2 (Perth, Australia: Indian Ocean Center for Peace Studies, 1992), pp. 107-123; and OTA (see app. 4-B on enrichmenttechnologies).+++?-?+?

Chapter 4-Technical Aspects of Nuclear Proliferation 1143Table 4-5—Efficiency of Uranium Enrichment Technologies aSeparation factor or No. of stages kW forenrichment factor b for 90% HEU C kWh/SWU 4,000 SWU/yr3,500-4,000Gaseous diffusion. . . . . . . . . . . . 1.004-1.0045LAP (CRISLA). . . . . . . . . . . . . . ~` [1.5] g - [20]Gas centrifuge. . . . . . . . . . . . . . . 1.2-1 .5 d40-90AerodynamicHelikon/UCOR. . . . . . . . . . . . . . 1.030540Becker nozzle. . . . . . . . . . . . . . 1.0151100ChemicalFrench Chemex. . . . . . . . . . . . . 1.002-1.003Japanese Asahi. ., . . . . . . . . . , 1.001-1.00135,000-8,000’12,000-1 6,000’Electromagnetic bEMIS (calutron). . . . . . . . . . . . . 20-402-3ion cyclotron resonance/Plasma centrifuge. . . . . . . . . . . - [3-10][4-8]Laser processesAVLIS. . . . . . . . . . . . . . . . . . . . . - [5-1 5][a few]MLIS. . . . . . . . . . . . . . . . . . . . . , - [3-1 o?][under 10?]2,500100-2004,0003,60060015020,000 -30,000 f[200-600][100-200][200-250][tens?]1,20050-1002,0001,8003007510,000-15,000[100-300][50-100][100-125][low]a Estimates in [brackets] are uncertain and may not be achievable on an industrial -le.b For electromagnetic and I=er ~rwe~e~, estimates are for the enn’chmenf factor, not the separation factor. “Separationfactor” is defined as the ratio of the relative (235U-to-2wU) enrichment of the product to that of the tails in any one stage of acascade, and is the figure given for diffusion, centrifuge, aerodynamic and chemical processes. “Enrichment factor” is the ratioof relative enrichment of the product to that of the bed, which is more relevant to processes whose separation per stage is highenough that a many-stage cascade is not required, and in which the “cut” (the ratio of the total amount of material in the productto that in the tails) is therefore not as relevant. The separation factor for a given process is always larger than its enrichmentfactor, but only slightly larger when the cut is much less than 50’Yo, as it may be in some laser processes.C Assumes tails with 0.3’%. Z35U COllhlt.d The given range applies t. m~ern centrifuges and is dependent on their length, rotational speed, and other f=tors. The eafliestcentrifuges operated at subcritical peripheral speeds of 250 m/see and had separation factors of only 1.026. See MansonBenedict and Thomas H. Pig ford, Nuclear Chemical Engineering, 2nd ed. (New York, NY; McGraw-Hill, 1989), chapter 12.e For Chemiml Prmesses, a single physi~l item (e.g., an ion exchanger or pulse COIUmn) an ~nt~n tens or hundr~s ofeffective “stages, ” so that these large numbers can be misleading.f This figure is sometimes given as 3,000-4,000 (e.g., see Kr~s et al., below, p. 189), Whkh would app~ onty to significantlyimproved calutrons that used multiple beams, permanent magnets, or other refinements. The figure given in the table is basedon U.S. “Alpha” machines used during the Manhattan Project, which produced only about 1/3 gram uranium-235 per machineper day in about a 200/0 enriched product, and used more than 50 kW per machine to power the electromagnets, pumps, andion beams.9 Estimate from Marvin Miller; derived from prelim inary 1986 data of Isotope Technology, a small west-coast firm promoting theCRISLA process.SOURCE: Adapted by OTA from U.S. Department of Energy, Nuclear Proliferation and Civilian Nuclear Power, Report of theNonproliferation A/temative Systems Assessment Program (NASAP), “Volume il: Proliferation Resistance,” DOE/NE-0001/2,June 1980, p. 3-7; AlIan S. Krass et al., Uranium Emichment and Nuclear Weapon Proliferation (London: Taylor & Francis, Ltd.,1983), p. 188; and Marvin Miller, “Atomic Vapor Laser isotope Separation,” FY1989 Arms Control Impact Statements,(Washington, DC: U.S. Government Printing Office, April 1988), p. 142.

144 I Technologies Underlying Weapons of Mass Destructionman, and Dutch governments-have contributedto the proliferation of its centrifuge designtechnology.Some components of very old technologies,such as electromagnetic isotope separators (EMIS,also known as “calutrons’ ‘), and of very newtechnologies-some of which have still not beendeveloped to a commercial scale by even the mostadvanced industrialized countries-have not beensubject to export controls. 51 For example, magnetsand beam sources for EMIS, and some lasersthat could be used for laser isotope-separationtechniques, have such widespread commercialapplications that they have not been controlled inthe past. 52Although gaseous diffusion dominated Westerncommercial enrichment for over three decades,it is now being overtaken by gas centrifugetechnology. Neither technique has yet been usedoutside the five acknowledged nuclear powers toproduce HEU on a large scale. However, theproliferation potential of centrifuges has wonconsiderable attention both because of Iraq’spursuit of the technology before the Gulf War andbecause of Pakistan’s success at building its ownmodem gas centrifuge plant with the help ofblueprints and purchase orders stolen from theDutch factory of the URENCO consortium. 53Detailed information on older centrifuge technology,in fact, is available in published documents.54 However, these comparatively rudimentarydesigns are at least 25 times less efficient interms of energy use and separation capacity thanmodem designs, whose manufacturing processes,design parameters, and operating characteristicsremain classified. Older designs therefore cannotlead to facilities nearly as compact and efficientas those using modem technology. However, it isnow becoming known that the former SovietUnion began developing gas-centrifuge technologyon a massive scale in the 1950s and hasadvanced to fifth-generation designs. Russia continuesto operate four major gas-centrifuge enrichmentplants-though since 1987 these haveonly produced LEU for reactors—with a totalcapacity of about 10 million “separative workunits” (SWUs), about half the world’s total forthis technology .55Conversion of an existing facilityLarge commercial enrichment facilities producingLEU for nuclear power plants, ifreconfigured for higher enrichments, would51 ~ 1961, fie U*S. dec~ssfi(~ tie te.c~olo~ fo rel~~~~etic ~d ~rod@c efichment techniques, and for gaseous diffusionexcept for its diffusion barriers and pump seals. Germany found little difilculty in sharing the technology it had developed for the Becker nozzleaerodynamic process with South Ahica, which in turn went on to develop on an industrial scale a different version of the process called Helikoqor ‘‘stationary-wall” centrifuges. Although designs are also available in the open literature for early gas centrifuges, modern centrifugetechnology remains classifkd both in the U.S. and by the URENCO consortium.52 Note, however, that the new Nucleu Suppliers Guidelines for dual-use items, once implemented, wi~ tighten export COntrOk on mmyof these technologies (see app. 4-D).53 shy= BIU@ Nuclear Rivals in the Mial.ile East (1.ondon: Routledge, 1988), p. 8; James Adams, Engines of War: Merchnts of Deathand the New Arms Race (New York, NY: Atlantic Monthly Press, 1990), pp. 200-203; and Spector, Nuclear Ambitions, op. cit., footnote 16,pp. 90,97. Illicit efforts by proliferant states to obtain goods and technology have continued, as witnessed by the July 7, 1992 conviction inPhiladelphia of Pakistani General ham al-Haq for conspiring to illegally export maraging steel-350 (a materiaJ needed to construct gascentrifuges).~ See, for example, Gemot 25ippe, The Development of Short-bowl Ulrracentri@ges, University of Vir= Report No. W-442O-1O1-6OU,submitted to Physics Branch, division of Research U.S. Atomic Energy Commissio% WashingtorL DC, July 1960, referenced in Krass et al.,Uranium Enrichment. . . . op. cit., :footnote 50.55 See Mark Hibbs, NuclearFuc/, Oct. 26, 1992, p. 3; Oleg B~“ , The Threat ofNuclear Terrorism. . . . op cit., footnote 12, August 1992,p. 4; and David Ah@, Frans Berkhou~ and William Walker, World Invento~ of Plutonium and Highly Enriched Uranium, 1992 (Oxford:Oxford University Press/SIPRI, 1993), pp. 54-56. According to these sources, all Russian centrifuge plants employ subcritical, aluminum-rotorcentrifuges with annual throughput believed to be only around 5 SW per machine,

—Chapter 4-Technical Aspects of Nuclear Proliferation I 145have the enrichment capacity to make HEU fortens of weapons annually from the sameamount of uranium source material requiredeach year to fuel just one commercial-sizenuclear power plant. Furthermore, each suchenrichment facility typically supplies fuel formany tens of power reactors annually. 56If the enrichment technology is capable ofdoing so, upgrading 3 percent enriched uraniumto 90 percent enriched uranium requires onlyabout as much energy and enrichment effort aswas required to enrich the 3 percent uranium inthe first place. Although a cascade to enrich asmall amount of LEU to weapon-grade levelswould require several times as many stages asan LEU facility, each stage could be built withmany fewer or much smaller elements, and itwould cost only a fraction that of a largeenrichment facility. Therefore, if they could avoiddetection by safeguards (which would be difficult),those few countries already possessingcommercial enrichment facilities could easilyproduce substantial amounts of nuclear weaponmaterial by reconnecting part of a facility toproduce 90 percent enriched material, by secretlyadding additional enrichment stages, or by divertingsome 3 percent enriched material to another(clandestine) facility .57A covert facility fed by a small amount ofdiverted LEU, in theory, could be quite smalland difficult to detect, although safeguards aredesigned to detect the diversion of the LEU. (Seethe following section.) The difficulty of reconfiguringan existing facility without detection, asopposed to building a new one, however, dependsupon the type of enrichment technology used.Converting a large gaseous diffusion or chemicalexchangeplant without detection from low tohigher enrichments would be extremely difficult.Doing so would require either a complex reconnectionof cascade elements, the addition ofthousands of additional stages, or the reintroductionof enriched material into the original feedpoint. 58 Given the size of commercial facilities, itcould take from months to over a year tore-establish steady-state plant operation aftersuch a change, during which the change wouldalmost certainly be detected.Centrifuge cascades, on the other hand, canrelatively easily be made to produce higherenrichments-either by adjusting the feed rates,by reintroducing higher enriched material into thefeed, or by reconfiguring the cascade itself. 59Since centrifuge-cascade equilibrium times areon the order of minutes to tens of minutes, such achange in enrichment levels could be accom-56 That a commercial nuclear reactor requires far more fissile material than a nuclear weapon can be seen by comptig tiefi energy ou~uts.A 1,000 MW(e) nuclear power plant, which generates heat through fission at a rate of about 3,000 MW, releases the energy equivalent of about60 kilotons of TNT each day.Alternatively, starting with natural uraniunL less than 5,000 SWUS of enrichment effort are needed to produce an IAEA significant quantity(25 kg) of highly enriched (90 percent) uranium. In contrast, over 100,OOO SWUS are required to produce the approximately 30 tons of 3%enriched uranium consumed each year in a large commercial reactor, and commercial enrichment facilities have capacities of millions of SWUSper year.57 me On]y non.nuclW.weapon smtes actively involved in commercial enrichment for nuclear power are (SW table 4-7) Jap~ SOU~ ~ca,and those countries participating in two consortia: URENCO and Eurodif. URENCO, established in 1971 by the U. K., W. Germany, and theNetherlands, operates several large centrifuge-based enrichment plants, Eurodif, a private commercial collaboration involving France, Italy,Belgiuu SpairL and Iran that began soon thereafter, operates a large gaseous diffusion plant (10.8 million SWU/yr) at Tncastin in France. (Iranhas been excluded from active participation since the 1979 revolution.)56 Especi~ly for che~cal-eficdent methods, which employ liquid phases, reeordiguration fOr HEU could also rt@re Smaller ekmenmto avoid the possibility of criticality accidents.59 Adju5~g he f~d rates CMI increase the enrichment of tie product uP to some maximum for a given cascade, called the “total reflux’enrichment level. If normal operation of a given cascade produces 370 enriched product, then operating near total reflux could produce around12% enrichments. Krass et al., Uranium Enrz’chmenr, . . . op. cit., footnote 50, p. 116. MLIS and the South African Helikon techniques mightalso offer advantages for producing HEU, but MLIS is still in the developmental stages, and the Helikon method currently utilizes an inflexiblearchitecture. (See table 4-4 and table 4-5.)

146 | Technologies Underlying Weapons of Mass DestructionPart of a gas-centrifuge cascade operated by Japan’sPower Reactor and Nuclear Fuel DevelopmentCorporation (PNC). As required by the NPT allof Japan’s nuclear facilities come under IAEAsafeguards and are regularly inspected.plished much more rapidly than for gaseousdiffusion plants, whose: equilibrium times areweeks to months.It is unlikely that operators of existing safeguardedcentrifuge facilities would reconfigure oroperate them clandestinely to produce HEU.Nevertheless, such a reconfiguration or modifiedoperation is certainly possible and might evenelude detection if them were a several-monthperiod between safeguards inspections and if thealteration could somehow be made to look to theplant’s containment and surveillance system likeroutine maintenance. Any such reconfigurationwould require the collusion of many plant operatorsto keep it secret, however, providing a furtherdeterrent. 60Building a dedicated facilityTable 4-6 lists the specialized requirements forthe different enrichment approaches that could betaken by a potential proliferant who wished tobuild a dedicated uranium enrichment facility,indicating which are currently subject to exportcontrols. Table 4-7 presents the status of each ofthe enrichment approaches in a number of countries.Many states have conducted R&D into anumber of different approaches, with 10 non-nuclear-weaponsstates apparently having built pilotplants or production capability utilizing at leastone of these enrichment methods. In India,Pakistan, and Iraq, those facilities have not beensafeguarded, and in Brazil, Argentina, and SouthAfrica, they have only recently been placed undersafeguards.The smallest, most easily hidden enrichmentfacilities would be based on energy-efficientprocesses that achieved high levels of enrichmentin just a few stages. For example, laser andpossibly plasma separation processes would bequite valuable to a proliferant state seeking acovert enrichment facility. However, energyefficiency and high separation per stage areusually directly related to technical complexity,and these advanced techniques will probablyremain relatively inaccessible to developing countriesfor some time. Despite more than twodecades of development work on these techniques,the most technologically advanced countriesin the world have only recently taken laserseparation techniques beyond the laboratoryscaledemonstration stage. 6lAerodynamic methods such as the BeckerNozzle and Helikon process (see app. 4-B) havehigher separation factors than gaseous diffusion,enabling them to reach high enrichments withfewer stages and smaller facilities. With nomoving parts other than the compressors andpumps, they are operationally less complex than@ Moreover, u a result of the early 1980s Hexapartite Safeguards Project addressing Stiems fOr centrifuge enrichment fwilitia,countries operating the principal centrifuge facilities in Europe and Japan have agreed to the principle of limited fkquency unannounced access(LFUA) as one way of further reducing the possibility of any such reemtlguration. The Hexapartiteproject involved Australia, German Y, Jap~the Netherlands, the United States, and the United Kingdom, as well as the IAEA and Euratom.c1 South Africa’s Atomic Enew Corp., Ltd. plans to test a prototype molecular-laser-isotope-separation (MLIS) uranium enrichment-unitsometime in 1994, Note that this is in contrast to the AVLIS process currently being developed in the U. S., France, and the U.K. Franceannounced in April 1992 that it had successfully produced 10 grams of low-enriched uranium using laser enrichment.

Chapter 4-Technical Aspects of Nuclear Proliferation | 147Table 4-6-Special Requirements for Uranium Enrichment TechnologiesGaseous diffusionGas centrifugeAerodynamicChemicalEM IS (calutron)Ion cyclotronPlasma centrifugeAVLISMLIS/LAP (CRISLA)Feed MaterialUF 6gasUF 6gas4% UF 6plus96% H 2(mixture)U compoundsucl 4bU metalU metalU metalUF 6gasCritical Equipment/Technology”UF 6processing equipment (corrosion-resistant)”; diffusionbarrier”; specialized compressors/pumps/seals*; largeheat exchangers.All components”: maraging steel (or other high strength-toweightmaterials); endcaps; rotors; bellows; center posttubes; specialized ring magnets, magnetic suspensionassemblies, and bottom bearings; scoops; baffles; outercasing; drive systems such as inverters; desublimers;high temperature furnaces; UF 6processing equipment(corrosion-resistant). Also: vacuum/molecular diffusionpumps.UF 6processing equipment (corrosion-resistant)”; jet-nozzleunits’ for Becker process, or vortex unit* for Helikonprocess (which uses a 2%/98% gas mixture); compressors/pumps/seals(corrosion-resistant)”.Proprietary ion-exchange resin” and exchange catalysts* (forAsahi process), or organic solvents and avoidance ofcatalytic elements (for Chemex process).Large electromagnets; high-voltage power equipment; stable,high-current ion source; collectors; vacuum/moleculardiffusion pumps; UC1 4processing equipment; and uraniumrecycling plant.Superconducting magnets; large solenoids; ion source; liquidhelium; radiofrequency power supplies.(Same as ion cyclotron method, but excluding radiofrequencypower supplies)High-power, pulsed dye laser; copper-vapor laser; vacuumpump; uranium vaporization equipment (such as electronbeamheater); high-voltage collector power supply; refractorymaterials.High-power pulsed C0 2laser; CF 4, CO, or excimer lasers (16mm I R and/or UV); UF6carrier-gas mixture; UF 6processingequipment (corrosion-resistant)”.Thermal diffusionliquid UF 6UF 6processing equipment (corrosion-resistant)”.a Those items marked with ~terisks (*) have been regulated by export controls for many years. Many of the remaining items(subject to certain threshold specifications) will come under the new NSG dual-use exportentrol guidelines, onceimplemented by NSG countries (see app. 4-D). Note, however, that while such controls may impose signif”kant barriers toacquisition, they do not make it impossible.b Higher efficienq liquid metal ion sources might also be us~, see l/.E. Krohn, and G.R. Ringo, “tori Sources of HighBrightness Using Liquid Metal,” App/. F%ys. Letters, vol. 27 (1975), p. 479; and Oswald F. Schuette, “ElectromagneticSeparation of Isotopes,” U.S. Congress, Office of Technology Assessment, Nuclear Proliferation and Safeguards, OTA-E-48(Washington DC: U.S. Government Printing Office, June 1977), app. vol. 2, Part 2-VI*, pp. 93-108,SOURCE: Adapted by OTA from Sean Tyson, “Uranium Enrichment Technologies: Proliferation Implications,” Eye cm Supp/y(Monterey, CA: Monterey Institute for International Studies), No. 5, fall 1991, pp. 77-86,

148 I Technologies Underlying Weapons of Mass DestructionTable 4-7-Status of Uranium Enrichment Technologies by Country aDiff Cent Aero b Chem c EMIS IC PC LIS AVLIS MLIS LAPDeclared nuclear weapon states:Us. 3 2 1 1 3 1 1 2 1 1Russia 3 3 1 2 1France 3 1 2 1 1U.K. 3 3 1China $3 2 1 11Nonnuclear-weapon states under safeguards with at least pilot-scale enrichment facilities:Argentina :2 1Brazil 2 2 1 1Germany 2 3 2 1Italy 2 1 1Japan 1 3 2 1Netherlands 2,- 3 1South Africa 1 311 11Countries outside the NPT or otherwise of proliferation concern:India 2Iran “1 1Iraq ‘1 1 1 1 2Israel 1Pakistan 211NPT parties (under safeguards) with only R&D-level enrichment programs:Australia 1 1 1 1Belgium I 1Canada 1South Korea 1Romania 1Spain 1 1a Entries indi~te the highest level of development achieved by a given country baaed on Urlclaaaified sources. some p-sss m~ have beendiscontinued by some countries.b somh Afrfca has develo@ the }Ielikon aerodynamic process to industrial acale; Garmany, Brazil, and the United States have focused on theBacker nozzle.c Japan and Frame have develop~ the Asahi ion~xchange and Chemex solvent-extraction chemical pmoeeaea, reSpeCtiVdy. The Vedf@ ofother countries’ chemical-enrichment research programs are not known.KEY:1 = R&D2- Pilot Plant: facility with enrichment capacity of leas than 100,000 SWU/yr.3 = Industrial Capability: fadllty with capacity of 100,000 SWU/yr or more.LIS = Laser isotope separation techniques, general (AVLIS, MLIS, or LAP) (See key to table 4-4 for other abbreviations.)SOURCE: Adapted by OTAfrom David Aibright, Frans Berkhout, and William Walker, Mbrkf/nvenfory of/Yukm/urn and High/y Enriched Uranium,7992, (Oxford: Oxford University ProeWSiPRl, 1993); Sean Tyson, “Uranium Enrichment Techndogiea: Prolifemtion Implications,” Eye on Supply(Monterey, CA: Monterey Institute for International Studies), No. 5, fall 1991, pp. 87-88; Man S. Krasa et al., Umnium Enrfchrnent and Nuc/earWeapon Proliferation (London: Taylor & Frands, Ltd., 1983), p. 34.

Chapter 4-Technical Aspects of Nuclear Proliferation ! 149centrifuges or laser processes. 62 Though not asenergy efficient as centrifuges, aerodynamic methodscan significantly enhance their productionrates by using low-enriched uranium feed and canbe used to produce very high enrichments. 63 Theymay therefore be a proliferation concern. However,complex small-scale manufacturing technologyis required to fabricate critical aerodynamiccomponents for the Becker nozzle technology,and the Helikon process is proprietary.Therefore, countries without very sophisticatedtechnical capabilities would have to import suchcomponents (in violation of export controls).Although key aspects are proprietary, chemicalseparation techniques such as the Japanesedevelopedion-resin process and the French solventextraction method are based on conventionalchemical-engineering technology that in generalis available to a great many countries around theworld (see ch. 2). This enrichment approach couldtherefore prove difficult to control if the specificprocesses and materials involved were reproducedby a proliferant state.Gaseous diffusion was the primary enrichmenttechnique used by each of the five acknowledgednuclear powers. Classification by the UnitedStates of diffusion-barrier and compressor technologythus was not able to prevent its independentdevelopment by the other nuclear weaponstates, even as early as the 1950s and 1960s. 64Since then, however, the only other country thatappears to have had some success at developinggaseous diffusion on its own is Argentina. 65 Sinceconsiderable engineering and materials expertiseare required to design barriers and large corrosionresistantcompressors, the less-industrially advancedcountries would still find it difficult toconstruct gaseous diffusion facilities. 66 Moreover,diffusion facilities are large and energyinefficient, making them virtually impossible tohide from detection on a commercial scale.FROM NUCLEAR MATERIALS TO NUCLEARWEAPONS| Knowledge and ExpertiseAlthough successfully designing a nuclearexplosive device requires individuals with expertisein metallurgy, chemistry, physics, electronics,and explosives, the required technology datesback to the 1940s, and the basic concepts ofnuclear bombs have been widely known for sometime. Much of the relevant physics for a workabledesign is available in published sources. As theIraqis and others have discovered, many unclassifiedor declassified documents can also be obtainedthat make designing a weapon considerablyeasier than it was for the first nuclear powers(see box 4-D). 67 The first gun-type weapon ever62 me He~O~ ~rweSS ~M @ely developed intem~ly in Souti ~ca titer it pmch~~ rights to the related Becker Nozzle tdlllOIOgyfrom Germany. Brazil also invested in the Becker technology in the late 70s. See Spector, Nuclear Ambitions, op. cit., footnote 16, pp. 243,270.62 me He~on proce~~ “as lugely developd ~tem~ly in Souti ~ca titer it pmch~~ @ts to tie related Becker Nozzle t~hno]ogyfrom Germany. Brazil also invested in the Becker technology in the late 70s. See Spector, Nuclear Ambitions, op. cit., footnote 16, pp. 243,270.63 El~@o~Wetic isotope separation also has these three attributes.64s= ~bfight et al., World Invento~. . I op. cit., footnote 55, pp. 49-66.65 rbid., pp. 180-181.66 ~w, for ~wm, r~ofl~y work~ on g=eous diffusion for 6 years before abandoning it in favor of other metiods. Jay C. Davis ~dDavid Kay, “Iraq’s Secret Nuclear Weapon Program, ” Physics Toaizy, July 1992, p. 22.67 For fi~ce, -y ~sic physi~~ Pficlples of nuc]~ w~pom (~ough not tie implosion con~pt) Ue discussed in Robert Serber, TheLos Alamos Primer: First Lectures on How to Build an Atomic Bomb (Berkeley, CA: Univ. of California Press, 1992). Serber’s lectures weref~st given at Los Alamos at the start of the Manhattan Project in April 1943. Lecture notes were transcribed at the time and then declassiiledin 1965. The Iraqis legally obtained copies of many such documents from the Wesg such as declassified documents on lithium-6, a materialuseful for more advanced nuclear weapons. David Kay, head of several IAEA nuclear inspections in Iraq, private communication, Jan. 8, 1992.

150 I Technologies Underlying Weapons of Mass DestructionBox 4-D-lraq’s Design Effort and Enrichment ApproachesBefore the Gulf War, Iraqi scientists had progressed through several design iterations for a fission weaponbased on an implosion design (one that is much more difficult to develop than the alternative, gun-typedesign-see app. 4-A). Still at the early stages of completing a design, they had successfully overcome some butcertainly not all of the obstacles to a workable device. 1 Using HEU, a completed device based on the latest Iraqidesign reportedly might have weighed from about a tonne to somewhat more than a tonne. 2 The Iraqis alsopossessed flash x-ray photography equipment and high-speed streak cameras? both useful in the R&D phasefor studying the timing and compression achieved by a nuclear implosion design.How close Iraq was to completing a bomb is still open to debate. At the request of the IAEA, a group of nuclearweapon designers from the United States, Britain, France, and Russia met in April 1992 to assess the progressof Iraq’s nuclear program prior to the Persian Gulf War, based on documents that had been obtained throughsubsequent inspections. These designers reportedly concluded that bottlenecks in the program could havedelayed completion of a working bomb for at least 3 years, assuming Iraq had continued its multifaceted strategyand design approach. 4 However, several experts familiar with the inspections believe that lraq could also probably1 seepeterzrnnwr~n,’’lmq’s NudearAchlevements: Components, Sources, and Stature,” CongresdonalResearch Sertice report 93-323F, Feb. 18, 1993, pp. 18-22 and esp. app. 4-B, which reprints the A/-Atheer PlantProgress Fteporttorthe Per/od 7 January 1990t031 May 7990, Annex to the Sixth Inspection Report, U.N. SecurityCoundl S/23122, Oct. 8, 1991 (English), app. 4-B, pp. 23-24. Al Atheer was the prlndpal site for weaponizationresearch, development, and experimentation, similar to some of the roles played by lxM Atamos during theManhattan Project. The sixth inspection included the famous incident in which inspectors were detained for 4 daysin a parking lot in downtown Baghdad near Petrochemical-3 (PC-3) headquarters.2 see, for example, Zimmerman, op. at., footnote 1, p, 19; and Colin Norman, “Iraq’s Bomb Program: ASmoking Gun Emerges,” Science, vol. 254, Nov. 1, 1991, pp. 644-645.3 David Kay, head of several IAEA nudearinspections in Iraq, pdvatecommunication, MC. 1,1992. $eeatsoA/-Atheer Plant Progress Report for the Period 1 January 19W to 31 May 1990, op. dt., footnote 2, pp. 23-24.4 paul l.ewis, “U,N. Experts NOW Say Baghdad Was Far From Making an A-Bomb Before Gulf War,” *WYork T..mes, May 20,1992, p. A6. See also, David Atbright and Mark Hibbs, “Iraq’s Quest for the Nuclear Grail: WhatCan We Learn?,” Arms Control Today, vol. 22, No. 6 (Juiy/Aug 1992), p. 7.designed (the Hiroshima weapon), in fact, wasbased on such a sure--fire technique that nonuclear test was deemed necessary before it wasused in warfare. (See app. 4-A for discussion ofnuclear weapon designs.)Nevertheless, knowledge must be supplementedby industrial infrastructure and the resources tocarry a nuclear weapon program to completion.The technologies for building cars and propellerdrivenairplanes date back to early in this century,but many countries still cannot build them indigenously.The following section discusses some of thekey areas of technical expertise required toconstruct weapons once the materials have beenacquired.COMPUTER SIMULATION AND DESIGN CODESHigh-performance computers are not now,and never were, an essential technology fordesigning fairly sophisticated nuclear weapons.Various types of weapon designs weredeveloped by the United States (as well asperhaps each of the other declared nuclear powers)without any kind of electronic computer. 68m Witi o~y Vew p~itive Colnputem, tiese designers reportedly studied 1,000 physical prototypes of tie bomb before designing ~eirfust nuclear weapon. John W. IAwis and Xue Litai, China Builds the Bomb (Stanford, CA: Stanford University Press, 1988), p. 155.

Chapter 4-Technical Aspects of Nuclear Proliferation I 151have produced a workable device in as little as 6 to 24 months, had they decided to seize foreign-supplied HEUfrom under safeguards and focus their efforts on a crash program to produce a device in the shortest possibleamount of time. 5In addition to extensive development of the electromagnetic isotope separation technique (EM IS, also calledcalutrons) and preliminary work on centrifuge enrichment technology and materials acquisition, 6 Iraq had alsobeen pursuing chemical enrichment including both the ion-resin process developed by the Japanese and theliquid-liquid solvent extraction process developed by the French (see app. 4-B). At the time of the Gulf War, mostWestern analysts-with the notable exception of the French-believed that the chemical enrichment facility atTuwaitha “Building 90” was not yet operable. Subsequent inspections by the IAEA, under auspices of the U.N.Security Council Resolution 687, found lab-scale experiments in chemical enrichment, but no evidence of successor any plans for a production plant. Since the French technology is both proprietary and subject to export controls,the Iraqis reportedly resorted to clever negotiation tactics to garner considerable amounts of design informationon the process, ostensibly with the goal of licensing the technology at some point in the future. Their techniquesreportedly included pressing for more and more technical details during a contract negotiation and then breakingoff discussions just before closing a deal. 75 In April 1991, Iraq’s inventory of safeguarded highly enriched uranium included Unirradiated fuel in theamounts of 13.6 kg of Soviet-supplied 80%-enriched HEU plus under 0.5 kg (out of the original 12.3 kg) ofFrench-supplied 93% HEU; plus partia//y irradiated fuel in the amounts of 3.6 kg of 809’o and 11.8 kg of 93°\0.Additional 80%-enriched HEU was listed as irradia@d (fissile material would have been difficult to extract quicklyfrom the irradiated fuel). Johan Molander, U.N. Special Commission, quoted in “Iraq’s Bomb Program: A SmokingGun Emerges,” op. cit., footnote 2, p. 254.6 nese aspects of the Iraqi program have all subsequently been described in SO~ depth in publishedarticles and reports. See, for example, Zimmerman, “Iraq’s Nuclear Achievements. . .,” op. cit., footnote 1.7 David Kay, presentation atthe National Institute of Standards and Technology (N IST), Gaithersburg, MD,May 15, 1992.Moreover, most of the U.S. nuclear weaponsdeveloped through the mid- 1970s were designedwith computers no more capable than a typical1990 engineering workstation—i.e., 1,000 to100,000 times less powerful than modem highperformancecomputers, which now perform wellin excess of 1,000 MFLOPS (million floatingpointoperations per second); 69 these weaponsincluded high-efficiency primaries and the firstthermonuclear weapon (1950-55); smalldiameterprimaries and nuclear artillery (1955 -60); small strategic warheads (1960-65); thewarhead for the Spartan antiballistic missile(1965-70); and weapons with tailored outputs(1970-75). 70 Of course, U.S. designers had thebenefit of an extensive series of nuclear tests,which allowed them to validate both the weaponsthemselves and the computer programs thathelped design them. 71Records obtained during the sixth IAEA inspectionin Iraq show that the Iraqis had developedor acquired a number of computer codes for69 A ~ic~ ‘‘ supercomputer’ of the mid- 1980s, such as the CRAY X-MP, had a speed of about 100 MFLOPS. Jack Worltou LaboratoryFellow, Los Alamos National Laboratory, “Some Myths about High-Pcrfo rmance Computers and Their Role in the Design of NuclearWeapons,” Worlton & Associates, ~chnical Report No. 32, June 22, 1990.‘lCI U.S. llepment of Energy, “The Need for Supercomputers in Nuclear Weapons Design, ” January 1986 (declassified), as cited inWorlton, ibid.71 ~vmc~ Computation] ~wa in tie United States ~s also ~eatly facilitated mifia~fig nuclea weapons (i.e., achieving higheryield-to-weight ratios) and minimizing the amount of nuclear material they use. Moreover, it has promoted the development of ‘safer’ (lesslikely to detomte or disperse plutonium accidentally) and “cleaner” (for example, thermonuclear) weapons, and weapons that are designedto be reliable after being deployed for several decades.

152 I Technologies Underlying Weapons of Mass Destructionuse in their nuclear weapon design effort. Thesecodes, found by IAEA inspectors, had beenrunning on IBM PS/2 desktop computers; 72 suchmachines are capable of assisting with the designof first-generation nuclear weapons.Since minicomputers, professional workstations,and other advanced computers roughlydouble in performance every 1 to 2 years,many types of computer become availableworldwide not long after they are introduced,as they fall behind the rapidly advancingstate of the art. Companies not subject toU.S.-style export controls—for example, in Israel,Brazil, India, and Bulgaria-are now developingand assembling indigenous high-performance computers comparable to or exceeding thebest U.S. computers of just 5 or 6 years ago. Aproliferant could also increase his computationalpower without violating export controls by installingaccelerator boards for low-end to midrangecomputers or by dedicating a relativelyhigh-level machine (which is usually shared bymany users simultaneously) to a single designeffort. 73Therefore, top-of-the-line computers and numericalcodes are certainly not a prerequisite to asuccessful nuclear weapon program, though theirimport may serve as an indicator of such andthereby provide valuable intelligence information.Given the utility of widely availablecomputers to a weapon designer, even verystrict export controls on top-model computerswould probably do little to slow the developmentof a first-generation weapon program.Computational power would be relatively moreimportant for programs pursuing advanced nuclearweapons, including thermonuclear ones.NUCLEAR TESTING AND WEAPON FABRICATIONAlthough extensive testing of the implosionsystem and other weapon components wouldnormally be essential before settling on a nuclearimplosion design, nuclear testing (at full or nearlyfull yield) would not be required to field fissionweapons, even for a new nuclear proliferant (seebox 4-E). Both “hydrodynamic” tests of implosioncharacteristics (using a nonfissile core) and“hydronuclear” tests with extremely low nuclearyield can be used to lessen the need for full-scalenuclear tests in determining the adequacy of animplosion design. 74 Gun-type devices have evenless demanding test requirements. If a proliferantstate with competent designers decided inadvance that no nuclear tests were to becarried out, it could pursue designs for fissionweapons in the absence of those tests thatwould have a high probability of producingsignificant yields. Testing would be much moreimportant, however, for a proliferant to developeither very low-weight nuclear weaponsor thermonuclear weapons.Weapon fabrication would also probably notpresent major technical hurdles to a proliferant.Assembly of a gun-type weapon is relativelystraightforward. Implosion-designs would requirelathes, other machine tools, and possibly isostaticpresses to fabricate explosive lenses and othercomponents, but there may be several suppliers ofthese dual-use items and various ways to importthem. Little of the equipment for final assemblyof a weapon is sufficiently specialized to be easilycontrollable by export laws. Some of the machinetools might be amenable to export monitoring,however, and may therefore serve as preliminaryindicators of a program (see ‘signatures’ sectionbelow).~z A1-Atheer plant Pro8ress Report for the Period 1 January 1990 to 31 May 1990, -X to the SiXth @Wtion RCPOIZ U.N. S-VCouncil S/23122, Oct. 8,1991 (English), p. 14, reprinted as app. B of Peter Zimme~ ‘@’s Nuclear Achievements: Components, Sources,and Stature,’ Congressional Research Service report 93-323F, Feb. 18, 1993. See also p. 20 of main text.73 worltom “some M@ about H.@-PdormIuIw Computers. . .,” op. cit., footnote 69.74 SW, for e~ple, RoIxrt N. Thorn and Donald R. Westervel$ ‘‘Hydronuclear &lXrimentS,” Los Alamos National Laboratory ReportLA-10902-MS, February, 1987.

Chapter 4-Technical Aspects of Nuclear Proliferation I 153Box 4-E – Utility of Tests at Various YieldsThe decision to test a nuclear weapon must weigh the benefits of validating the design against the risks andpolitical implications of the test’s being detected. Tests with substantial nuclear yields can provide importantinformation about a weapon design, but they are likely to be detected. Certain aspects of nuclear bomb designcan be validated even at very low explosive yields. The following TNT-equivalent-ranges illustrate possible usesfor such tests: 1No nuclear yield: With proper diagnostics, scientists can study implosion techniques, compression efficiency,and neutron initiator performance by substituting nonfissile material for HEU or plutonium.Less than 1 kilogram (kg) nuclear yield; So-called “hydronuclear tests” at these yieids were carried out byLos Alamos during the testing moratorium of 1958-1961 to study certain characteristics of nuclear warheaddesigns.1 to a few kilotons (/d): Fission weapons of both gun-type and implosion designs can be tested at full or almostfull yields in this range. in addition, tests involving boosted-fission designs may be carried out within this yield range(see app. 4-A).150 kt: The Threshold Test Ban Treaty of 1974 between the U. S., U. K., and former Soviet Union forbidstesting at greater than 150 kt yields. However, advanced nuclear powers can probably design thermonuclearwarheads with up to multimegaton yields without testing above the 150- kt threshold.Atmospheric tests: Above-ground tests can be used to measure electromagnetic pulse, radiation, blast,fallout, and cratering phenomena that are much harder, or impossible, to study with underground tests.if a proliferant state decides not to carry out nuclear tests with appreciable nuclear yields, it could probablystill design reliabie first- generation gun-type or implosion fission weapons with yields similar to the Hiroshima orNagasaki bombs, With a small number of tests at yields of a few to 10 kt, it may also make progress towarddeveloping more compact or efficient weapons, possibly incorporating boosting. Atmospheric tests are highlyvisible, but they are not required to verify the basic function of nuclear explosives.1 See, for example, Ray E. Kidder, “Militarily Significant Nuciear Explosive Yields,” Federation of AmericanSa”enfists Pub/ic Merest Reporf, vol. 37, No. 7, September 1985; and Dan Fenstermacher, “T%e Effects of NuclearTest-ban Regimes on Third-generation-weapon Innovation,” So”ence & G/oba/ Secudty, vol. 1, Nos. 3-4 (1990), p.193.EXPERIENCE FROM CIVILIAN NUCLEARPROGRAMSThe infrastructure and experience gained fromcivilian nuclear research and nuclear powerprograms would be of substantial benefit to anuclear weapon program. Up to a certain point indeveloping a civilian nuclear fuel cycle, itstechnology is virtually identical to that used forproducing fissile materials for weapons. Relevantexperience would include the ability to handleradioactive materials, familiarity with chemicalprocesses for fuel fabrication and with materialshaving specific chemical or nuclear properties,and the design and operation of reactors andelectronic control systems. Although this kind ofexperience is not unique to the operation ofreactors--and is neither necessary nor sufficientto produce a weapon—it would provide a technologybase upon which a nuclear weapon programcould draw. Furthermore, the infrastructuresupporting nuclear power generation and itsassociated fuel cycle can provide cover forelements of a weapon program, even in acountry subject to IAEA safeguards.RECRUITMENT, FOREIGN TRAINING, ANDINDIGENOUS EDUCATIONThe principles of nuclear weapons can bediscovered without any prior design experienceby any competent group of theoretical and experi-

154 I Technologies Underlying Weapons of Mass Destructionmental physicists and engineers. Although thespecifics of designing, analyzing, testing, andproducing a nuclear explosive device are certainlynot taught in graduate schools, nuclearengineering and physics curricula inevitably providea basic foundation for work in the area ofnuclear weapon design. Indeed, students frommany countries each year go abroad for instructionin such fields at top universities.A country wishing to pursue nuclear weaponscan also adopt its design methodology to theexpertise at hand. Given scientists with onlylimited confidence in their design ability, such astate might choose to develop a very conservativeimplosion design that was not highly dependenton the quality of compression, or a gun-typeweapon using HEU that, while bulkier andrequiring more fissile material, would be mucheasier to build. First-hand design experiencewould be essential only to develop more sophisticatedconcepts, such as advanced or boostedfission weapons, high yield-to-weight weapons,or second-generation (thermonuclear) weapons.Nevertheless, the assistance of outside expertswith specific knowledge of nuclear designcan significantly accelerate a program byavoiding ‘(dead-ends?’ that could waste valuabletime and resources. Countries such as Iran,North Korea, Algeria, and Libya may well requirea very long time if they were to start up aManhattan-Project-like program, without accessto experienced weapon designers. If too muchtime or money is required, then the risks of beingdiscovered by outsiders (or even by internalpolitical opposition) would increase, and a countrymay simply decide to abandon its program ornot pursue it in the first place.At least one case is already known, however, ofone country’s nuclear design information beingused by another country’s nuclear program. YuliKhariton, the physicist who led the effort todevelop the first Soviet nuclear weapon, recentlyadmitted that the Soviets had obtained the designof the frost U.S. plutonium weapon shortly after itwas used on Nagasaki. He claimed that thisenabled the Soviets to carry out their first nucleartest 2 years ahead of schedule-in 1949 instead of1951. He said that it was not until 1951 that theydetonated a device based on their own design. 75There have also been various unconfined reportsof Chinese nuclear design information being usedby Pakistan. 76According to the U.S. State Department, dozensof key Russian scientists would likely be ableto direct critical aspects of a weapon program ina developing country, and perhaps 1 or 2 thousandtechnicians possess highly useful technicalskills. 77 Several dozen nuclear scientists from theformer Soviet Union (though probably not weapondesigners) have reported been working in Iran,with dozens more entering other Middle Easterncountries. 78 Russian and Western specialists,however, say that so far they have no hardevidence that any attempt at recruiting actualnuclear weapon designers has been successful. 79In any case, the expertise needed to produceweapon-usable material and to make it into adeliverable weapon spans a wide range of disciplinesand requires the right mix of individuals.Recruiting any given nuclear weapon specialist75 Serge sc~emq 1‘1 st Soviet A-Bomb Built from U.S. Data, Russian says, “ New York Times, Jan. 14, 1993, p. A12. Kharitonclaimedthat the design was obtained with the help of spy Klaus Fuchs soon after the U.S. bombs were dropped on Hiroshima and Nagasaki in August1945.m see, for ~xmplc, He~ck f;~~ ‘4A Bomb Ticks in pa.kk~” New York Times Magazine, Mar. 6, 1988, P. 38.77 1‘Redfiec~g ~e Soviet w~pm Establishment: ~ ~te~iew wi& Ambassador Rofxrt L. Gallucci$’ Arm control Todu)I, VO1. 22, No.3, June, 1992, pp. 3-6.78 ~temiew with David h-vi, director genend of Israel’s Defense Ministry, in Etha.a Bronner, ‘‘Israel Fears a Flow of IAuil Expertise tothe Middle East,” Boston Globe, June 22, 1992, p. Al.79 pad --Judge, “In Republics, An Eye on Bombs, Scientists,” Boston Globe, June 23, 1992, p. A14.

—.Chapter 4-Technical Aspects of Nuclear Proliferation | 155could have significant or only marginal utility,and would depend strongly on the particularneeds of a country at the time.I costsREQUIRED INFRASTRUCTURETo develop nuclear weapons indigenously, agovernment must make a serious and long-termpolitical commitment, must allocate significantamounts of resources and expertise, and mustconstruct large facilities. (The required steps aresummarized for uranium- and plutonium-basedweapons in figure 4-1 and table 4-l). Since nuclearprograms can vary tremendously, depending on acountry’s choices about paths, organization, secrecy,and goals, absolute costs are difficult toestimate. For instance, the path chosen by acountry would strongly depend on its technicaland industrial infrastructure, Moreover, the costsof developing the special nuclear materials cannotbe directly compared with the costs of commercialenrichment facilities or spent-fuel reprocessingplants for nuclear power reactors, sincefacilities to produce only enough material for oneor a few weapons per year can be tens of timesmore expensive per unit material processed thancommercial facilities, but hundreds of timessmaller. Steps to keep a program clandestine canalso add considerably to the overall cost.The Iraqi program, which appears to have beenaimed at a small arsenal rather than a singleweapon, took multiple paths and pursued its goalsunder tight secrecy. Starting in 1981, after theIsraeli bombing of the Osirak reactor, Iraq apparentlydevoted its effort to producing enricheduranium instead of plutonium and began buildingcomplex research and production facilities (includingtwin sites for EMIS separation). Such aprogram can easily absorb much more money—perhaps as much as 10 to 50 times more—thanthe baseline plutonium-based program describedbelow, and can run upwards of $10 billion. 80 Eventhen, it cannot be assured of success or ofremaining secret. If nothing else, Iraq’s programshowed that there is a vast difference in costbetween the cheapest direct route to nuclearweapons and a clandestine route taken by acountry with little nuclear-weapon relevant experience,but relatively lofty nuclear ambitions. 81WEAPON MATERIALS DOMINATE THE COSTIn general, the acquisition of sufficientquantities of weapon-grade materials presentsnot only the greatest technological hurdle, butalso the greatest financial burden to the wouldbeproliferant. In the unlikely case that thegovernment of a country without prior enrichmentor reprocessing capability were to initiate anuclear weapon program overtly, it could probablybuild a small production reactor and reprocessingplant more cheaply than it could produceequipment to enrich uranium. To remain hidden,however, a plutonium-based weapon programmay have to take difficult and expensive measures.For instance, a proliferant might be driven tobuild a production reactor underground and to tryto disguise its heat emissions to avoid beingdetected by infrared surveillance. If a country hadno reason to reprocess spent fuel for commercialpurposes, the discovery of a reprocessing facilitywould probably indicate weapons intent, so thatsteps might be called for to hide such a facility aswell, or at least to keep it from being inspected. 82go For ~mp~son, tie M~t~Dis~ct project spent $1.9 billion in 1940s dollars (which translates to about $10 billion in 1992 doll~s):50?Z0 to Oak Ridge for uranium enrichment 20% to Hanford for plutonium production and about 4% to weapon-related R&D at Los Alamos.See, for example, Zimmerman, op. cit., footnote 72, p. 4.s I see also ~omas W. Graham, ‘ ‘The Economics of Producing Nuclear Weapons k Nth counties, ’ Strategies for Managing NuclearProliferation: Economic and Political Issues (Lexingtow MA: Lexington Books, 1983), pp. 9-27.82 For fitmce, Nofi Korea>s cl~ hat tie faclli~ at Yongbyon is for peaceful radiochemis~ rese~h (including sepmation Of plu[OIlhlIIl)is particularly questionable, since that coun~’s nuclear power industry is still in its infancy and could not be expected to derive benefits fromplutonium recycling anytime soon.

156 I Technologies Underlying Weapons of Mass DestructionTable 4-8-Nominal Costs for an Overt Small-Scale Plutonium-Based Weapon Program(in millions of 1992$)Capital Costs of Construction:Uranium Mining Site (55,000 t ore/yr): 1.5-15Milling Plant (100 t U 30 8/yr): 8-9Conversion Plant (85 t uranium-metal/yr): 12-14Fuel Fabrication Plant (85 t natural-uranium-fuel/yr): 6-1030-MWt Production Reactor: 35-100(Brookhaven-type, air-cooled, graphite moderated, aluminum-dad naturaluranium fuel; lower cost is for “stripped down” facility with Iittle shielding)PUREX Reprocessing Plant: a 12-36(85 t heavy metal/yr, very low burn-up fuel, batch processing, recovering about10 kg plutonium/yr; low estimate is for rudimentary facility with little radiationshielding)RDT&E costs for the above facilitles: b 10-30(10% - 15% of the capital costs)Start-up costs for the above facilities: 15-45(20°/0 - 25% of the capital costs)Design and manufacture of the first nuclear weapons: 20-65(includes capital costs of the weapon laboratory, RDT&E of the design phase,and nonnuclear components; 20-25% of the total cost of plutonium production (allabove costs))Total cost of first plutonium-based weapon:$120-$300 milliona pUR~ ~ta~ for @Monium-umnium rsdox ext~ction process, a ~dely IJS~ meth~ whereby uranium and plutonium areremoved from spent fuel through a series of chemical processes.b Research, ~velopment, te9ting, and englnedng. This and the “design ad manuf~ture” @sts are b~d on early Btitish andFrench nuclear weapon experience. Figures are adjusted to account for assumed cost reductions in RDT&E that resulted from“international nuclear learning” that took place most rapidly between about 1955 and 1960.SOURCE: Adapted from Stephen M. Meyer, The Dynamics of Nudeer Proliferation (Chicago, IL: Univ. of Chicago Press, 1964), pp.194-203.A minimum-cost plutonium programOne detailed study has estimated that facilitiessufficient to produce about one nuclear-weapon’sworth of plutonium per year could be built for aslittle as $120 to $300 million (in 1992$), if thestate building it did not try to keep it secret (seetable 4-8). 83 This estimate includes the necessaryuranium mining and processing facilities, asmall production reactor to produce the plutonium,and a primitive reprocessing plant torecover it. Since few if any countries are likely toinitiate such a program openly, this number isunrealistically low, but it can serve as a point ofcomparison for more detailed country-specificassessments.According to this study, a country that hasdeposits of uranium ore could setup mining andore processing (called “milling”) facilities thatwould be sufficient to fuel a small productionreactor in roughly 2 years, and without majorexpense or difficulty. Fuel fabrication, in theory,could be done in a common metalworking shop,although typically it has required imported facilities.The production reactor itself could be basedon the Brookhaven Graphite Research Reactor, a1955 design that has long been described in83 St@e~ M. M~e~, TheDy~l~”cs OfNUClearprOliferotiOn (~~go, ~: ufiv. of ~cago FNSS, 1984), pp. lw203. AISO see the ~li~cost-estimate studies done by the United Nations in 1%8 and by the U.S. Energy Research and Development AdmKu “ ‘stration (ERDA) in 1976,as discussed in GrahanL ‘‘The Economics of Producing Nuclear Weapons in Nth Countries, ’ op. cit., footnote 81.

Chapter 4-Technical Aspects of Nuclear Proliferation I 157unclassified U.S. Atomic Energy Commissiondocuments. It is rated at 30 MW thermal outputand if devoted to plutonium production, couldproduce enough for at least one nuclear weapon ayear. (If a state seeking to build such a reactorcould not do so indigenously, it could be forcedto import specialized reactor components such asultra-pure graphite. Such imports from an NPTstate would trigger safeguards.)Data regarding the design, construction, andoperation of reprocessing facilities were alsodeclassified and distributed through the 1955Geneva conference on the peaceful uses of atomicenergy. However, despite using chemical processessimilar to those in standard industrialprocedures, the reprocessing plant could be themost difficult step in this approach, due to theradiological hazard it would pose to plant workers.Nevertheless, radiation risks can be minimized(and the quality of the plutonium forweapon use improved) by irradiating the fuel tolevels that are extremely low compared to thoseattained by commercial reactors—say, a fewhundred megawatt-days per tonne of fuel (MWd/t), as opposed to 10,000 to 33,000. A smallreprocessing facility could probably be built overthe course of 3 to 4 years.The total number of competent, experiencedengineers needed over the course of several yearsto direct the construction of a Brookhaven-typegraphite-moderated reactor and an associatedreprocessing plant has been estimated to be about10 to 20, together with a workforce of severalhundred. 84 Cost estimates for the entire program(adjusted to 1992 dollars), including mining,milling, and fuel-fabrication facilities, are itemizedin table 4-8. Many developing countries witha modest technical infrastructure could constructsuch facilities, and the cost of obtaining thetrained specialists would constitute only a smallfraction of the total weapon-program costs.Reports in the open literature indicate that twocountries have pursued unsafeguarded productionreactors of approximately the size assumed here,although their cost data are not known. NorthKorea recently declared that one of its twooperating reactors at Yongbyon is rated at 5MW(e), but many Western analysts believe it is a30 to 50 MW(t) production reactor. 85 Unofficialreports have alleged that Pakistan may havebegun building a similarly rated (50 MW(t))reactor in the mid-to-late 1980s. 86A more ambitious program aimed at indigenousconstruction of a 400-MW(t) productionreactor and 10 to 20 weapons per year wouldrequire either a fairly high level of industrializationor a considerable nuclear technology baseupon which to build. The only known unsafeguardedreactors with roughly this output (outsidethe five declared nuclear weapon states) arethe five 220-MW(e) heavy -water reactors (HWRs)operating in India, and possibly Israel’s DimonaHWR, believed by most to have operated at 40 to70 MW(t), 87 but by some at up to 150 MW(t). 88India has five other indigenous HWRs underconstruction, and North Korea has recently declaredthat is it constructing two power reactorswith approximately this power rating-a graphitepower reactor at Yongbyon rated at 50 MW(e) (inaddition to two smaller reactors already in operationthere), which would give it a thermal outputof 150 to 200 MW(t), and a larger reactor atTaechon projected to have a power rating of 200u Meyer, ibid.as See testimony of R. James Woolsey, Feb. 24, 1993, op. cit., footnote 15; and Spector, Nuclear Ambitions, OP. cit., foomote 16 PP. 128+139.86 See Sp=tor, Nuclear Ambifions, op. cit., footnote 16, p. 116.07 fiid., pp. 83-4, 172.88 “Revealed: The Secrets of Israel’s Nuclear Arsenal, Sunday Times (London), Oct. 5, 1986, p. Al.

158 I Technologies Underlying Weapons of Mass DestructionMW(e) (roughly 600 MW(t)) once completed. 89By one estimate, a reactor of several hundredMW(t) would normally take 5 to 7 years tocomplete, would require an overall capital investmentin the range $4OO to $1,000 million (1992$),and would require about 50 to 75 engineerssupported by roughly 150 to 200 technicians forits design and construction. 90 Others estimate thatpractical difficulties normally encountered inconstructing such facilities could increase thesefigures by up to 100 percent. 91Costs for small-scale uranium enrichmentCosts for a dedicated (and possibly clandestine)enrichment facility are extremely difficult toestimate, both because the procurement route andchoice of technology are much more uncertainthan for an indigenously built reactor and reprocessingplant, and because experience and openlypublished data relevant to enrichment facilitiestend to be associated with very large commercialplants built for the nuclear power industry. (Thecost can be much cheaper per unit enrichmentcapacity for large plants,) Nevertheless, a nominalidea of costs can be derived from smallercommercial facilities. Excluding research anddevelopment, the total cost for constructing acentrifuge facility capable of producing 300 kgHEU per year-12 times the IAEA significantquantity-might run from $100 to $500 million(in 1992$). 92 A smaller facility to produce about15 kg of HEU per year based on calutron (EMIS)technology has been estimated to cost a minimumof $200 million. 93 If a sma11 amount of additionalenrichment capacity-say, enough for 30, ratherthan 300, kg of HEU per year-were to be builtby a country already knowledgeable about themanufacture and operation of centrifuges, thecosts could conceivably be much lower, perhapsonly $2 to $5 million. The costs of building andoperating such a facility in secret at a clandestinelocation, however, might increase this figuresubstantially.| Implications of New Materials-ProductionTechnologiesURANIUM ENRICHMENT TECHNOLOGIESAlthough France, Japan, and the United Stateshave made substantial progress in the last 10 yearsdeveloping laser enrichment processes, successfullyintegrating laser or other advanced technologiesinto a facility capable of producing kilogramquantitiesof HEU will probably remain beyondthe reach of the developing countries for sometime. Even in the most technologically advancedcountries, these methods have tended to require alengthy development period, and the quantities ofmaterial produced in the early stages has beenvery small. In contrast, technologies such asaerodynamic methods and centrifuges may offerpotential proliferants a more attractive mix ofcharacteristics. As evidenced by South Africa andPakistan, these techniques appear capable ofbeing developed successfully by countries havingeither a substantial technology base or access tosensitive design data.89 ~oe Jong SW spoke- for North Korean Mnistry of Atomic Energy Industry, in interview with Leonard S. Spector, May 3, 1992,Pyongyang, as posted on Nuclear Nonproliferation Network.90 Meyer, The Dy~~”cs Of Nuclear proliferation, Op. cit., foo~ote 83.91 G~rge A.IEAou ~Sociate division leader of Z-Division, Lawrence Livermore National Labomtory, private communication Aug. 16,1993.92 U.S. CoWess, OffIce of Technology Assessment, Nuclear Prol~eration and Safeguards, op. cit., footnote 24, P. 1*O.93 @w~d F. Schuette, 4 ‘Electromagnetic Sep~tion of Isotopes, ‘‘ in OTA, Nuclear Proliferation and Safeguards, op. cit., footnote 24, vol.II, Part 2-VI, p. 105; costs have ken converted to 1992 dollars.

Chapter 4-Technical Aspects of Nuclear Proliferation | 159TECHNOLOGIES AFFECTING PLUTONIUM FUELCYCLESPlutonium isotopic purificationThe longer that reactor fuel containing uranium-238 is irradiated in a reactor, the higher will be itsproportion of undesirable isotopes in the plutoniumthat is created, making it less desirable fornuclear weapons than pure plutonium-239. (Seeapp. 4-A and the discussion earlier in this chapteron the use of reactor-grade plutonium in nuclearweapon s.) Just as uranium-235 can be separatedfrom uranium-238 to obtain bomb-grade material,so can plutonium-239 be separated from theseother plutonium isotopes. Laser isotope separation(LIS) techniques, for instance, although notoriginally developed for that purpose, might beused. 94 Plutonium-239, in theory, could also be‘‘enriched’ using centrifuges, EMIS, or evengaseous diffusion methods, though developingconversion facilities to produce the requisiteplutonium compounds would be a major undertakingrife with its own set of problems.Liquid-metal fast breeder reactors (LMFBRs)Development of LMFBRs (reactors that arecapable of breeding plutonium at a faster rate thanthey consume it) has progressed much less rapidlythan was predicted in the 1970s. The principalbreeder reactor programs have been located inJapan, France, and the former Soviet Union(mainly in Kazakhstan) .95 But France suspendedoperation of its 1,200-MW(e) production-scaleFBR, called Superphenix, in 1990, and Germanyand the U.K appear to be abandoning their effortsto develop breeders.LMFBRs introduce safeguard concerns farbeyond those faced with the light-water reactors(LWRs) most commonly used for powergeneration. Whereas reprocessing can be forgonefor LWRs, it is integral to a breeder’s fuelcycle. Fresh LMFBR fuel contains a considerablylarger fraction of plutonium than does even theplutonium-containing MOX fuel intended for usein commercial LWRs. (LMFBRs such as Superphenixcontain about 5 tonnes of plutonium intheir cores.) Moreover, a considerable amount ofthe plutonium produced in an LMFBR undernormal operation will be weapon-grade, whereascommercial light-water reactors produce muchlower quality (reactor-grade) plutonium unlessshut down and refueled much more frequentlythan economical operation would warrant.Integral Fast Reactor (IFR) fuel cycleIn the future, new plutonium fuel cycles couldalso be developed and commercialized. One suchconcept, which has been under development byArgonne National Laboratory in the United Statesfor many years, is called the Integral Fast Reactor(IFR), 96 The IFR was originally developed toreduce the amount of nuclear waste generated byreactors by “burning” more of the longest livedradioactive byproducts than can be consumed byconventional nuclear reactors. The reprocessingapproach used in an IFR fuel cycle would produceplutonium-containing fuel that is considerablymore radioactive than that resulting from thetraditional PUREX process, thus being less attractivefor diversion to a weapon program. Tohandle it efficiently, reprocessing would occur at94 ~ tie 19go~, th~u.s. D~~~ent of Energy’s plans for alaser isotope sepmation facility to be built in I&#10 included sepWatingplUtOIliUmisotopes. Although economically unattractive compared with more direct methods of obtaining nuclear weapon materials, the possibility ofusing LIS to enrich plutonium has added somewhat to the concern over the Japanese and South African development of pilot I-IS plants.Although both countries already operate reprocessing facilities and have legitimate needs for enriched uranium for nuclear power, thepurification of separated plutonium would provide an additional path for producing weapon-grade plutonium.95 Ka~tan’s SSS.MW(’) fmt bre~er @N.350) dates from Soviet effo~ over tie past 10 to 20 yws and is designed to use 20 to 25%enriched uranium as well as MOX fuel. Potter et al., op. cit., footnote 35, p. 9.96 ~les E, Till and Yoon I. Chang, ‘‘The Integral Fast Reactor,’ Advances in Nuclear Science and Technology, vol. 20 (1988), pp.127-154.

160 I Technologies Underlying Weapons of Mass Destructionthe reactor site itself, in hot cells as close as 100feet to the reactor. 97The proliferation concerns with the IFR fuelcycle, as with other fuel cycles involving reprocessing,center on the accountability requirementsto assure nondiversion of nuclear material at anystage. Since the hot-cell area is small and hasrelatively few access points compared to thePUREX process, it would be more difficult forsubnational groups to divert material from anIFR. However, because the IFR concept wouldrequire a closed-cycle inert-gas environment involvinghighly radioactive materials at hightemperatures, effective materials-accountancy maybe difficult to implement. Instead, safeguards willhave to rely much more heavily on containmentand surveillance measures (see app. 4-Con IAEAsafeguards and the civilian nuclear fuel cycle).Although the prospect of IFRs substituting forconventional LWRs in the United States or evenfor liquid-metal breeder reactors in France orJapan does not appear to be likely for severaldecades, the long-term proliferation and safeguardsimplications of sharing IFR reactor technologywith other countries is yet to be fullyaddressed .98| Weaponization-Going Beyond the“Physics Package”MINIATURIZATIONA nuclear device deliverable by aircraft ormissiles at long range must meet certain size andweight constraints. The bombs used in World WarII, called “Little Boy” and “Fat Man,” eachweighed in excess of 4,000 kg, which would havemade them virtually impossible to deliver by anyballistic missile deployed in the Third Worldtoday, and problematic for over half these countries’combat aircraft, including the F-16, MirageF-1, MiG-23, -27, and -29. (Chapter 5 discussesdelivery systems suitable for nuclear weapons aswell as chemical or biological weapons, andprovides more detail on the capabilities of aircraftand missiles available to states of proliferationconcern.)A nuclear proliferant today could probablyconstruct a much lighter bomb than the first U.S.bombs. Many experts believe that even the500-kg payload limit originally set by the MissileTechnology Control Regime (and since eliminatedat the beginning of 1993) may no longer beappropriate for first-generation nuclear weapons.U.S. 8-inch and 155-mm nuclear artillery shellsproduced in the late 50s and early 60s suggest thatcompact and relatively lightweight warheads canindeed be designed. Although the design of thesewarheads drew on the experience gained fromhundreds of nuclear tests, they may still haverelevance to current proliferation concerns forseveral reasons. First, explosives technology andlight-weight electronics have advanced dramaticallysince the 1950s. Second, other forms oftesting, such as “hydronuclear tests” with extremelylow nuclear yields (see discussion below)may allow at least the more technologicallyadvanced proliferant countries to reduce amountsof materials in their weapon designs to levels wellbelow those of the first U.S. weapons. Third, atleast some knowledge of more advanced weapondesigns (even if from three decades ago) maybedifficult to keep out of the hands of proliferants.Finally, even straightforward modifications to thedesigns of the first U.S. weapons could reducetheir size considerably, albeit with some yieldpenalty, with no greater required sophistication.The mere fact that the United States has builtlow-weight nuclear weapons indicates that theycan be built, considerably increasing a proliferant’smotivation to attempt to recreate such a97 me IFR CaII use mom radiowtive nuclear fuel because it is less sensitive than many Other types of nuclear reaetor to fuel impurities Wabsorb neutrons.98 See, for example, R.G. Wymer et al., ‘‘An Assessment of the Proliferation Potential and International Implications of the Integrtd FastReactor,” prepared by Martin Marietta Energy Systems, Inc. for the U.S. Dept. of Energy and the U.S. Dept. of State, May 1992.

—Chapter 4-TechnicaI Aspects of Nuclear Proliferation I 161design. Their existence also offers the possibilitythat such designs might be stolen, particularly ifthe Soviet Union and other nuclear weapon stateshave developed low-weight warheads as well.ANTI-AGINGUnless assembled immediately prior to use,warheads would have to be storable over someperiod of time to be militarily useful. To makewarheads that were reliable after years of storage,many features might need refinement, includingnondegrading high explosives, purer grades ofplutonium 99 or, with weapon designs that usetritium gas for additional yield, a replaceabletritium supply. Anticorrosive materials might berequired at various points within the weapon, inaddition to metallurgically stabilized nuclearmaterial. Some of these refinements might requiresubstantially more research than what would beneeded for a crude frost-generation weapon.Frequently recycling the nuclear material, reassemblingthe weapon, and inspecting the nonnuclearcomponents could ameliorate these problems,but such measures introduce considerablelogistical problems of their own.REENTRY VEHICLES AND FUZINGAs mentioned above, missile delivery wouldplace constraints on a warhead’s size and weight.For Scud-type missiles, which do not employ aseparating reentry vehicle, these constraints arenot severe. However, if a narrow cone-shapedreentry vehicle were deemed necessary to achievedesirable aerodynamic properties, it would haveto be internally balanced to avoid wobbling ortumbling. l00 Such reentry vehicles would constrainthe configuration of a warhead’s highexplosives and detonators, possibly requiringa more sophisticated design that a proliferantmight wish to test in order to have highconfidence in its performance. l0l It might alsobe desirable to incorporate radar altitude-fuzing,to avoid the added difficulty of designing weaponsto detonate on impact, or salvage fuzing(detonation upon being attacked by an interceptor)to defeat missile defenses. These featureswould likely require flight testing of the reentryvehicle under realistic conditions before fieldingit and would thus increase a program’s visibilityas well as its technical hurdles.SIGNATURES OF NUCLEARPROLIFERATION ACTIVITIESThe IAEA safeguards system provides a meansof monitoring and inspecting peaceful nuclearactivities in a great number of countries. Inaddition, however, individual countries may wishto monitor the potential for other countries todevelop nuclear weapons—both to evaluate anddeal with the security threat that such programscould pose and to assess the effectiveness of andpossible improvements to nonproliferation policies.Every stage of nuclear weapon development,from material production to deployment, cangenerate signatures that provide some indicationof a weapon program’s existence or status,although only a few of them point fairly unambiguouslyto a nuclear weapon program.This section surveys potential signatures of anuclear weapon program without attempting tofully assess the capability to monitor nuclearproliferation or verify compliance with the NPT;such would require evaluating the capability toobserve these signatures, identify them, and piece99 ~utotim.~l, ~Wwatti plutonium isotope, decays into americium-241, which is much more radioactive than plutonium. AS it buildsup within a weapon, that weapon becomes more diflicult to work with and its characteristics can change. Higher grades of plutonium have lessplutonium-241, thus reducing these problems.100 Mthou@ &e pficip~ r-on tit the Wknowledged nuclear powers have attempted to prevent their missile wmhmds from wb~g orwobbling during reentry is to attain higher accuracy, a tumbling warhead’s violent motions and potential lack of adequate heat shielding couldalso affect reliability.lo] Testing Wodd alSO be much mom important if a proliferamt were seeking to develop very low-weight warheads to accommo~te limitedpayload capacities of certain types of ballistic or cruise missile.

162 I Technologies Underlying Weapons of Mass Destructionthem together with other sources of informationto arrive at timely conclusions regarding particularstates’ activities.| Materials AcquisitionURANIUM OR PLUTONIUM DIVERSION FROMSAFEGUARDED FACILITIESUnder the mandate of the NPT, IAEA safeguardsfocus narrowly on a specific goal-timelydetection of diversion of significant? quantitiesof fissile nuclear materials from facilities declaredto be peaceful in purpose (see app. 4-C onsafeguards). The detection of such diversion,or the discovery of unsafeguarded nuclearfacilities in a state that had committed to placeall its facilities under safeguards, would generatestrong suspicions of a nuclear weaponprogram.Safeguards primarily operate indirectly, byverifying that all nuclear materials are accountedfor. (They are supplemented at certain types offacility by containment and surveillance techniques,which in principle could detect sometypes of diversion directly. 102 ) Material accountancyseeks to verify the correctness of a plant’sown operating records, much as an audit of afinancial institution verifies its bookkeeping.Over the past 15 years, material accountancytechniques have improved significantly. Safeguardsalso make extensive use of automatedequipment for measuring controlled items and forsupporting containment and surveillance techniques.In addition to evidence of diversion acquiredthrough material accountancy or containment andsurveillance, certain behaviors might also raisedoubts about a safeguarded country’s intent tocomply with its nonproliferation agreements.Behaviors detectable through normal safeguardsinspections could include: stalling tactics (e.g.,unsubstantiated complaints about individual inspectorsor repeated exclusion of inspectors withcertain nationalities) 103 ; barring inspectors’ accessto certain areas or facilities for suspiciousreasons; having substantial or repeated materialunaccounted-for(MUF) l04 ; or keeping inconsistentrecords. If detected by other means, constructionof undeclared ‘pilot facilities that appearedto be destined to contain nuclear material wouldalso raise suspicions, as would refusal of an IAEArequest for a special inspection at such a facility.l05URANIUM ENRICHMENTIf operated on a large enough scale (perhaps 10bombs-worth per year), an energy-inefficientenrichment technology such as EMIS or gaseousdiffusion might be detectable by its heat emission.At Iraq’s A1-Tarmiya facility, for instance, heatrejection into the air or, as appears to have beenplanned, into the Tigris river, might well havebeen observable once operation had begun. 106However, at lesser production rates or with more102 Conbmt ~d ~ei~(:e ~iprnent includes unattended video cameras, motion detectors, closed-ciscuit ~ Systems, ~d vfioustypes of seals.103 Undm IAEA s~e~ds, a CCWIh-y has the right to reject inspectors of whatever rWiOMlities it chooses (Or, for that mtitter, fOr my Otherreason), a right that is regularly exercised. For example, between 1976 and 1981 (the year that Israel attacked the Imq’s Osirak reactor), Iraqallowed only Soviet and Hungarian nationals to perform safeguards inspections on its territory. ‘lMimony of Roger Richter, fomer IAEA@tor in ~~! cit~ in J. Aso~tY) K-A. WOlf, E.C. Rivm, Do~sfic Implementation of a Chemical Weapons Treaty, Rand ReportR-3745-ACQ (Santa Monica, CA: MND Corp., C)ct, 1989), p, 55,10.i ~~~te~.mcomted-for’ is a s~egu~ds term describing differences betweenmeasured ~d expected values fi~tti~ ~~un~cy.MUF can result from normal measurement or calibration errors, or can indicate a possible diversion of materials.los See, for ~~ple, George B~ Does the NPTRequire its Non-Nuclear Weapon Pam”es to Pew”t Inspection by the IAEA of NuclearActivities That Have Not Been Reported to the IAEA? (Stanford, CA: Center for International Security and Arms Control, Stanford University,Apti 1992).106 ~~ony F~~rg, S~engthening I- Safeguard.r: Lessonsfrom Iraq (Stanford, CA: Center fOr kte~tioti s~urity Arms control,Stanford University, April 1993), p. 21.

.Chapter 4-Technical Aspects of Nuclear Proliferation 1163efficient technologies (e.g., centrifuges, or EMIStechniques that employed permanent magnets andlower beam-voltages), heat signatures would beless evident. Heat emission is a nonspecificsignature, however, that would be most useful formonitoring the startup and shutdown patterns ofknown facilities; it would have to be combinedwith other indicators to determine whether agiven unknown facility were nuclear-related.A potential sign of a clandestine enrichment orother nuclear facility could be unexplained specialsecurity or military reinforcements around anindustrial site. These arrangements might bevisible from overhead or from the ground.At close enough range, other signatures wouldbecome observable. For example, even a verysmall centrifuge plant might emit detectableacoustic or radiofrequency noise, and the pulsedlasers used for laser isotope separation emitcharacteristic electromagnetic signals at kilohertzfrequencies that might be detected, Samples ofsubstances taken from either declared or suspectfacilities could also indicate their potential forproducing weapon materials. For example, UCL 4or other uranium chloride combinations couldindicate EMIS or Chemex enrichment technology,and UF 6, UF 4, HF, or uranium metal couldindicate other uranium enrichment techniques(see app. 4-B). 107 Analysis of environmentalsamples containing depleted or enriched uraniumin water or soil would also provide very importantsignatures.Patterns of foreign procurement of essentialmaterials and parts, such as newer highstrengthmaterials or maraging steel (a veryhigh-tensile-strength steel used to manufacturesome types of gas centrifuge), or large ironelectromagnets, high-voltage power supplies,and large vacuum systems (for EMIS), mightalso help to indicate a county’s intentions.PLUTONIUM PRODUCTIONAn indigenous uranium mining industry mightprovide early indication of a clandestine uraniumor plutonium-based weapon program and is a sureindicator of at least the possibility. For theplutonium path, natural uranium could fuel agraphite- or heavy-water moderated plutoniumproductionreactor. A sizable research programinvolving breeder-reactors or the production ofheavy water or ultra-pure carbon and graphiteproducts might also be cause for concern, especiallyif such programs were not easily justifiableon other accounts.Small research or power reactors with highneutron flux and significant amounts of uranium-238 in their cores can also be used to produceplutonium. However, a 40 to 50 MW(t) undeclaredreactor (enough to produce plutonium forat least one bomb per year) should be easilydiscernible to overhead infrared sensors, at leastif it is built above ground and located away fromheavy industrial areas (such a location might bechosen for security and safety reasons anyway).108 Insections of safeguarded reactors,especially if carried out at more random intervals,might detect unnecessary placement of uranium-238 in or around the core, augmenting the rate ofplutonium production. Similarly, inspections ofCANDU-style reactors (a heavy-water-moderatedreactor that can be refueled online) or offrequently shut-down LWRs should call attentionto very low-bum-up fuel cycles, from which theplutonium produced is predominantly plutonium-239, the isotope best suited for weapons.lo7 Note, however, that the specific compounds UClq and UF6 would not likely be found in the atmosphere, Skim they Hct very qticMY ~~water to form other compounds. The existence of IJFA might also be evidenced by the particular processing equipment required to reduce itto metallic form.Im ]f the heat were dischmged into a modest-simd river, a resulting rise in temperature on the order of O. 1“C or more (depending on flow-rate,mixing, etc.) would be detectable in the far-infrared. Alternatively, heat from the cooling towers might also be detectable. See Fainberg,~trengrhening IAEA Safeguards, op. cit., footnote 106, p. 21..

164 I Technologies Underlying Weapons of Mass DestructionSPENT-FUEL REPROCESSINGIn general, the plutonium-production route,which involves reprocessing of spent reactor-fuelto extract plutonium, would be easier to detectthan would be a small-scale clandestine uraniumenrichmentfacility. l09 Plutonium and uraniumfrom spent fuel (as well as enriched uranium fromresearch reactor cores), is reclaimed by choppingup and dissolving the fuel elements in acid,subjecting the solution to solvent-extraction andion-exchange processes, and chemically convertingthe plutonium and uranium in the resultingliquids to metallic or oxide forms. Methods fordoing this, including the most common one,known as PUREX, involve various wellunderstoodchemical processes that use characteristicgroups of materials.Detection of these materials, either by environmentalsampling or by impactions, could indicatereprocessing activity. 11O Some chemicals mightalso be observed through export monitoring; forexample, high-purity calcium and magnesium,which are used in the metal-conversion step, areincluded in the Nuclear Supplier Group’s new listof sensitive dual-use items to be subjected toexport controls (see app. 4-D).Release of noble gasesIn addition to the characteristic chemicals usedin the PUREX process, effluents from reprocessingplants will contain telltale radioactive fissionproducts, including radioactive isotopes of thenoble gases xenon and krypton-especially krypton-85—and possibly argon. lll Measurements madeat the U.S. reprocessing facility at the SavannahRiver Plant in South Carolina have suggested thatkrypton-85 may be detectable, even from smallfacilities, at ranges of 10 kilometers or more. 112Isotopic content of plutoniumAnalysis of plutonium samples or effluentsfrom reprocessing could provide further evidenceof weapon intent by revealing the fuel’s irradiationlevel. For most types of reactor, a very lowfuel-irradiation level would be a strong indicatorof weapon activity. In addition, isotopic correlationtechniques-which compare the isotopicratios of different samples of plutonium-canprovide sensitive indicators of plutonium productionhistory or material diverted from one facilityto another. 113| Weapon Design and IntentACTIVITIES OF SCIENTISTSThe effort required to develop nuclear weaponscan have a significant effect on the movement,publications, and quests for information of acountry’s leading scientists. Although publicationson nuclear materials and reactors would beexpected in connection with legitimate safeguardedactivities, a sudden decline in thesepublications might be suspicious. Scientists directedto pursue a weapon program might beginseeking out specialized computer codes (especiallyadapted to high pressure and high temperatureregimes) or attending a greater number oftechnical conferences in the areas of opticalinstrumentation, reactor-core neutronics, or highexplosivesand shock-wave hydrodynamics. They109 Any -~eWdedex@f:n~tionwi~repr~ess ~by~~nonnuclem-weapon s~tewotid be suspicio~, andreprocessing activityhas traditionally been a cause for c:oncem in any nomuclear-weapon states, whether party to the NPT or not.110 ~om aci~, O%aniC and inorgdc solvents, and other chemicals are used in the PUREX process, as well M uranium and plutoniumthat would be present at each step. !;ee, for example, Richard R. Paternoster, ‘‘Nuclear Weapon Proliferation Indicators and Observable,’ LosAlarnos National Laboratory, LA-12430-MS/UC-700 (December 1992).111 Fr~vonHip@ and BarbaraUvi, ‘‘ Controlling Nuclear Weapons at the Source: Verif3cationof a Cutoff in the Production of Plutoniumand Highly EMched Uranium for Nuclear Weapons, ” Kosta Tsipis et al., Arms Control Verification: The Technologies That Make it Possible(Washington DC: Pergarnon-Brassey ’s, 1986), pp. 351-53.] 12 mid.113 ~ex DeVo]pi, Argonne Nal!ional Laboratory, private communicatio~ Dec. 14, 1992.

Chapter 4-Technical Aspects of Nuclear Proliferation | 165might also begin purchasing large numbers of NUCLEAR AND HIGH-EXPLOSIVE TESTlNG1 17declassified documents from foreign weaponlaboratories. (Such documents were indeed found Implosion physicsamong those seized in Iraq.) A sudden recall of Repeated high explosive (HE) tests are generallyrequired before a workable implosion-typetrained scientists from other countries would beanother observable, as would attempts to recruit nuclear weapon can be designed. 118 Explosiveforeign weapon scientists. 114 Sending large numbersof graduate students abroad to study techni-propel metal objects would usually require elec-tests to study either the HE alone or its ability tocal fields related to nuclear weapon design might tronic or optical instrumentation. For observers atbe associated with a weapon program. However, close enough range, some indicators of highexplosivetesting activity are the following: 119such a signature would be very ambiguous, sinceat the graduate level, most such fields haveexpansion of facilities or personnel at or nearwidespread application.an existing ordnance plant;purchase or production of explosives moreDECLARATIONS OF LEADERSenergetic than pure TNT, such as RDX,Public statements by high officials can also HMX, or PETN, any of which could beshed light on a nation’s intentions, though they mixed with TNT;must be interpreted within a given political equipment for compacting or melting andcontext. For instance, statements from Iraq before casting HE, perhaps modified from whatthe 1991 Persian Gulf War and from Iran after that would be used at a standard ammunitionwar could be interpreted to indicate a desire for loading plant;weapons of mass destruction:alternatively, for different types of explosives,isostatic or hydrostatic presses, weigh-. . . it behooves us to declare clearly that if Israelattacks and strikes, we will strike powerfully. If it ing many tons and likely remotely controlleduses weapons of mass destruction against our (some antitank shaped-charges are also madenation, we will use against it the weapons of mass using such presses);destruction in our possession. 115precision, possibly template or computernumericallycontrolled, two-axis machiningSince Israel continues to posses nuclear weapons,we, the Muslims, must cooperate to produce an facilities for HE, especially if suited foratom bomb, regardless of U.N. attempts to machining curved contours and surroundedprevent proliferation. 116 by blast-protection shielding;i 14 RepOm ~ me press ~ve c~ed tit w r~enfly ap~~ed to emigre nuclear engineers to return home, ostensibly to work on civil~applications of nuclear power.115 speechby saddam Hussein at the opening of the Arabs ummit conference in Baghdad, May 28, 1990, translated in FBIS-NEA, May 29,1990, p. 5.116 ha Vice President Ataollah Mohajerani, Oct. 25, 1991, at an Islamic conference in Tehru quoted in George J. Church, “Who Elsewill Have the Bomb?” Time, Dec. 16, 1991, p. 47.117 ~s md the following section draw heavily on material found in paternoster, “Nuclear Weapon Proliferation Indicators andObservable,’ op. cit., footnote 110.118 III order to improve tie s~e~ and effectiven~s of the implosio~ multiple experiments would be called for, iIICIUd@ mefiue’mentof the resulting core density.119 Paternoster, “Nuclear Weapon Proliferation Indicators and Obsemables,” op. cit., footnote 110, pp. 7-9.

166 I Technologies Underlying Weapons of Mass Destruction■ waste and scrap from the above operations,possibly including effluent waste-water systemsinvolving filters or catch basins; pronouncedred coloration in waste water causedby dissolved TNT; solid scrap periodicallydestroyed by burning or detonation; and■ instrumented firing stations and control bunkersfor HE or HE-metal tests using chargesweighing up to hundreds of pounds. 120Test-firing of HE-metal systems containinguranium would be indicated by the following:bright streamers radiating from the test(caused by burning fragments of uranium)visible to the eye;local debris or dust that contained uranium;andnearby fire-extinguishi.ng equipment, portableradiation monitoring equipment, or permanentair-sampling radiation-monitors.Since highly dense (but nonfissile) uranium-238 is widely used in certain types of antitankweapon, these indicators could also stem fromadvanced nonnuclear munition programs. Therefore,most or all of these could be associated withconventional munitions production and do notgive unambiguous evidence of nuclear weapondevelopment. However, spherically symmetricimplosions would be more likely connected witha nuclear program.Gun-type weapon developmentGun-type weapons generally require highlyenriched uranium surrounded by neutronreflectingmaterial such as natural uranium, tungstenalloy, or beryllium metal or oxide (ceramic).A development program might use hundreds ofpounds of beryllium or thousands of pounds ofuranium or tungsten for the neutron reflectoralone. Unusually high importation of some ofthese items by certain countries might suggestweapon-development activity. In addition,ground cover at the detonation test-site maybe cleared in only one direction, since thedebris from tests-and especially burninguranium streamers if natural uranium wereused as a mockup for HEU-would beconcentrated in a cone coaxial with thedirection of projectile firing (however, a testprogram for nonfissioning shaped charges orkinetic-energy rounds could also have sucha configuration);special fast-acting very-high-pressure gaugesmight be used to record the pressures in thegun breech; anddistinct acoustic features might be observable.NUCLEAR LABORATORY EXPERIMENTSObservers who had access to suspicious laboratoriesmight detect the following signatures:Criticality tests—weapon designers usingnear-critical fissile assemblies may wish tomeasure criticality with closed-circuit televisionand neutron counters in remotely operated(possibly underground) experiments.However, experiments can also be performedat the bench-top level, not needingelaborate equipment, and much of the relevantdata is already available in the open literature.Moreover, similar facilities are also used foragricultural and biological neutron-irradiationresearch. Any kind of criticality accident at asuspect site, however, would be a strongindicator of weapon-design activity, sinceother applications would be ununlikely towork with near-critical assemblies.Neutron background measurements—forgun-type devices, neutron-flux measurementswould be required to assure that backgroundneutron counts were sufficiently low. Suchmeasurements might be indicated by a roomcontaining neutron detectors that was shieldedfrom external sources of neutrons, for examlm~-n~tjon could involve a few domn high-speed OSCfiOSCOpfX, ti@-@ ~~~ mirror ‘streak’ cameras; electronic-irnafyxonvexteror high-speed framin g cameras; and pulsed x-ray generators.

Chapter 4-Technical Aspects of Nuclear Proliferation I 167ple with water- or polyethylene-filled walls.Such facilities might also be used to testneutron initiators.Development of neutron initiators-neutroninitiators produce a pulse of neutrons toinitiate the nuclear chain reaction at theoptimum moment (see app. 4-A). They useeither alpha-particle-emitting radioactive substancesor small particle accelerators containingradioactive tritium gas, 121 Therefore,import or production of alpha-emitting materials,tritium, or the special facilities tohandle them (similar to those used forspent-fuel reprocessing) could indicate weapondevelopment. However, small acceleratorbasedneutron sources are produced commerciallyfor oil-well logging and laboratoryuse, so that they do not necessarily indicatea weapon program.Special tests—Since neutron initiation is soimportant to the proper detonation of anuclear device, tests involving actual HEwith very small (sub-critical) amounts ofnuclear material would likely be carried outas well. These might be conducted in shallowunderground chambers designed for neutronshielding. (A series of such tests, called‘ ‘hydronuclear experiments,’ was conductedby the United States during the testingmoratorium of 1958 -61.) Some of the surfaceequipment associated with these tests mightalso be telling. 122WEAPON FABRICATIONFinal assembly of nuclear weapons can takeplace at small facilities. Indicators of such facilitiescould include special security arrangementsand structures designed to handle accidentaldetonation of high explosives. These signs, however,could also indicate conventional militaryfacilities.Import patterns of dual-use items might againprovide indicators of intent to fabricate weapons.During their inspections of weapon facilities inIraq, the IAEA found items such as computernumericallycontrolled (CNC) machinery, twoaxislathes, vacuum furnaces, and isostatic pressesthat had been imported through a vast network offoreign suppliers and front companies (see box4-F). Since this equipment has a variety ofindustrial and nonnuclear military uses, it wouldbe very difficult to determine its exact connectionto a nuclear program simply by knowing thequantities being imported. Nevertheless, if sufficientmonitoring could be implemented to detectand analyze changes or unusual patterns ofimport, or if reliable accounts of these items’ultimate end-use could be kept, tracking somesubset of duaI-use equipment might provide anindication of weapon development. The import ofa suite of multiuse items would provide moreimportant information than that of individualitems.Effluents and solid waste from a suspectedweapon-fabrication site might include characteristicsubstances associated with working plutoniummetal ‘‘buttons’ into raw shapes beforemachining, such as tantalum, magnesium oxide,aluminum, graphite, calcium fluoride, plutonium,and plutonium oxide. 123NUCLEAR TESTINGVisible signs of nuclear testsThe Integrated Operational Nuclear DetectionSystem (IONDS) aboard the Global PositioningSystem (GPS) satellites is designed to detect the121 Tritiu, a radioactive isoto~ of hydrogen produced mainly in nuclear reactors dedicated to tbat purpose, is a key element in adv~wd(boosted or thermonuclear) weapons as well as in accelerator-based neutron initiators. It is not subject to safeguards, however.In See RoIxfi N. ‘rhom and Donald R. Westervelt, op. cit., footnote 74; and patemOSter, ‘‘Nuclear Weapon Proliferation Indicators andObservable,” op. cit., footnote 110, pp. 16.123 John E. Dougherty, ‘‘A Summary of Indicators of Nth Country Weapon Development Programs, ’ Ims Alamos Scientific Laboratory,Rq)ort LA-6904-MS, January 1978, p. 4.

168 I Technologies Underlying Weapons of Mass DestructionBox 4-F-lraq’s Attempts to Conceal or Suppress SignaturesA J& .4 “+IAEA inspector David Kay talks with Iraqi militaryauthorities after they deny access to sites at Falluja inJune 1991 in defiance of UN. Security CouncilResolution 687.Iraq successfully concealed both the sizeand level of progress of its nuclear program. 1Four months after the June 1981 bombing byIsrael of Iraq’s Osirak reactor, Jaffar DhiaJaffar (deputy minister of industry, head ofreactor physics at Tuwaitha and now be-Iieved to have been the head of Iraq’s nuclearweapon program) reportedly convinced SaddamHussein that remaining in the NPT whileembarking on a clandestine nuclear weaponprogram would present no serious difficulties.2 Over the next decade, a nuclear programcode-named Petrochemical-3 employedover 20,000 employees-7,000 of them scientistsand engineers--at an estimated costof $7 to $10 billion. This program included atleast two major enrichment programs (EMISand centrifuges, plus preliminary work withchemical enrichment), direct foreign technicalassistance, and massive foreign procurementmuchbut not all of which fell within the domainof legal dual-use items. For example, so asnot to arouse suspicion, the calutron programimported large iron-pole magnets (4.5 meters in diameter) from a European foundry in crude, unfinished form; suchiron forgings were finished to specification in Iraq. The Iraqis obtained the design for buildings at the Ash-Sharqatnuclear facility that were planned to house calutrons by duplicating the Yugoslav-built Tarmiya site. 3Iraq did indeed have a major petrochemical industry, which helped provide cover for its nuclear-weaponprogrampurchases. However, at least three other factors also helped shield its foreign procurement ofnuclear-related dual-use items from drawing too much attention. First, tensions among IAEA member states in theMiddle East following the Israeli bombing of the Osirak reactor made it harder for the IAEA to be as proactive withrespect to Iraq as it might otherwise have been. 4 Second, Iraq’s war with Iran could arguably have been placingheavy demands on certain technologies that needed replenishment through imports. And finally, the United States1 Mum of the material in this box is based on discussions with David Kay, head of several IAEA nUOlOarinspections in Iraq oarried out under the auspices of U.N. Resolution 687, and his presentation at the NationatInstitute of Standards and Technology (NIST), Gaithersburg, MD, May 15, 1992.2 David t(ay, pmsentatkm at NIS~ May 15, 1892, op. dt., footnote 1; from his dhcusslon *th Jaffar *dn9one of the early IAEA inspections in 1991.3 Jay c. Davis and David Kay, “Iraq’s Secret Nuolear %pOn pr~ram,” PhYScs T~aY, JUIY 1~2/ ~“21-27.4 Osirakwas not yet operating at the tlmeof the attaoh but had already been plaoed under IAEA Safquards,which would have inoreased in scope onoe the reactor became operational. Furthermore, French teohnlcians hadbeen present at the reactor since 1978, and were scheduled to remain for years.

Chapter 4-Technical Aspects of Nuclear Proliferation | 169and other Western nations’ tilt toward Iraq in the Iran-Iraq war gave Iraq many “green lights” for importingtechnologies that might otherwise have caused more concern?The Iraqis also apparently had some success at foiling western National Technical Means (NTM) ofverification. The Tarmiya site, for instance, which housed the main EMIS facility, had no security fence and novisible electrical capacity; only later did inspectors discover that it was powered by a 30-kV underground electricalfeed from a 150 MWe substation several kilometers away. Tarmiya was also situated within a large military securityzone, thereby needing no additional perimeter security or military defenses at the site. 6 At this same site, the Iraqisbuilt a multimillion-dollar “chemical wash” facility for recovering uranium from refurbished calutron components.This facility was reportedly as sophisticated and dean as any in the West, and triple-filtered so as not to releaseany trace of effluents into the atmosphere that might have led to its detection once it began operation.5 For instance, electron-beam welding machines were being imported under the justification of reP~dn9tanks and jet engines. This explanation was accepted by western countries, despite the utility these machines hadfor certain nuclear technologies. A U.S. oompany also reportec9y sold Iraq a sophisticated milling machine withoutits export-restricted laser-alignment module, but then suggested that the latter be purchased from the tmmpany’sGerman subsidiary, where less-stringent export controls were in effect. David Kay, presentation at NIS~ op. cit.,footnote 1, May 15, 1992.6 Thatthg Tarmiyafacility Indeed hwsed a substantial piece of the Iraqi nuclear program W- only ~nfir~dafter the Gulf War in the early summer of 1991, when the movement thereof large saucer-like objects (just prior tothe first IAEAinspection of the site) led to the positive identification of the Iraqi calutron program. cf. Davis and Kay,“Iraq’s Secret Nuclear VWapons Program,” op. dt., footnote 3, p. 24.characteristic double flash of light from abovegroundnuclear tests anywhere in the world. Otherkinds of satellite imagery might also be used todetect chilling equipment or surface changesassociated with underground tests, possibly evenchanges caused by the shock waves from the testitself. l24Seismic signaturesIf a country chooses to use undergroundnuclear explosive tests to further a weaponprogram, seismic disturbances would provideanother telling signature. Nuclear tests withexplosive yields above 10 kt in almost any regionof the world would be very difficult to hide fromexisting seismic networks and other nationaltechnical means of verification. 125 Similarly, testswith yields down to about 1 kt would likely bedetectable if there were a comprehensive worldwidenetwork of seismic stations coordinated forthe task. 126Much work has been done to analyze evasiontechniques and the potential use of seismic wavesto distinguish low-yield nuclear tests from earthquakesand chemical explosions. One evasionmethod is called “decoupling,’ whereby explo-1~ For ~tam, the locatiom of nuclear explosion under Degelen Mountain in the Soviet Kazakhstan test site have been shown to beckz@visible through color changes associated with the shock-wave-caused spallation of rocks fkom the mountain above them. William Leith andDavid W. SimpsoU “Monitoring Underground Nuclear ‘Rxts, “ in Commercial Observation Satellites and International Secur@, MichaelKrepoL Peter Zimmermiq bonard Spector, and Mary Umberger, MIs., (New York NY: St. Martin’s Press, 1990), p. 115.1~ U.S. ConWess, office of nchnolo=~sesment, Seismic Verification ofNuclearTesring Treaties, OTA-ISC-361 (Washington DC: U.S.Government Printing Office, May 1988), p. 13,lx hid. For instanm, with a system of tens of seismic stations distributed in and around the U.S. and former Soviet UniO14 nUCIm tests inthose countries with no attempt to muffle the seismic signals could be detected and identifkd down to 0.1-0,5 ~ similar coverage in the southernhemisphere or worldwide would require a corresponding worldwide seismic network. Decoup/edexplosiom, or ones conducted in a large cavityto reduce the seismic waves they cause, could similarly be detected and identified down to yields of several kt to 10 kt. Also see Prof. LynnSykes, Lament-Doherty Geological Observatory, Columbia University, presentation at the conference sponsored by the IRIS Consortium, TheProl$eration of Nuclear Weapons and the Role of Underground Testing, Princeton University, Nov. 12, 1992.

170 I Technologies Underlying Weapons of Mass Destructionsions are carried out in large underground cavities.127 However, preparations for decoupled testsmight be observed by the amount of excavationrequired. 128 Another scheme involves hiding thesignal of a nuclear test in the aftershocks of anearthquake. However, the seismic signals ofearthquakes are known to differ in detectableways from those of nuclear explosions, andexploiting them might require delaying a testdetonation for weeks or longer, poised to explodewithin seconds of a suitable earthquake. 129 Successfulevasion scenarios for nuclear tests, therefore,appear not to be very credible, especially fora nation with limited resources or experience insuch areas.Atmospheric releases from underground testsUnderground nuclear tests, even at sub-kilotonyields, generate radioactive gases at extremelyhigh temperatures and pressures. Even under thebest of circumstances, some of the radioactivityproduced by underground explosions may stillescape into the atmosphere through seepage orespecially through controlled purges or ‘‘drillback’sampling to gather further data about theexplosion. In the worst case, a massive ‘venting’of the underground test would produce a plume ofgas containing millions of curies of radioactivedebris rising thousands of meters into the air. 130Even if a country has considerable undergroundtesting experience, massive releases can stilloccur; the ‘‘Des Moines’ test at the Nevada TestSite on June 13, 1962–-a test carried out in atunnel about 200 meters into the side of amountain-unexpectedly vented such an enormouscloud of debris (11,000,000 curies) that it reportedlycaused a near-panic among test-site workerswho rushed to drive away from a mountain-sizeradioactive cloud that formed above the test siteand began blowing toward them. 131 Prior to thistest, the United States had already accumulatedexperience from several dozen shaft or tunneltests carried out at the Nevada Test Site in 1958and 1961-62. If a clandestine test site in anothercountry were suspected, and if timely accesscould be gained near the site, radioactive productscould be monitored by aerial or ground sampling.Small amounts of specific gases produced byunderground tests might also be detected at closerange by exploiting their light-scattering propertieswhen illuminated by lasers.Nuclear-test-site preparationRegardless of whether a country chooses to testa nuclear device at full yield or at reduced yields,a suitable underground site would be highlydesirable. Since underground tests can be containedquite effectively when carried out properly,test-preparation activities would often be moreobservable than would atmospheric releases fromtests themselves. Drilling rigs, sections of one-meterdiameteror larger pipe, mining operations, orroad construction in new remote locations couldall indicate such preparations and could probablybe observed by reconnaissance satellites. (Determiningthat such activities actually do pertain tonuclear testing, however, may prove more difficult.)Contacts with foreign firms having experilZ7me possibility r~~ that d~oupled tests below 1 to 2 kt would not be readily identifiable as nuclear tests, even if they could bemonitored and detected by an enlarged worldwide seismic network. OTA, Seismic Verification oflhdear Testing Treaties, op. cit., footnote125, p. 14.lx me &meter of the cavi~ needed to decouple a l-kt detonation in rock for instance, is roughly 40 meters, md it sales u tie onetidpower of the yield, O’IA, Seismic Verification of Nuclear Testing Treaties, op. cit., footnote 125, p. 100.129 Distinguis~g between e~@~es and nuclear tests depends somewhat on the strength of their SeiSIniC Si@; fOr nuclear teStS Widlyields below about 1 k~ discrimi.rmtion can become very difficult.130 u.S. Congms, Office of ‘lkchnoIogy Asses,smen~ The Containment of Underground Nuclear E.@osions, OTA-ISC-414 (wmmo~DC: U.S. Government Printing Office, October 1989), p. 4, 33.131 J~ Cwotiers, ~lce of Hisl:ory and Historical Records, Lawrence Livermom National Laboratory, presentation at the ~S conference,Nov. 12, 1992, op. cit., footnote 12!6.

Chapter 4-Technical Aspects of Nuclear Proliferation | 171maintenance, handling, and deployment. Observablemight include construction of maximumsecuritystorage facilities or operational exercisesreflecting the special requirements for handlingnuclear weapons. Aircraft training runs for deliveringnuclear weapons might exhibit unique flightprofiles designed to give the pilot time to escapethe effects of the blast. Military doctrine governinguse of nuclear weapons would have to bedeveloped and integrated into the commandstructure of appropriate forces. A greater numberof people might thus learn of the weapons’existence, adding to the chance that humansources might reveal it.Nevada test site location in 1966 prior to anThe difficulty of producing fissile materials,underground nuclear test, Large drilling equipment,cranes, heavy electrical cables, and roads could all however, limits the rate at which a proliferantprovide visual indicators of such a test site.could field nuclear weapons. If only a very smallnumber of weapons were at hand, they might beence in large-hole drilling technology (for in- reserved for strategic rather than battlefield use,stance, through experience with nuclear testing thus reducing the need to conduct military exerprogramsin the United States or elsewhere) might cises that anticipated combat in a nuclear environalsobe indicators. Electronic data-acquisition ment. Furthermore, the weapons might be storedsystems, which are widely available around the unassembled and their components kept at variworld,would require extensive cabling systems ous locations. They might also be kept under thesuitable for transmitting diagnostic signals and control of a small military or quasi-military unitmight also be visible.outside of the regular military forces. It thereforemight be very difficult to detect a nuclear force| Deployment, Storage, and Maintenance of still in its infancy solely by relying only onNuclear Weaponsobservable changes in deployment, storage facili-A country interested in possessing not just one ties, or military operations. Materials productionor two but a small arsenal of nuclear weapons would still provide the greatest opportunities forwould have to make preparations for their storage, detecting such a program.

Appendix 4-AComponents, Design,and Effectsof NuclearWeaponsAnuclear weapon is a device that releases largeamounts of explosive energy through extremelyrapidly occurring nuclear reactions.Nuclear fission reactions occur when a heavyatomic nucleus is split into two or more smaller nuclei,usually as the result of a bombarding neutron butsometimes occurring spontaneously; fusion occurswhen lightweight nuclei are joined, typically underconditions of extreme temperature and pressure. Nuclearweapons utilize either fission or a combination offission and fusion.A nuclear explosive device is normally made up ofa core of fissile material that is formed into a‘‘super-critical mass’ (see below) by chemical highexplosives (HE) or propellants. The HE is exploded bydetonators timed electronically by a “fuzing” system,which may use altitude sensors or other means ofcontrol. The nuclear chain-reaction is normally startedby an “initiator” that injects a burst of neutrons intothe fissile core at an appropriate moment. lFission devices are made with highly enricheduranium-235 or with plutonium-239, which is pro-duced in nuclear reactors through neutron bombardmentof uranium-238, 2 Uranium-233, which is producedin reactors fueled by thorium-232, can also beused to construct a fission device.In fission weapons, energy is released through anexplosive chain reaction that occurs when neutronbombardednuclei split and subsequently emit additionalneutrons. 3 These additional neutrons sustain andmultiply the process in succeeding fission reactions or‘‘generations. The minimum mass of fissile materialthat can sustain a nuclear chain reaction is called acritical mass and depends on the density, shape, andtype of fissile material, as well as the effectiveness ofany surrounding material (called a reflector or tamper)at reflecting neutrons back into the fissioning mass.Critical masses in spherical geometry for weapongradematerials are as follows: 4Uranium-235Plutonium-239Bare sphere:. . . . . . . . . . . 56 kg 11 kgThick U Tamper. . . . . . . 15 kg 5@I At a presentation zt the South Mkicau Embassy, Washington, DC, on July 23, 1993, Waldo Stumpf, chief executive officer of the AtomicEnergy Corporation of South Afi_ica, Ltd., stated that South Africa designed a gun-type weapon using HEU that employed no neutron initiator.2Uranium-235 is the only naturally occuning isotope that is “fissile,” “I.e., able to be fissioned by neutrons of any speed, Its concentrationin mtural uranium (most of which is uranium-238) is only about 0.71940.s The amount of energy ultimately released is given by Einstein’s relation E=m&, where c is the speed of light and m is difference in massbetween the original nucleus and that of alt the pieces into which it is spit.4Robert Serbcr, The bsAlamos Primer: First Lectures on How to Build unAtomic Bomb (Berkeley, CA: Univ. of California Press, 1992),p. 33.I 173

174 I Technologies Underlying Weapons of Mass DestructionTwo basic designs to assemble a supercritical massof fissile material are gun-assembly and implosion. Inthe gun-assembly technique, a propellant charge propelstwo or more subcritical masses into a singlesupercritical mass inside a high-strength gun-barrellikecontainer. Compared with the implosion approach,this method assembles the masses relativelyslowly and at normal densities; it is practical only withhighly enriched uranium. (If plutonium—even weapongrade-wereused in a gun-assembly design, neutronsreleased from spontaneous fission of its evennumberedisotopes would likely trigger the nuclearchain reaction too soon, resulting in a ‘‘fizzle’ ofdramatically reduced yield. See box 4-B on reactorgradeplutonium in main text.)In the implosion technique, which operates muchmore rapidly, a shell of chemical high-explosivesurrounding the nuclear material is designed (forexample, by being detonated nearly simultaneously atmultiple points) to rapidly and uniformly compress thenuclear material to form a supercritical mass. Thisapproach will work for both uranium and plutoniumand, unlike the gun-assembly technique, creates higherthan normal densities. Since critical mass decreasesThe “mushroom cloud” of hot gases and radioactiverapidly as density increases (scaling as the inversedebris caused by a nuclear detonation near the groundcan rise upwards of tens of thousands of feet and square of the density), the implosion technique canspread dangerous radioactive fallout far downwind. make do with substantially less nuclear material thanthe gun-assembly method.Significant quantities of nuclear materials have beendefined by the International Atomic Energy AgencyIn both types of designs, a surrounding tamper may(IAEA), which is charged with ensuring that thesehelp keep the nuclear material assembled for a longermaterials not be diverted from peaceful uses intotime before it blows itself apart, thus increasing theyield. The tamper often doubles as a neutron reflector.weapons (see app. 4-C and table 4C-3 on significantIn a fission weapon, the timing of the initiation of thequantities). These thresholds, which the IAEA considerssufficient for processing into a weapon, are 8 kg ofchain reaction is important and must be carefullydesigned for the weapon to have a predictable yield. Aplutonium (total element) or 25 kg of the isotopeneutron generator emits a burst of neutrons to initiateuranium-235 in highly enriched form (uranium containing20 percent or more of the isotope uraniurn-the chain reaction at the proper moment—near thepoint of maximum compression in an implosion235). 5 A first-generation fission weapon developed bydesign or of full assembly in the gun-barrel design.a state without much experience at nuclear weapondesign would most likely have a yield in the range of Using these approaches, a substantial fraction of a1 to 50 kilotons. 6 weapon’s fissile material would probably be blowns If one could assemble 8 kg of plutonium into a sphere, it would have a diameter of about 9.2 crrL somewhat bigger than a baseball; 25kg of uranium would have a radius about 1.5 times larger.b A kiloton (M) is defined as 4.18 x 10 12 joules, which is approximately the energy released in the explosion of a thousand tons of TNT.

——Appendix 4-A-Components, Design, and Effects of Nuclear Weapons I 175apart before it fissioned. To fission more of a givenamount of fissile material, a small amount of materialthat can undergo fusion, deuterium and tritium (D-T)gas, can be placed inside the core of a fission device.Here, just as the fission chain reaction gets underway,the D-T gas undergoes fusion, releasing an intenseburst of high-energy neutrons (along with a smallamount of fusion energy as well) that fissions thesurrounding material more completely. This approach,called boosting, is used in most modem nuclearweapons to maintain their yields while greatly decreasingtheir overall size and weight.Fusion (or ‘‘thermonuclear’ weapons derive asignificant amount of their total energy from fusionreactions. The intense temperatures and pressuresgenerated by a fission explosion overcome the strongelectrical repulsion that would otherwise keep thepositively charged nuclei of the fusion fuel fromreacting. In general, the x-rays from a fission “primary”heat and compress material surrounding a“secondary” fusion stage. 7 Such bombs, in theory,can be designed with arbitrarily large yields: the SovietUnion once tested a device with a yield of about 59megatons.EFFECTS OF NUCLEAR WEAPONSThe massive amounts of energy released by bothfission and fusion explosives generate blast, heat, andradiation. Blast effects include shock waves, overpressure,and intense winds. Heat is released in the form ofinfrared and visible radiation which, for large-yieldweapons detonated under the right conditions, cancause firestorms in cities well beyond the region ofheavy blast damage. 8 Radiation effects include theprompt bursts of gamma rays and neutrons, theproduction of radioactive fission products and, if theexplosion’s fireball touches the ground, significantamounts of fallout of radioactive materials formedfrom or condensed upon soil that is swept up into themushroom cloud. 9 Taking into account all of theseeffects except fallout, the effective lethal radius 10 fora l-kt fission weapon is approximately 0.7 km (area1.5 km 2 ), for a 20-kt fission weapon 1.8 km (area 10km 2 ), and for a l-Mt hydrogen bomb 7-13 km (area150-600 km 2 ), depending on the occurrence of firestorms.llT The secondary usually contains solid lithium-6 deuteride. (Lithium-6 creates tritiurn when bombarded by neutrons produced during thedetonation.) As in fission weapons, the liberated energy is refleeted in the change in total mass during the reaction.B Willim Daugherty, Barbara Uvi, and Frank von HiP@, “The Consequences of ‘Limited’ Nuclear Attacks on the United States,”International Security, vol. 10, No, 4, spring 1986, p. 15.g A nuclear weapon detonated at high altitude can also generate a powerful pulse of radio waves (called “electromagnetic pulse’ ‘), whichcan wreak havoc on some types of electronic equipmen$ but would not pose a direct human health risk.10 Here, .#ec~ive lethal r~ius describes a circular area around ground zero for which the number of p~ple reskhg in the circle (Ushguniform population density) is the same as the total number of people that would be killed under normal conditions by the immediate effectsof the explosion. Alternatively, it describes the radius at which the fatality rate, given a typical amount of shielding for an urban ar% isapproximately 50%0.]] s=, for exmple, Dietrich sc~mer, Science, Technology, and the Nuclear Arms Race (New York ~: Jo~ WdeY & SOIIS* 1984)> P.47 (figure 2.9).

Appendix 4-BEnrichmentTechnologiesThis appendix describes several approaches bywhich the uranium-235 isotope used in nuclearweapons can be separated from themore common uranium-238. Enrichmentplants based on these approaches generally consist ofa number of individual stages, each of which takes aninput source of uranium, or “feed,’ and produces twooutputs: one with a greater concentration of uranium-235 than the feed (the “product”), and the otherdepleted in uranium-235 (the “tails”). The separationfactor indicates how much enrichment each stageprovides. (It is defined as the relative isotopic abundanceof uranium-235 of the product divided by that ofthe tails.)Tables 4-4 through 4-7 in the main text summarizeand compare attributes of various enrichment approaches.The descriptions below are illustrative, butby no means exhaustive, of the isotopic enrichmentmethods known to have been supported by substantialresearch or development programs. Not included aremany completely different techniques that have beenproposed, some of which have undergone preliminaryresearch. lURANIUM AND ITS PROPERTIESSeveral different chemical compounds of uraniumare used in enrichment processes, all of which aredifficult to handle. Although calutrons used by theUnited States during World War 11 and by Iraq in thelate 1980s utilized UCl 4feed to make ion beams, themost important feed material for enrichment is UF 6, acolorless solid at room temperature that sublimes at56.5 “C. UF 6is used in gaseous diffusion, centrifuge,aerodynamic, MLIS and, in its liquid state, thermaldiffusion processes. It is highly corrosive to manymetals and generally requires special nickel or aluminumalloys to process it. It also reacts violently withwater and with many organic compounds such as oilsand lubricants, so that handling systems must beextremely clean and free of leaks. Chemex processes(see below) normally use simple uranium compoundsin hydrochloric acid solution.In its elemental form, uranium is a silvery-whitemetal which, when finely divided in air, ignitesspontaneously and, when in its atomic vapor state, ishighly corrosive to many materials. AVLIS andplasma processes use atomic uranium. The ion beam1 Examples of some of the others can be found in Allan S. Krass et al., Uranium Enrichment and Nuclear Weapon Proliferation (London:Taylor & Francis, Ltd., 1983), pp. 171-2, 186-7, and references therein.I 176

Appendix 4-B–Enrichment Technologies I 177used in EMIS, though produced from UCI 4, is alsoelemental uranium.THERMAL DIFFUSIONThe uranium compound UF 6in its liquid state issubjected to strong temperature differences to separatethe heavier (uranium-238) isotope from the lighter one(uranium-235). The United States developed thisprocess before WWII using concentric tubes, cooledon the outside wall by water and heated on the insideby steam; in the region between the tubes, the lighterisotope very slowly tended to concentrate near theinner wall and rise, whereby it was removed. Theseparation factor is no more than about 1.0003, andonly very low enrichments are possible. 2 In 1944,2,100 such tubes-each almost 15 m high-producedenrichments of only about 0.9 percent uranium-235(starting from natural uranium with about 0.71 percenturanium-235) to feed the U.S. calutron program. 3Thermal diffusion is not known to have been used onany significant scale since World War II.GASEOUS DIFFUSIONUF 6in its gaseous state is forced through a suitableporous barrier that preferentially passes the lightermolecules containing uranium-235, which travel onaverage a little faster and diffuse through the barrierslightly more efficiently. Gaseous diffusion is a proventechnology, but requires an enormous amount ofelectricity to operate its pumps and compressors.Moreover, to produce significant quantities of enrichedmaterial, cascades must have thousands ofstages, each stage having many elements or chambers.A cascade requires up to weeks between start-up andthe point when it first produces appreciable amounts ofenriched uranium (and months or longer to reachequilibrium). Therefore, ‘batch recycling ‘—the processof reintroducing an enriched product as new feedstock into a cascade designed to produce LEU fromnatural uranium-is a relatively unattractive means ofachieving higher enrichments. The U.S. gaseous diffusionplant at Oak Ridge made only a small contributionto the uranium enrichment effort during World War II,but the diffusion technology soon came to dominatethe field.GAS CENTRIFUGEPrecision high-speed rotors containing UF 6gas spinwithin vacuum chambers. Heavier isotopes concentratepreferentially near the rotor’s wall and are madeto convect upwards, where they can be scooped out.New high-strength lightweight materials, such ascarbon- or glass-fiber bonded with resins allow modemcentrifuges to spin at extremely high speeds. 4Cascade equilibrium times are measured in minutes totens of minutes. This technology is widely used inseveral countries in Europe and in Japan, and has alsobeen developed in the United States.Attractive for proliferation in almost every respect(economical, efficient, widely dispersed proven technology,easily capable of high-enrichment, etc.),modern centrifuge technology is classified and isconstrained by strict export controls. 5 Even so, Japan,Pakistan, India, and Brazil have each been able to buildgas centrifuge cascades, and Iraq and South Africa hadpurchased many components in spite of export controls.All of these have been URENCO-type moderncentrifuges, which are at least 20 times more productivethan those designed by Gemot Zippe in the SovietUnion in the late 1940s. By the late 1950s, the SovietUnion adopted Zippe’s basic design and went on todevelop centrifuge technology to a production scale.(In 1942-43 during the Manhattan Project, the UnitedStates also considered using early-design centrifuges,but rejected them because of mechanical problems.)2Separation factor is defined as ratio of the relative (uranium-235 to uranium-238) enrichment of the product stream to that of the tails orwaste stream in any one stage of a cascade.3 SW Rictid H modes, The Making ~~ the AtOmic B~~ (New York, ~: Simon & Schuster, 1986), pp. 552-4; ~d Manson Benedictand Thomas H. Pigford, Nuclear Chemical Engineering, 2nd ed. (New York NY: McGraw-Hill, 1989), pp. 498-508. Even this smallenrichment made a useful contribution to the productivity of the calutrons.4 Alurnin urn and titanium rotors are only strong enough to run at moderate speeds; maraging steel—a particularly strong low-carbon alloy,typically consisting of at least 10% nickel plus cobalt, molybden~ and other alloying agents-allows moderately high speeds. See Krass etal., Uranium Enrichment. . . . op. cit., footnote 1, pp. 132.5Designs for low speed (subcritical) ahunin urn-alloy centrifuges of the type developed by Gemot Zippe up to 1960, however, are anexception and are not classified.

178 I Technologies Underlying Weapons of Mass DestructionAERODYNAMIC PROCESSESA carrier-gas and isotope mixture is forced at highspeed through a curved nozzle or vortex, allowingcentrifugal force to concentrate the heavier isotopesnearer the outer portion of the flow where they can thenbe separated by a skimmer. Due to low separationfactor (intermediate between gaseous diffusion andcentrifuges) and high energy consumption, aerodynamicprocesses are economically not very attractive,but could be configured in modular cascades in arelatively small facility for a weapon program.CHEMICAL EXCHANGE PROCESSESLow-energy, low-maintenance chemical-exchangeseparation methods are based on chemical reactionsthat exhibit a slight preference for one uranium isotopeover the other. Two methods known to have beendeveloped to date are the Japanese Asahi ion-exchangeprocess, which requires a proprietary resin, and theFrench solvent-extraction (Chemex) process. Both usespecial chemicals in the liquid state. 6 The Asahiprocess requires a specific catalyst and is limited by themixing times of the reagents and the reticulated resin,but with the catalyst present the chemical exchangeoperates very rapidly. The French process does notrequire an exchange catalyst and is limited only by themixing dynamics, but it must avoid impurities that cancatalyze unwanted reactions. Because of the very lowseparation factor, up to thousands of stages can berequired even to reach LEU; however, since a singlephysical item (e.g., an ion exchanger or pulse column)can contain tens or hundreds of effective “stages,”these large numbers can be misleading. Both processeshave been put through pilot-plant operations that haveproduced the expected enrichments at costs that wouldbe economical on a commercial scale. 7In part because LEU made with chemical separationmight permit other enrichment approaches to reachhigh enrichments more readily than they would if fedwith natural uranium, France has offered to sell itsChemex process to countries only on the condition thatthey not pursue any other enrichment paths.LASER PROCESSESThese methods include Atomic Vapor Laser IsotopeSeparation (AVLIS), Molecular-vapor Laser IsotopeSeparation (MLIS), and Laser-Assisted Processes(LAP) such as “Chemical Reaction by IsotopicSelective Activation” (CRISLA). All utilize smalldifferences in the frequencies of light that atoms ormolecules of different isotopic masses will absorb.Laser processes in general must induce several atomicor molecular interactions (excitations, ionizations, orchemical reactions) in succession, requiring severallasers to act in concert. Laser frequencies must betuned very precisely-usually to an accuracy of about1 part in 1,000,000. 8 Maintainin g such precise tuningat high power levels is one of several key technicalobstacles faced by laser processes.AVLIS, as developed at the Lawrence LivermoreLaboratory, uses laser radiation to selectively strip anelectron off atoms of uranium-235, but not uraniurn-238, in a uranium metal vapor at high temperatures andlow density. MLIS uses tuned laser light analogous toAVLIS to selectively excite an electron in 235 UFG (butnot238UF molecules and then to remove one fluorineatom. CRISLA’s inventors claim that they have aproprietary compound that functions as an intermediary,selectively reacting with laser-excited 235 UF 6molecules. (This has not been independently confirmed,however.) Although MLIS and CRISLAreaction rates are both hindered by unwanted molecularcollisions competing with desirable laser-excitationprocesses, the CRISLA process may have the addedcomplexity of needing a particular collisional excitationto win out over the others.Laser processes are still in development, and tests sofar have been conducted only in the laboratory or insmall pilot-plants. Because of their potential to producehigh enrichments in a single step and their lowenergy use, they could eventually prove to be veryefficient. Some of the equipment associated with laserprocesses is not subject to export controls and couldprobably also be developed-at least on a laboratoryscale-by countries such as Israel, India, and Brazil.b If high enrichment levels are to be produced, great care must be taken to avoid the formation of a critical mass of material anywhere withinthe facility. Criticality with liquid and solid-phase methods is much more of a concern than with methods using gaseous forms of uranium.7John M. Googin, senior staff consultant Martin Marietta Energy Systems, Inc., private communicatiorq Aug. 11, 1993.s AVLIS uses pumped dye lasers, MLIS uses C0 2infrared lasers and possibly xenon-chloride excimer lasers operating in the ultravioletand CRISLA uses CO infrared lasers.

Appendix 4-B–Enrichment Technologies I 179disassembled. They also require a precisely controlledhigh-voltage vacuum-ion source (now subject toexport controls under the 1992 Nuclear SuppliersGroup dual-use guidelines) and strong, uniform electromagnets.(Ions are atoms with an electron removed,giving them a positive net electrical charge.) Ions ofdifferent masses are separated by exploiting thedifferent curvatures of the paths they take whentraveling through magnetic fields. Electromagneticmethods are also useful for separating plutoniumisotopes, a task otherwise practical only through laseror centrifuge techniques. 10Laser equipment that could be used for research anddevelopment of laser isotope separation (LIS)techniques. LIS methods are among several advancedtechnologies that may eventually lead to more efficientways of enriching uranium.Nevertheless, the required laser and material-flowtechnologies-especially at the scale needed for commercialoperation—are highly sophisticated, and theirintegration poses a number of very serious difficulties.9 However, in early 1992 the South AfricanAtomic Energy Corporation announced that it wasplanning to begin operating one unit of a MLIS pilotenrichment facility in 1994, and a similar pilot-scalefacility is being built in Japan. An AVLIS pilot plantis also under construction in the U.K.ELECTROMAGNETIC PROCESSESThis group of technologies includes EMIS (calutrons),ion cyclotron resonance, and plasma centrifugemethods. Although theoretically as capable aslaser processes at producing high enrichments with asmall number of stages, these are — with the exceptionof the calutron—still in the experimental stage. Allwould require frequent maintenance, since the enrichedproduct accumulates in collectors that can onlybe accessed when the system is turned off and partially| CalutronsCalutrons send high-voltage ions through a halfcircleof rotation in a strong magnetic field inside alarge disk-shaped vacuum chamber. They are veryenergy-inefficient, costly, bulky, and require a greatdeal of maintenance. Developed and used by theUnited States during World War II, their design wasdeclassified decades ago.Since higher separation factors require lower beamdensities, up to several hundred calutrons could berequired to produce enough HEU for a single bomb peryear. However, use of even slightly enriched feeddramatically increases a calutron’s production rate,thereby reducing the number of units needed. The Iraqienrichment program relied primarily on calutrons.| Ion Cyclotron ResonanceIon cyclotron resonances techniques rely on theroughly 1 percent difference in frequency at which ionsof different uranium isotopes orbit in a magnetic field.This difference allows precisely tuned radio waves toselectively energize one isotope over the other. Theselected ions will absorb radio energy and orbit in everlarger spirals, eventually colliding with a downstreamset of collector plates. Other isotopes are not affected,and most will pass through the gap in the plates. Keydifficulties are that the process requires extremely9For instance, between 1973 and 1990, the U.S. Department of Energy invested almost $1 billion in AVLIS developmen~ but producedonly kilogram quantities of 1 YO enriched uranium. In 1990 it had planned to build a 100,000-250,000 SWU/yr pilot plant that might have begunoperation in 1992, but the idea has now been practically abandoned.10 me Plutoniu isotopes of interest are closer in mass than uranium isotopes and hence harder to sepmte.

180 I Technologies Underlying Weapons of Mass Destructionokmetallic uranium can also be problematic. This enrichmentprocess has been demonstrated with modest sizeunits, but is not projected to become commerciallycompetitive.Iraqi electromagnetic isotope separation (EMIS)equipment, here being uncovered by IAEA and UnitedNations inspectors, had been hidden in the desertfollowing the Persian Gulf War.uniform magnetic fields, usually calling for superconductingmagnets, and a suitable electromagnetic signalor wave. In large machines, producing ions from| Plasma Centrifuge SeparationPlasma centrifuge separation, in contrast to ioncyclotron resonance, requires an ionized gas (orplasma) to be created that is dense enough to undergofrequent internal collisions. If injected perpendicularto a magnetic field, such a plasma will forma ring androtate. As the isotopes to to equalize in velocity, theheavier isotopes will tend to concentrate toward theouter portion of the ring where they can be removed(analogous to gas centrifuges). This is probably theleast developed of the electromagnetic methods, andmay use substantially more energy and achieve a lowerenrichment factor than ion cyclotron resonance. It mayalso suffer from instabilities and other operationaldifficulties.

.Appendix 4-CSafeguards andthe CivilianNuclearFuel CycleAs of the end of 1992, there were 424 commercialnuclear power reactors in operationin 29 countries, producing 330 GW ofelectricity (see table 4C-1). 1 About 75 percentof these are light-water reactors (LWRs) fueled bylow-enriched uranium (LEU) containing 3 to 4 percenturanium-235. Most of the remainder are fueled bynatural uranium and are moderated by either heavywater (CANDU-type reactors) or graphite. 2 SomeLWRs in France, Germany, and Switzerland have nowbeen loaded with mixed plutonium-uranium oxide(MOX) fuel, which replaces about a third of their cores.(Japan and Belgium also have plans to fuel LWRs withMOX.) Several breeder reactors fueled by plutoniumhave also been built, but the majority of them havebeen shut down in recent years.The low-enriched or unenriched fuel supplyingalmost all of these reactors is not a direct proliferationthreat. However, all nuclear reactors are theoreticalsources of material for nuclear weapons, since plutoniumis produced in reactors fueled by uranium, andthe fresh low-enriched fuel used in LWRs would beconsiderably easier than natural uranium to transforminto HEU. 3 If not adequately safeguarded, the fuelcycle and facilities associated with power reactorsprovide a number of points from which relevantmaterials could be diverted.So far, no nuclear facilities under full-time IAEAsafeguards are known to have produced fissilematerial used in nuclear explosives. The five nuclearweapon states have each used dedicated facilities tomake weapon materials. The several states thought tohave prepared weapon-usable material outside or inviolation of safeguards commitments have primarilyused either small reactors coupled with unsafeguardedpilot reprocessing plants (e.g., India, Israel, and North1 These figures do not include 72 reactors under construction in these plus another three countries, or any research reactor~f which thereare about 325 in over 50 countries. Half of these research reactors are in the five nuclear weapon states. The number of power and researchreactors has remained nearly constant since the middle 1980s, with slightly more reactors having been decommis sioned or shut down sincethat time than brought online.2The moderator in a nuclear reactor S1OWS down the neutrons produced in fission r~tions so that they can more efllciently inducesubsequent fission reactions.3Uranium-233 (another weapon-usable material) is produced in reactors that contain thorium, but few reactors based on a thorium fuel-cyclehave ever been built.I 181

182 I Technologies Underlying Weapons of Mass DestructionArgentina. . . . . . . . . . . .Belgium. . . . . . . . . . . . .Brazil.. . . . . . . . . . . . . .Bulgaria . . . . . . . . . . . .Canada. . . . . . . . . . . . .China. . . . . . . . . . . . . . .Cuba. . . . . . . . . . . . . . .Czech Republic. . . . . .Finland. . . . . . . . . . . . .France. . . . . . . . . . . . . .Germany. . . . . . . . . . . .Hungary. . . . . . . . . . . .India, . . . . . . . . . . . . . .Iran. ., . . . . . . . . . . . . .Japan. . . . . . . . . . . . . .Kazakhstan, . . . . . . . . .Korea, Rep. of. . . . . . . .Lithuania. . . . . . . . . . . .Mexico. . . . . . . . . . . . . .Netherlands. . . . . . . . . .Pakistan. . . . . . . . . . . . .Romania. . . . . . . . . . . .Russian Federation. . .South Africa. . . . . . . . .Slovak Republic. . . . . .Slovenia . . . . . . . . . . . .Spain. . . . . . . . . . . . . . .Sweden. . . . . . . . . . . . .Switzerland. . . . . . . . . .United Kingdom. . . . . .Ukraine. . . . . . . . . . . . .Us.. . . . . . . . . . . . . . . .Table 4C-1-Nuclear Power and Research Reactors Around the WorldPower reactorsPower reactorsin operation”under construction.No. units Total MW(e) %electric power No. units Total MW(e) Research reactors c2716211—44562149—44192121—28241912537151099355,4846263,53814,874288—1,6322,31057,68822,5591,7291,593—34,2383357,2202,760654504125—18,8931,8421,6326327,10110,0022,95212,06613,02098,79619.1 %59.3%0.6%34.00/016.4%NA—28.7%33.3%72.7%27.6%48.4%1.8%—23.8%NA47.5940NA3.6%4.9%0.8%—11.89405.9%28.7%34.6%35.97051 .6%40.0%20.6%NA21.7701—1—1222—5—529—311—518—4——163692—1,245—8811,8128161,784—7,125——1,0102,3928,125—2,5501,380654—3,15514,175—1,552——1,1885,7003,480World total:. . . . . . . . . . 424’ 9 330,918e NA 72 59,716 ~ 326NA - not availablea Data, which reflect the status as of the end of 1992 as reported by the IAEA, are preliminary and subject to change.b percentages are for 19!31, except for Russia and Slovenia, where preliminary 1992 data are US4.C Research re=tors in Operation as of May 1991, Total inciu~s one research reactor in operation under the bmmis.sion of European cOfrlrTIUtli~&,five in Taiwan, plusthefollowing (in countries that have no power reactors) :Algeria (1 ); Australia (2); Austria (3); Bangladesh (1 ); Chiie (2); Coiombia(l); Denmark (2); Egypt (l); Estonia (2); Greece (2); Indonesia (3); Iraq (2); Israel (2); Italy (6); Jamaica (1); Latvia (l); Libya (l); Malaysia(l); NorthKorea (2); Norway (2); Peru (2); Philippines (1); Poland (3); Portugal (1); Thailand (1); Turkey (2); Uzbekistan (1); Venezuela (1); Vietnam (1); andZaire (1).d Represents the average 1991 value for the Czech and Slovak Republicse The total includw Ta~an, where six reactors total[ing 4,890 MWe are in operation, amunting for 37.80A of the total electricity generated therein 1992.SOURCE: IAEA Bu//etin, vol. 35, No. 1, March 1993 and vol. 33, No. 3, September 1991; and William C, Potter, Nuclear F?ofrles of the SovietSuccessor States (Monterey, CA: Monterey Institute of International Studies, May 1993).5541141202120253621833—42222012002411292

Appendix 4-C-Safeguards and the Civilian Nuclear Fuel Cycle I 183Table 4C-2—Number of Installations Under IAEA Safeguards or ContainingSafeguarded Material as of Dec. 31, 1992INFCIRC/153b INFClRC/66 cType of installation s (Corr.) (Rev. 2) In NWS d TotalPower reactors. . . . . . . . . . . . . . . . 182172201Research reactors and criticalassemblies. . . . . . . . . . . . . . . . . 145222169Conversion plants, . . . . . . . . . . . . 73010Fuel fabrication plants. . . . . . . . . . 349144Reprocessing plants. . . . . . . . . . . 5106Enrichment plants. . . . . . . . . . . . . 5117Separate storage facilities. . . . . . 366547Other facilities. . . . . . . . . . . . . . . . 574061Subtotals. . . . . . . . . . . . . . . . . . 471 63 11 545Other locations. . . . . . . . . . . . . . . . 468 32 0 500Nonnuclear installations. . . . . . . . 0 3 0 3Totals. . . . . . . . . . . . . . . . . . . . . 939 98 11 1048a For some types of installation, predominantly reactors and soedled “other locations, ” several installations ~n beIo=ted at a single site or facility.b Covering safwuards agreements pursuant to NpT an~or Treaty of Tlatelolco; excludes locations in Iraq.c &C[uding Installations in n~lear-weapon States; including installations in Taiwan, China.d Nuclear-weapon States.SOURCE: IAEA, The Annua/ Report for 7992, GC(XXXVll)/1060 (Vienna, Austria: International Atomic EnergyAgency, July 1993), p. 149.Korea) or unsafeguarded pilot enrichment plants (e.g.,Pakistan, South Africa, and Iraq). 4The reason for the apparent preference fordedicated or unsafeguarded weapon facilities isstraightforward: the construction and operation ofnuclear power reactors and other commercialfacilities so as to divert materials to a weaponprogram is neither the easiest nor the most efficientroute to obtain nuclear weapon materials. First,more than 150 states have joined the NPT as nonnuclearweaponstates, which obligates all with nuclear facilitiesto sign and implement so-called safeguardagreements with the IAEA to provide assurance ofnondiversion of nuclear materials. (As of Dec. 31,1992, the IAEA had 188 safeguards agreements inforce with 110 states plus Taiwan. 5 See table 4C-2.)Second, the vast majority of the material in thecommercial nuclear fuel cycle is not directly suitable4See, for example, David Fischer and Paul Szasz, .Safeguarding the Atom:A CriticalAppraisal (_I.mdon: SIPRI, Taylor and Francis, 1985),p. 52; and Leonard S. Spector with Jacqueline R. Smith, Nuclear Ambitions: The Spread of Nuclear Weapons, 1989-1990 (Boulder, CO:WestView Press, 1990).S The 45 parties to the Nuclear Non-Proliferation Treaty with safeguards in force base their agreements on the IAEA documentINFCIRC/153(Corrccted)--’ ‘The Structure and Content of Agreements between the Agency and States Required in Connection with the Treatyon the Non-Proliferation of Nuclear Weapons. ” The 10 non-~ states with safeguards in force base their agreements on INFCIRC/66/Revision.2 —“The Agency’s Safeguards System” (1965, as provisionally extended in 1966 and 1968). (The term “INFCIRC” comes from‘‘Infomnation Circular. ’ In additio~ some safeguards were applied in the five nuclear weapons states under voluntary agreements.Some important non-NPT states have accepted IAEA safeguards (INFCIRC/66) on certain facilities, but rarely do these covcx key nuclwfacilities from a proliferation perspective. In order for the IAEA to determine nondiversion for a State as a whole, it must have all nuclearmaterials in a country’s fuel cycle under safeguards, a situation called fill-scope safeguards.

184 I Technologies Underlying Weapons of Mass DestructionIAEA SAFEGUARDSIAEA Board room showing participants at aninternational advisory committee meeting.Membership in the IAEA since 1957 has grown toover 100 States.for weapons and requires difficult additional steps,such as conversion, further enrichment, or reprocessing,to make it so. For instance, all handling ofcommercial spent fuel requires extensive shielding toprotect workers from lethal doses of radioactivity.Furthermore, reprocessing of that fuel yields reactorgradeplutonium, which is less desirable than otherfissile materials for making weapons. Finally, operatinglarge commercial facilities in the obviouslyuneconomic way that would be required to maximizetheir ability to produce weapon material-such as withfrequent fuel changes-would draw considerable attentionwhether safeguarded or not.IAEA safeguards are a system of procedures fornuclear material accountancy, control, and verificationthat are implemented through agreements between theIAEA and individual countries. These proceduresinvolve: record-keeping at facilities; reporting requirementsfor material transfers and inventories; standardizedmeasurements and assays; containment and surveillancemethods (using seals, cameras, and otherrecording devices); and regular onsite inspections bythe IAEA. The objective of safeguards is the timelydetection of diversion (or verification of nondiversion)of a significant quantity of nuclear materials fromdeclared peaceful activities to nuclear explosive purposes(see tables 4C-3 and 4C-4). Except for thepossibility of so-called “special” inspectionswhichhad not been used at any undeclared locationprior to the Persian Gulf War—safeguards agreementsrequire only that declared (peaceful) activitiesbe verified as being peaceful, and that thematerials they involve be accounted for; they do notrequire verification of the absence of nondeclared(possibly weapon) activities (though such activities,if discovered, would be a violation). Furthermore,even strict adherence to safeguards cannot predictfuture intent.NPT safeguards focus on nuclear materials themselvesand not on other facilities that potentially couldTable 4C-3--IAEA Significant Quantities of Nuclear MaterialsMaterial Significant quantity Safeguards apply to?Direct-use material: Pu b 8 kg Total mass of elementU-233 8 kg Total mass of isotopeU (with U-2352 20%) 25 kg Mass of U-235 containedIndirect-use material: U (with U-235 < 200/0)’ 75 kg Mass of U-235 containedThorium 20 tonnes Total mass of elementa PIUS ruIes for mixtures, where appropriate.b For pl~onium containing less than 8W0 Pu-238.c lncl~ing natural and depleted u~nium.SOURCE: /AEA Safeguards G/ossary, 1987 Ecfitiorr, IAEA/SG/lNF/l (Rev. 1), (Vienna, Austria: International AtomicEnergy Agency, December 1987), p. 24.

—Appendix 4-C-Safeguards and the Civilian Nuclear Fuel Cycle I 185Table 4C-4-Estimated Material ConversionTime for Finished Plutonium- orUranium-Metal ComponentsConversion timeOrder of days (7-10):Order of weeks (1-3) a :Order of months (1 -3):Order of one year:Beginning material formPu, HEU, or U-233 metalPU0 2 , PU(NO ~ 3) 4, or other purePu compounds;HEU or U-233 oxide or otherpure U compounds;MOX or other nonirradiated puremixtures containing Pu and U(U-233 + U-2352 20%); orPu, HEU, and/or U-233 in scrapor other miscellaneous impurecompoundsPu, HEU, or U-233 in irradiatedfuelU containing < 20% U-235 andU-233; orThoriuma This range is notdeterrnined by any single factor, but the pure pU andU rmmpounds will tend to be at the lower end of the range and themixtures and scrap at the higher end.SOURCE: IAEA Safeguatis Glossary, 1987 Edition, IAWSG/1NF/1(Rev, 1), (Vienna, Austria: International Atomic Energy Agency,December 1987), p. 24.be used to process them. 6 Materials are safeguarded atmany stages in the fuel cycle: conversion (whereuranium concentrate or plutonium, if it has beenseparated for use in fuel, may be cast into its fluoride,oxide, metal, alloy, nitride, or carbide forms); enrichment;fuel fabrication; reactor operation; spent-fuelstorage; and reprocessing. The earliest phases of thefuel cycle, however, are not subject to safeguards.These phases involve mining the raw uraniumcontainingore and “milling” it to convert it intonatural-uran“urn concentrate (U 3o 8) called yellowcake(see figure 4C-1).Few countries operate facilities that represent allstages of the fuel cycle, and some may have only asingle nuclear research reactor supplied and fueled byanother country. Nevertheless, unsafeguarded facilitiescould, in theory, be operated clandestinely alongwith safeguarded ones at any of these stages. Undersafeguards agreements for non-NPTcountries (INFCIRC/66), only certain facilities and materials are subject tosafeguards; these states can legally operate other,undeclared facilities, and process undeclared materialobtained from either their own uranium deposits orfrom other non-NPT states, outside of safeguards.In nonweapon-state NPT parties, however, therequisite INFCIRC/153 safeguards agreements do notpermit any nuclear facilities to be undeclared, even ifthey were to use only indigenously produced materials.Furthermore, in only one circumstance-which hasnever occurred-may such a state be permitted totransfer safeguarded material to a nonsafeguardednuclear facility. 7The safeguards process consists of three stages (seefigure 4C-2):examination by the IAEA of state-provided information,which covers design of facilities, inventories,and receipts for transfers and shipments ofmaterials;collection of information by IAEA inspectors,either to verify material inventories, operatingrecords, or design information or, in specialcircumstances, to clarify unusual findings; andevaluation by the IAEA of this information forcompleteness and accuracy. 8Taking into account each country and facility undersafeguards, the IAEA annually produces a SafeguardsImplementation Report (SIR) that contains qualitativejudgments on whether safeguards goals have beenfulfilled. However, these reports are not made availableexcept to the IAEA Board of Governors andmember governments.6 Facilities that are built with the express purpose of eventually containing nuclear materials, however, must be declared.T This exception covers the temporary removal of a declared amount of material from safeguards to a declared (nonnuclear weapon) n“litaryfacility, such as for submarine propulsion reactors.8See, for example, IAEA Safeguards: An introduction (Vienna: International Atomic Energy Agency, 1981), p. 19. Any discrepancy ofnuclear materials between the recorded (book) inventory and the physical inventory determined by inspections is called material unaccountedfor (MUF), When MUF exceeds the amount attributable to measurement uncertainties, the possibility of diversion exists and must be resolved,For an extensive discussion of safeguards concepts and methodologies, see also Fischer and Szasz, Safeguarding rheA tom, op. cit., footnote4; and Lawrence Sche- The International Atomic Energy Agency and World Nuclear Order (Washi.ngtoq DC: Resourees for the Future,1987), especially chapters 4 and 5.

,186 I Technologies Underlying Weapons of Mass DestructionFigure 4-Cl-Simplified Flow Diagram of the Nuclear Fuel CycleE3--”’e--’lEi3ycE3PuLEUDUT(N)!&uLEUNUDULEd--------’kersion ‘:k(Ox, M, A, C)+FuelfabricationI——LJ +? —.Spent fuel‘ - - -nReactor{ 1safeguard’ “’--/’--Nuclear material:yc yellow cakeNU natural uraniumDU depleted uraniumLEU low enriched uraniumHEU high enriched uraniumPu plutoniumSpent fuelChemical form:Ox oxideN nitrateM metalA alloyF hexafluorideC carbideSOURCE: IAEA Safeguards: An Introduction, IAE#SG/lNF/3 (Vienna: International Atomic Energy Agency, 1981),p. 17.Before Iraq was shown to have violated safeguards,no safeguards disputes had ever been referred to theU.N. Security Council. Since then, the possibility ofSecurity Council action has been raised with respect tocompelling North Korea to allow inspections of twosites suspected of containing nuclear waste. Despite itsNPT obligations eventually to do so, North Korea alsohad still not shut down one of its reactors (as of thesummer of 1993) so as to allow IAEA inspectors toexamine its core. Such inspections are necessary todetermine whether North Korea has ever producedsignificant quantities of plutonium.For reactors and fuel storage areas, material accountancyconsists of identifying and counting fuelrods and assemblies and verifying their compositionusing nondestructive assays (NDA). LWR fuel assembliesare enclosed in the reactor vessel in such a waythat the reactor must be shut down to change fuel

Appendix 4C-Safeguards and the Civilian Nuclear Fuel Cycle I 187Figure 4-C2-Verification Activities of IAEA Inspectors or of theSafeguards Analytical LaboratoryExamination of recordsState’s report‘L Comparison of records and reports1 4f h[ fItem counting—n12436INDA measurements~,uChemical (destructive)Elanalysis/ ‘,###Sample(NDA=nondestructiveassay)SOURCE: IAEA Safeguards; An /introduction, IAWSG/lNF/3 (Vienna: International AtomicEnergy Agency, 1981), p. 23.

188 I Technologies Underlying Weapons of Mass Destruction4 n=IAEA safeguards inspectors (center) checking freshfuel elements at a nuclear power plant. At suchfacilities, safeguards focus on item identification andmaterial accountancy, in part by verifying the recordsof plant operators.elements. This shutdown is time-consuming andobservable and makes the design and implementationof safeguards for LWRs particularly simple.CANDU-type heavy-water- moderated naturaluraniumreactors, and Soviet RBMK-type graphitemoderatedreactors, however, are refueled by insertingnew fuel rods while simultaneously removing oldones—a process that does not require shutting downthe reactor. Safeguarding such reactors requires muchmore frequent inspections as well as specializedequipment (e.g., automated bundle counters) to inventorythe replacement of fuel elements. Furthermore,since heavy water reactors (HWRs) can be refueledmuch more inexpensively and easily than other typesof reactor, fuel can be cycled through them quickly.Such reactors are therefore better suited than manyothers to produce weapon-grade plutonium 9 (see box4-A in main text).Once plutonium is separated, it represents muchmore of a proliferation hazard than when it is bound upwithin radioactive spent fuel. If reprocessing is done ata distant site, or separated plutonium is subsequentlytransferred to a MOX fuel-fabrication facility or backX-ray fluorescence spectrometer, which supports oneof the techniques used by the MEA to analyze samplestaken during nuclear inspections.to the country of origin, the transport of spent fuel andespecially of separated plutonium represent vulnerablepoints in the fuel cycle for diversion or theft.At “bulk-handling” facilities (such as those forenrichment, fuel fabrication, and reprocessing), samplesof material from within material balance areasmust periodically be removed and taken to an IAEAlaboratory to determine their composition. The uncertaintiesin measurement at large bulk-handlingfacilities are necessarily much larger than thoseinvolving the discrete items most often associatedwith reactors and their fuel. (Consequently, theIAEA inspects bulk-handling facilities much moreoften, sometimes stationing permanent resident inspectorsat these sites. Almost 50 percent of the totalinspection effort is expended at bulk-handling facilities,even though these represent only about 7 percentof the total number of installations under safeguards. 10 )Technologies for implementing safeguards improveddramatically during the 1980s, and with theseimprovements have come greater transparency andconfidence that the international fuel cycle is not beingused to aid proliferation. The IAEA has incorporatedcomputerized inspection reporting systems and hasimproved various methods for taking measurementsand implementing containment and surveillance techg~ ~~e~d~ Canadim re=h HWR supplied the plutonium for the device India exploded in 1974, and a French-supplied HWRhas been the source of unsafeguardcdplutonium in Israel. Similar but safeguurdedHWRs had been involved in suspect activities in South Koreaand Taiwan before the U.S. persuaded these hvo NPT countries in the 1970s to abandon their reprocessing efforts.10 V. Schu.richt and J. Larrimore, ‘‘Safeguarding Nuclear Fuel Cycle Facilities,’ MEA BuZletin, vol. 30, No. 1 (1988), p. 11.

. —Appendix 4-C-Safeguards and the Civilian Nuclear Fuel Cycle I 189niques (see figure 4C-3), including methods for filmprocessing, verification of seals, and analysis ofgamma spectrometric data. New tamper-resistant surveillancetelevision and recording systems have beeninstalled in an increasing number of facilities. llA number of improvements in IAEA safeguards andprocedures have also been adopted since the 1991Persian Gulf War. These include establishing earlierreporting requirements for nuclear plant-design information;taking steps toward more universal reportingof exports, imports, and inventories of nuclear materialsand equipment; reaffirming the right to conductspecial inspections; and accommodating the use ofmore diverse sources of information.Nevertheless, the IAEA safeguards system hasinherent limitations with respect to forestalling potentialnuclear weapon programs, some of which are thefollowing:it does not cover all states, or even all facilitiesand items that could be used by a nuclear weaponprogram in those states that are covered (forexample, it makes no attempt to cover researchand development on nonnuclear components ofnuclear weapons);it does not prohibit states from acquiring stockpilesof weapon-usable material (plutonium andHEU), or the means to produce them, providedthat stocks and facilities are declared and forpeaceful purposes (the IAEA, in fact, is chargedwith assisting member states in the developmentof their nuclear fuel cycles);it suffers from inherent uncertainties at bulkhandlingfacilities;its access to sources of information remainslimited;Two seals, known as COBRA and ARC, used by theIAEA to provide assurance that containers or otherinspected items have not been tampered with betweeninspections.■ it lacks an effective means of enforcement; and■ it is subject to diplomatic and political pressuresto treat all states equally, making it difficult to selectsome as being of particular proliferationconcern or to subject them to closer scrutiny. Thebulk of the IAEA safeguards budget today is spenton facilities in Japan, Germany, and Canada, whichare not regarded as countries of current proliferationconcern.Policy options to strengthen IAEA safeguards andother aspects of the nuclear nonproliferation regimehave been discussed in a number of recent articles 12 andwill also be addressed in a subsequent OTA report onnonproliferation policies.11 o~ti~pment~t~ ~n~proved over~e l~t d~de ~cludm bundle counters forreactor~t aremfuekxi while dhle, ad V~OUSequipment for measuring composition and amounts of nuclear material, for example, portable multichannel analyzers, K-edge densitometers,electromanometers, Cherenkov viewing devices, and neutron coincidence counters.12 S*, for e~ple, ~~ence SCheinrnaq “Nuclear Safeguards and Non-Proliferation in a Changing World Order,” Secun’v DiaIogue,vol. 23, No. 4, 1992, pp. 37-50, and Assuring the Nuclear Non-l%liferafi”on Safeguards System (Washington DC: The Atlantic Council,October 1992); three articles in Disarmament, vol. XV, No. 2, April 1992: Hans Blix, “IAEA Safeguards: New Challenges, ” pp. 33-46;Ryukichi Imai, ‘‘NPT Safegumds Today and Tomorrow, ’ pp. 47-57; and Lawrence Sche@ ‘‘Safeguards: New Threats and NewExpectations, ’ pp. 58-76; and David Fischer, Ben Sanders, Lawrence Scheinrnaq and George BumL A New Nuclear Triad: TheNon-Prol~eration of Nuclear Weapons, International Verification and the IAEA, PPNN Study No. 3 (Southampton U.K.: Programme forPromoting Nuclear Nonproliferatio~ September 1992).

190 | Technologies Underlying Weapons of Mass DestructionFigure 4-C3-Typical Containment and Surveillance (C/S) Measures Applied by the IAEAI/—+!- – - -–-–~“-—+)I Surveillancecameras1-/= .. \\@c--IIII“-—‘-=’’+J=--JJIDoorLorry3IContainerSeal\SOURCE: IAEA %fegumds: An L?trcxiuction, IAWSG/lNF/3 (Vienna: International Atomic Energy Agency, 1981), pp. 24-25,

Appendix 4-DDual-UseExportControlsMeeting in Warsaw from March 31 to April3, 1992, the 27 members of the NuclearSuppliers Group l approved a broad newset of export control guidelines pertainingto the transfer of nuclear dual-use items. They agreedthat each of the NSG member countries wouldimplement the guidelines by the end of 1992 2 andwould adopt a common policy requiring the applicationof full-scope IAEA safeguards as a condition ofarty significant new nuclear exports to nonnuclearweapon states. 3 The new guidelines include a technicalAnnex specifying 65 categories of nuclear-relateddual-use equipment, materials, and technologies thatare to be controlled, and establish procedures governingtheir transfer.GUIDELINES AND LICENSINGPROCEDURESThe new guidelines stipulate the following:1. Licenses shall be required for the transfer of anyitem in the Annex to any destination by anyparticipating country;2. Transfers shall not be authorized:if they are for use in a nonnuclear-weapon statein a nuclear explosive activity (including workon components or subsystems) or in an unsafeguardednuclear fuel-cycle activity;if there is an unacceptable risk of diversion tosuch an activity; orif the transfers are contrary to the objective ofaverting the proliferation of nuclear weapons.3. In judging whether these conditions are met,factors that should be taken into account include,but are not limited to:an evaluation of the appropriateness of theend-use and of the material for that end use;a country’s past compliance history withsafeguards and dual-use tech-transfer obligations;whether governmental actions, statements andpolicies have been supportive of nuclear nonproliferation;and1 The 27 NSG states were: Australi% Austri& Belgium*; Bulgari~ Canada*; Czech and Slovak Federal Republics*; Denmar Iq Firdan@France*; Germany*; Greece; Hungary; Ireland; Italy*; Japan*; Luxembourg; Netherlands*; Norway; Poland*; Portugal; Ro~“ ‘ Russia*;Spa@ Sweden*; Switzerland*; United Kingdom*; and United States.* (Countries with asterisks have been members of the Nuclear SuppliersGroup since it was forrmxi in 1977.)2The guidelines are published in IAEA INFCIRCf254/Rev. I/Part 2, Nuclear Related lkr[-Use Trans$ers, July 1992.3See, for example, Roland Timerbaev, ‘‘A Major Milestone in Controlling Nuclear Exports, ” Eye on Supply, No. 6, spring 1992, pp. 58-65.I 191

192 I Technologies Underlying Weapons of Mass Destruction■ whether the recipient has been involved in thepast in clandestine or illegal procurementactivities.4. Before granting a License, a supplier shall berequired to obtain a statement of end-use andend-use location, as well as a written assurancethat the proposed transfer or any replica thereofwill not be used in any nuclear explosive orunsafeguarded activity.5. Supplier states shall be required to cooperate andconsult with each other on licensing procedures,to report any denials of licenses, and to refrainfrom licensing items whose export was previouslydenied by another supplier state. (Exceptionsand re-evaluations are allowed, however,with appropriate consultation,)In sum, it is presumed that countries withinsufficient nonproliferation credentials-even ifparty to the NPT—will be denied these dual-usegoods.!5ITEMS TO BE CONTROLLED| Industrial EquipmentCombination spin-forming and flow-forming machines■ 2-axis, that can be fitted with numerical controlunitsNumerically controlled machine tools, control units,and software■ especially multi-axis ‘‘contour-control’ machiningdevices■ except that the precision and capability of theseitems must exceed a detailed set of technicalspecificationsHigh-precision (order of 1 micron) dimensional andcontour inspection systems■ especially those capable of linear-angular inspectionof hemishellsVacuum or controlled-environment induction furnaces■ operating above 850 “C;■ except if for semiconductor wafer-processingIsostatic presses■ capable of 700 atmospheres pressure with 6-inchor larger chambersRobotic equipment (grippers and active tooling forends of robot arms)Portion of a remote manipulator that was destroyed inIraq during an IAEA inspection in October 1991. Suchmanipulators can be used inside “hot cells” to handleradioactive material.| able to safely handle high explosives or operate inradioactive environments and capable of variable/Programmable movements■ except if for applications such as automobilepaint-spraying boothsVibration test equipment■ using digital control; 20-2,000 Hz; impartingforces of50kN(11,250 lbs) or moreMelting and casting furnaces-arc remelt, electronbeam, and plasma■ generating temperatures above 1,200 degrees Cin vacuum or controlled environmentsMaterialsAluminum alloys (of specified strength)■ in tubes or solid forms having outside diametersgreater than 75 mm

Appendix 4-D-Dual-Use Export Controls 1193Beryllium metal and alloys■ except beryllium metal windows for x-ray machinesor beryllium oxides specifically designedas substrates for electronic circuitsBismuth (of at least 99.99% purity)Boron or its compounds (isotonically enriched inboron-10)Calcium (high purity)Chlorine trifluorideCrucibles made of materials resistant to liquid actinidemetalsCarbon or glass “fibrous and filamentary” materialsof high-strength■ especially when in the form of tubes with 75-400mm inside diameterHafnium and its compoundsLithium isotonically enriched in lithium-6■ except lithium-6 incorporated in thermoluminescentdosimetersMagnesium (high purity)Maraging steel (of specified strength)■ except forms in which no linear dimensionexceeds 75 mmRadium-226■ except radium contained in medical applicatorsTitanium alloys (of specified strength)■ in tubes or solid forms, with outside diametergreater than 75 mmTungsten and its compounds■ in amounts greater than 20 kg and having hollowcylindrical symmetry with inside diameter between100 mm and 300 mm■ except parts specifically designed for use asweights or garoma-ray collimatorsZirconium and its alloys| except in the form of foil of thickness less than 0.1| Uranium Isotope Separation Equipmentand ComponentsElectrolytic cells for fluorine production (capable of250 g of fluorine per hour)Centrifuge rotor-fabrication andbellows-forming equipmentCentrifugal multiplane balancing machines (with specificcharacteristics)Filament winding machinesFrequency changers (converters) or generators■ with specific characteristics, and operating from600-2,000 Hz■ except if specifically designed for certain types ofmotorsLasers, laser amplifiers, and oscillators■ copper-vapor and argon-ion lasers with 40 Waverage power■ high-pulse-rate lasers (tunable dye lasers, highpowercarbon-dioxide lasers and excimer lasers)■ except continuous-wave or long-pulse-lengthindustrial-strength CO 2lasers for cutting andweldingMass spectrometers and mass spectrometer ion sources, especially when lined with materials resistant toUF 6■ certain exceptions apply, howeverPressure measuring instruments, corrosion-resistantValves (special corrosion-resistant types using aluminumor nickel alloy)Superconducting solenoidal electromagnets■ high magnetic field (greater than 2 tesla)■ with inner diameter greater than 300 mm andhighly-uniform magnetic field■ except if specifically designed for medical nuclearmagnetic resonance (NMR) imaging systemsVacuum pumps (of specified size and capacity)Direct current high-power supplies (100 V, 500 amps;e.g., for EMIS magnets)High-voltage direct-current power supplies (20,000 V,1 amp; e.g., for EMIS ion sources)Electromagnetic isotope separators (EMIS)■ with ion sources capable of 50 mA or more| Heavy-Water Production-Plant-RelatedEquipment (other than trigger list items)Specialized packings for water separationSpecialized pumps for potassium amide/liquid ammoniaWater-hydrogen sulfide exchange tray columns

194 I Technologies Underlying Weapons of Mass DestructionHydrogen-cryogenic distillation columnsAmmonia converters or synthesis reactors| Implosion Systems DevelopmentEquipmentFlash x-ray equipment■ except if designed for electron microscopy or formedical purposesMultistage light-gas guns/high-velocity guns (capableof 2 km,sec velocities)Mechanical rotating mirror cameras (with recordingrates above 225,000 fiarnes/see)Electronic streak and framing cameras and tubes (with50-ns resolution)Specialized instrumentation for hydrodynamic experiments■ velocity interferometers for measuring 1 km/seein under 10 microseconds■ pressure transducers for 100 kilobars| Explosives and Related EquipmentDetonators and multipoint initiation systems■ electrically driven detonators (e.g., explodingbridge wires) capable of nearly simultaneous (2,5microseconds) initiation over an explosive surfacegreater than 5,000 mm 2Electronic components for firing sets● switching devices or triggered spark-gaps (e.g.,gas krytron tubes or vacuum sprytron tubes with2500 V, 100 A, and delays of less than 10microseconds)| capacitors (kilovolt-level, low inductance)Specialized firing sets and equivalent high-currentpulsers (for controlled detonators)High explosives relevant to nuclear weapons (e.g.,HMX, RDX, TATB, HNS, or any explosive withdetonation velocity greater than 8,000 rn/see)| Nuclear Testing Equipment andComponentsFast oscilloscopes (with 1 ns sampling or 1 GHzbandwidth)Photomultiplier tubes (with large photocathodes and1 ns time-scales)Pulse generators (high speed; 0.5 ns rise-times)| OtherNeutron generator systems (for inducing |deuterium nuclear reaction)General nuclear-material and nuclear-reactorequipmentritiumrelated■ remote manipulators (used for radiochemicalseparation in “hot cells”)■ radiation shielding windows (e.g., with leadglass, 100 mm thick)| radiation-hardened TV cameras (able to withstand50,000 grays)Tritium, tritium compounds, and mixtures (containingmore than 40 Ci of tritium)Tritium facilities, or plants and components thereof(including refrigeration units capable of -250 “C)Platinized carbon catalysts (for isotope exchange torecover tritium from heavy water, or to produceheavy water)Helium-3■ except devices containing less than 1 gAlpha-emitting radionuclides or their compounds(having alpha half-lives between 10 days and 200years)■ except devices containing less than 100 mCi ofalpha activitySTRENGTHS OF THE GUIDELINESA wide range of dual-use technologies andmaterials is subject to strict export controls.Implementation of these controls should createsignificant obstacles for a nuclear weapon programattempting to import the specified items.A large number of countries have pledged toabide by these guidelines by adopting them intotheir own export control laws and have agreed notto undermine control actions taken by others.Factors to be taken into account before exportlicenses are granted are not limited to a recipientcountry’s being party to the NPT; these factorsinclude past behavior and general compliancewith nonproliferation goals.

Appendix 4-D–Dual-Use Export Controls | 195POTENTIAL LIMITATIONS OF THEGUIDELINESSpecific technical qualifiers and thresholds applyto the majority of controlled items on the list. Akey questions is how effective each threshold isat determining the equipment’s utility in a lesssophisticatedor less-ambitions nuclear-weaponprogram -could dual-use items falling just shortof the specifications still be helpful, and if so, howeasily could they be obtained from NSG ornon-NSG countries?The procedures only require reporting of licensedenials. This precludes routine active monitoringof trade, for example, to look for suspiciouspatterns of imports. However, the NSG hasagreed to hold annual consultations for purposesincluding discussion on a voluntary basis ofproposed and authorized transfers of these dualuseitems.■ There is no provision for inspecting the end-useapplication, although individual countries maycarry out such inspections on their own. (Inspectionsare periodically carried out, for example, bythe Office of Export Enforcement of the U.S.Commerce Department.) This is primarily due tothe expense and impracticality, both financial andpolitical, of devising a comprehensive inspectionregime for dual-use exports. If the guidelines areapplied stringently, however, then export licensesfor suspect proliferants will largely be denied,reducing the need for end-use inspections.

TheProliferationofIDeliverySystems 5Acountry seeking to acquire weapons of mass destructionwill probably desire some means to deliver them.Delivery vehicles may be based on very simple or verycomplex technologies. Under the appropriate circumstances,for instance, trucks, small boats, civil aircraft, largercargo planes, or ships could be used to deliver or threaten todeliver at least a few weapons to nearby or more distant targets.Any organization that can smuggle large quantities of illegaldrugs could probably also deliver weapons of mass destructionvia similar means, and the source of the delivery might not beknown. Such low technology means might be chosen even ifhigher technology alternatives existed. If the weapons areintended for close-in battlefield use, delivery vehicles withranges well under 100 km may suffice. Strategic targets in someregional conflicts are only a few hundred kilometers from anation’s borders. (A fixed-direction launch system, such as theSupergun being developed in Iraq, might also be used in thesecircumstances.) Deterrence or retaliation against more distantcountries, however, might require delivery ranges of manythousands of kilometers.This chapter focuses on “high end” delivery systems—ballistic missiles, cruise missiles, and combat aircraft-for thefollowing reasons:■ simpler systems, such as cars and trucks, boats, civil aircraft,and artillery systems are not amenable to internationalcontrol. No nonproliferation policy could possibly preventcountries with weapons of mass destruction from utilizingsuch vehicles;, there is a high degree of overlap among the countriespursuing weapons of mass destruction and those possessing,developing or seeking to acquire missiles and highlycapable combat aircraft; andI 197

198 I Technologies Underlying Weapons of Mass Destructionmodem delivery systems enable a country todo more damage to a greater number andvariety of targets, with greater reliability, andpotentially at longer range, than do lowtechnology alternatives. Ballistic and cruisemissiles in particular may have added psychologicaleffects, since they can be harderto defend against, or even to detect, thanmanned aircraft.Combat aircraft are already widely distributedaround the world. Every country currently suspectedof having or seeking weapons of massdestruction also has military aircraft that could beadapted to deliver such weapons. This chapternevertheless examinesthes the proliferation of advancedaircraft for three reasons:■ such a review indicates how and why combataircraft are already so widespread and whatcapabilities they offer;■ states seeking ballistic and cruise missiles doso in the context of widespread aircraftproliferation; and■ since advanced aircraft have proliferatedmore by transfers than by indigenous production,there is the possibility of limitingthe proliferation of still more advancedsystems. 1Even though owners of weapons of massdestruction may possess combat aircraft, there arereasons outlined below why they might prefer touse missiles. Unlike aircraft, however, ballisticand cruise missiles are subject to internationalsupplier controls through the Missile TechnologyControl Regime.This chapter begins with a comparison of theutilities of these three types of system fordelivering weapons of mass destruction. Subsequentsections discuss the technological factorsaffecting the relative ease or difficulty of acquiringeach type of capability, either through purchase,co-development, or indigenous design andproduction. These sections also indicate the typesof observable indicators, or signatures, that ifdetected might reveal attempts to develop, build,or deploy each system.SUMMARY| Effectiveness of Advanced DeliverySystemsAlthough combat aircraft, ballistic missiles,and cruise missiles are not necessary to deliverweapons of mass destruction, each type of vehicleis capable of doing so and each has particularstrengths. A state with the resources, ability, andinclination to acquire delivery systems specificallyfor use with weapons of mass destructionhas to consider the availability of candidatesystems, the type of weapon to be delivered, thetargets to be struck, and the purposes of plannedattacks or threats of attack. Characteristics affectingthe suitability of delivery vehicles to particularmissions include range, payload amount andtype, ability to evade or penetrate defenses,vulnerability to preemptive attack (pre-launchsurvivability), cost, and infrastructure requirements.For delivering a nuclear warhead, the likelihoodof successful delivery somewhere in thevicinity of the target (the combination of prelaunchsurvivability, reliability, and defense penetration)is more important than factors such asaccuracy, cost, or excess payload capacity. Bythis measure, even though missiles are morelikely to penetrate defenses, the reliability ofpiloted aircraft may sometimes count for more.Given their destructive potential, nuclear weaponsneed not be delivered with great accuracy(even a demonstration explosion on the proliferantnation’s own territory or in the ocean couldhave great effect in some situations); neitherwould a nuclear delivery system have to carry1 Competition in advanced weaponry is part of the context in which some countries seek weapons of mass destruction some analysts believethat limiting the spread of advancecl combat aircraft is an important goal whether they would play a direct role in the delivery of weapons ofmass destruction or not.

Chapter 5-The Proliferation of Delivery Systems 1199payloads much beyond the weight of a singlenuclear weapon.To the extent that cost matters in delivering anuclear weapon, it is probably the total cost ofacquiring a delivery capability-not the cost perton of payload—that is relevant. Here, missiles(ballistic or cruise) have a strong advantage, sincethey are generally considerably cheaper thanadvanced aircraft.Aircraft and cruise missiles are better suitedthan ballistic missiles to deliver chemical andbiological agents over an extended area. Size ofpayload matters in chemical and in typicallarge-area biological attacks, since the damagethat can be inflicted depends directly on theamount of agent that can be delivered. 2 In thisrespect, the typically larger payload capacity ofmanned aircraft would give them a strong advantageover both cruise and ballistic missiles.Since known biological and chemical weaponsare cheaper to develop than are nuclear weapons,the cost of their delivery system is a much largerfraction of the total cost, and hence a moreimportant criterion, than in the nuclear case. Toattack military targets with chemical weapons,the cost per ton of delivered payload wouldprobably be important to the attacker. With theirlarger payloads and their reusability, aircraft aretypically cheaper than missiles by this measure.Depending on how biological weapons were used(e.g., once for shock value, or repeatedly forgenocide) either the cost of one sortie or the costper ton of payload could be more important.Aircraft have a strong advantage for attacksagainst military targets, if the targets are mobileor located in unknown positions. Ballistic missiles,on the other hand, would have an advantageif the targets were particularly well defended.| Availability of Delivery SystemsUnlike weapons of mass destruction, whosetrade is heavily constrained by treaties andinternational norms, delivery systems such asaircraft and short range antiship cruise missilesare widely traded internationally. The UnitedStates and other Western industrialized countrieshave tried to delegitimize the sale of longer rangeballistic and cruise missiles by creating theMissile Technology Control Regime (MTCR).When formed in 1987, the MTCR was intended tolimit the risks of nuclear proliferation by controllingtechnology transfers relevant to nuclearweapon delivery other than by manned aircraft.To this end, the MTCR established export guidelinesthat, when adopted by complying nations,would prohibit them from selling ballistic orcruise missiles with ranges over 300 km andpayloads over 500 kg to nonmembers. 3The Persian Gulf War and the recent emergenceof potential secondary suppliers of missileshave helped convince a number of additionalcountries to participate in the MTCR. Beginningwith seven original members in 1987, the MTCRhas grown to 23 full members, with Argentina andHungary now in the process of becoming fullmembers. Another four countries (China, Israel,South Africa, and Russia) have agreed to abide bythe MTCR’s export restrictions (see table 5-l).On January 7, 1993, MTCR member states furthertightened up the export restrictions, agreeing to a“strong presumption to deny’ transfers of 300-km ballistic or cruise missiles regardless of theirpayload, and of any missiles-regardless of range2For attacks on cities, optimally distributed biological agents measuring in the tens of kilograms could theoretically inflict casualtiescomparable to a nuclear weapon. If contagious biological agents were used, damage would be less directly related to amount of agent distributed;however, contagious agents have serious operatioml drawbacks (SW ch. 3). For comparisons of nuclear, chemical, and biological weaponeffects, see ch. 2 of U.S. Congress, Office of Technology Assessment, Proliferation of Weapons of Mass Destruction: Assessing the Risks,OTA-ISC-559 (Washington, DC: U.S. Government Printing OffIce, August 1993).J As appli~ to missiles or unmann~ aerial vehicles, the MTCR prohibits the transfer of complete sysrem.r, components tit co~d ~ usedto make complete systems, and technology im’olved in the production of components or of complete systems. Each participating nation controlsexport of these items through its own national system of export controls, and the controls are coordinated among MTCR members.

200 I Technologies Underlying Weapons of Mass DestructionTable 5-1—MTCR Countries7 original members (1987):Canada, France, Federal Republic of Germany, Italy,Japan, United Kingdom, United States16 additional full members (as of Mar. 25, 1993):Australia, Austria, Belgium, Denmark, Finland, Greece,Iceland, Ireland, Luxembourg, Netherlands, New Zealand,Norway, Portugal, Spain, Sweden, SwitzerlandCountries that have pledged to abide by MTCR provisions,but are not full members:Argentina (pledged May 1991; in process of becoming fullmember, March 1993)China (pledged November 1991)Hungary (in process of becoming full member, March1 993)Israel (agreed October 3, 1991 to abide with MTCRprovisions by the end of 1992; applying for membership,March 1993)Romania (applying for membership, as of March 1993)South Africa (has pledged to join, but date unspecified)Soviet Union/Russia (pledged 1990/June 1991,respectively)SOURCE: Adapted from Australian Department of Foreign Affairs andTrade, press release, Mar. 11, 1993; and Arms Contro/Reporfer, 1993(Cambridge, MA: Institute for Defmse and Disarmament Studies,1993), section 706.or payload—if the seller has reason to believethey would be destined to carry weapons of massdestruction.| Technological Barriers to Delivery-System ProliferationAccording to published sources, ballistic missileswith ranges from 300 to 600 km are alreadypossessed or being developed by over a dozencountries outside of the five declared nuclearpowers. In general, the acquisition by additionalcountries of more advanced missile technologiesthoseallowing ranges in excess of 1,000 km oraccuracies much better than roughly 0.3 per centof range-cm be slowed but not stopped bymultilateral export controlls. It is unlikely that anycountry (other than China and the former Sovietrepublics that already possess intercontinentalballistic missiles) would pose a direct ballisticmissile threat to the United States within the next10 years. However, as the Persian Gulf War andthe ongoing nuclear tensions involving NorthKorea have emphasized, important U.S. allies andoverseas interests can already be put at risk byexisting missiles in a number of countries.Cruise missiles or other unmanned aerial vehiclesthat exceed the MTCR thresholds are notwidespread outside of the United States and theformer Soviet Union, but a number of systemswith ranges of 50 to 200 km are available forpurchase. In addition, technologies for guidance,propulsion, and airframes have recently mademajor advances and are becoming considerablymore accessible to many Third World countries—particularly with the export of more advancedshort range systems and the spread of aircraftproduction technology and co-licensing arrangements.Since very few countries have been able todevelop indigenous aircraft industries capable ofmanufacturing jet engines, it should be possible inprinciple to control the spread of the mostsophisticated engines and propulsion systems.However, the highest performance engines arenot required for simple cruise missiles, andengines with lesser capabilities are becomingincreasingly available on international markets.The availability of satellite navigation services,such as the U.S. Global Positioning System(GPS), the Russian Glonass system, andpossible future commercial equivalents, essentiallyeliminates guidance as a hurdle forweapon delivery by manned or unmannedaircraft. GPS receivers are inexpensive andcommercially available. Although exportable modelsdo not operate at sufficiently high altitudesand speeds to provide much help for guidingballistic missiles (and even custom-made receiversoperating during the entire boost phase wouldhave very limited utility for improving ballisticmissile accuracy), such receivers could be usedwith manned or unmanned aircraft to provideunprecedented navigational accuracy anywherein the world. Even the least accurate form of GPSbroadcasts would be sufficiently accurate foraircraft delivery of weapons of mass destruction.

—Chapter 5-The Proliferation of Delivery Systems | 201| Delivery System Signatures andMonitoringMost long range delivery system programs arehard to hide. Test launches of ballistic missilescan be readily detected, and intermediate and longrange missiles require a lengthy developmentperiod and extensive flight testing at each phase,making an overall program particularly difficultto keep secret. Far from being hidden, civilspace-launch programs-which inherently canprovide knowledge useful to a military program—are usually considered a source of nationalprestige and are proudly advertised. In particular,the two most important aspects of missile capabilityfor weapons of mass destruction-range andpayload-can usually be inferred from monitoringsuch a space-launch program. (Guidancetechnology and accuracy would be more difficultto determine, but are less important for weaponsof mass destruction.) Nevertheless, once deployedon camouflaged mobile launchers, missilescan be exceedingly difficult to track andaccount for.Since combat aircraft are widely accepted asintegral to the military forces of a great number ofcountries, there is no reason to hide their existence.But the act of modifying aircraft to carryweapons of mass destruction, or trainin g pilots todeliver such weapons, might be very difficult todetect without intrusive inspections.Of the three types of delivery system discussedin this chapter, development and testing of cruisemissiles will be the hardest to detect. Severaltypes of civilian-use unmanned aerial vehicles arealso being developed and marketed, and withoutactual inspections it will be very difficult todiscern whether such vehicles have been convertedto have military capability. Monitoringdelivery systems capable of carrying weapons ofmass destruction will have the most success withballistic missiles and highly capable aircraft.EFFECTIVENESS OF DELlVERY SYSTEMSThe delivery capability required to use weaponsof mass destruction varies enormously, dependingon the weapon and the mission. A simple,covert means of delivery, such as smuggling,could be sufficient for a single nuclear or biologicalweapon, whereas a great many aircraft wouldbe required to deliver hundreds of tons ofchemical munitions in a coordinated attack againstdefended sites.The following discussion examines the characteristicsthat affect the ability of combat aircraft,cruise missiles, and ballistic missiles to deliverweapons of mass destruction against relativelyinaccessible targets. 4 These characteristics includerange, payload, accuracy, cost, defensepenetration, and reliability. Although a widevariety of systems have been or could be developedto deliver weapons of mass destruction (seetable 5-2), the delivery systems discussed in thischapter have unique capabilities and thus poseparticular dangers to potential victims. Unlikemines or clandestinely placed bombs, they do notrequire that the attacker be able to gain directaccess to the target, and they can deliver weaponsin far less time than would be required to smugglethem to a target. Unlike artillery shells, rockets, ormortars, they can reach distant military targetsand population centers as well as tactical orbattlefield targets. Unlike torpedoes, they aresuitable for use against land as well as sea targets.Unlike civil vehicles such as commercial aircraftor ships, they have some ability to penetratedefenses.The choice of delivery system will depend onthe political or military circumstances envisionedas well as on the systems’ individual capabilities.In at least one instance of known nuclear proliferation,for instance, delivery-system capabilitiesmay have been all but irrelevant. In a speech to theSouth African parliament in which it was revealedthat South Africa had assembled six nuclearA Much of tie follotig dis~ssion draws on Stanford University, Center for International Security and Arms Control, Assessing BallisticMissile l%f~erarion and Its Control (Stanford, CA: Stanford University, November 1991), pp. 25-56.

202 I Technologies Underlying Weapons of Mass DestructionTable 5-2—Actual and Possible Methods of Delivery— .-Weapon Nuclear Biological Chemical—.Aerial bomb \ v vBomb submunitions v b’jAerial spray tankv 4Ballistic missile, nonseparating reentry vehicle J J JBallistic missile, separating reentry vehicle v’ (poss.) (poss,)Artillery shell /vRocket shell VI ,1 b]Mortar shell b JCruise missile warhead \ (poss ) (poss, )Mine (land) \ $’Mine (sea)Antialrcraft missile warheadTorpedoTransportable cIandestine bomb v) (poss, ) (poss )kVkJJActual casesVTheoretical possibility: (Poss )SOURCE: U.S. Congress, Office of Technology Assessment, Prolieration of Weapons of Mass Destruction: Assessing the Risks, OTA-ISC-559(Washington, DC: U.S. Government Printing Office, August 1993), p. 50.weapons in the 1980s, President F.W. de Klerksaid thatThe strategy was that if the situation in SouthernAfrica were to deteriorate seriously, a confidentialindication of the deterrent capability would begiven to one or more of the major powers, forexample the United States, in an attempt topersuade them to intervene. It was never theintention to use the devices, and from the outsetthe emphasis was on deterrencesPerhaps most importantly, however, choiceof delivery systems will depend on a state’sability to develop or acquire, adapt, andmaintain them. These factors are discussed indetail later in this chapter.| RangeThe importance of a delivery system’s range ishighly specific to the regional context. Seoul,South Korea, for example, is less than 50 km fromthe North Korean border. Major cities and militaryinstallations in Israel, Syria, and Jordan arelocated within a few hundred kilometers of eachother, putting them within reach not only of eachother’s strike aircraft but also short range ballisticmissiles. 6 Distances between key points in otherpairs of Middle Eastern countries are somewhatlarger; Jerusalem, Israel is about 350 km from theclosest point inside Iraq, with Baghdad, Iraq thesame distance from Saudi Arabian territory.Tehran, Iran is at least 525 km from the Iraqiborder, which was one of the principal motiva-SPresident F.W. de Kler~ speech on the Nuclear Nonproliferation Treaty to a joint session of the South African Parliament March 24, 1993,as quoted in Arms Control Today, vol. 23, No. 3, Aprit 1993, p. 28.6 The widely proliferated Scud lmissile, for instance, has a range of 300 km with a payload of about 1,000 kg.

IChapter 5-The Proliferation of Delivery Systems I 203Figure 5-l—Range and Payload of Selected Aircraft and Missiles Operated by Potential Proliferants=Range, payload, and flight-profile4Su-24trade off can vary greatly.8,000 +1’IranIraq7,000 1 A Ballistic missiles + attack aircraftSyriaIMirage F-1+F-4E g y p t ,+Iran F-16Israel +S. Korea - IsraelEgyptPakistanS. KoreaMig-29+IranSyriaEgyptLibyaN. Korea12,000 jPrithvi Scud BMirage-5 Mirage 20001,000 A A .S c u d C ++India IranA IranSyria Egypt Egypt1EgyptN. Korea LibyaIndiao —~1 [ 1 JLibyaPakistan200600 800 1,000 1,200 1,400N. KoreaMaximum range (km)SOURCE: U.S. Congress, Office of Technology Assessment, Proliferation of Weapons of Mass Destruction: Assessing the Risks, OTA-ISC-559(Washington, DC: U.S. Government Printing Office, August 1993), p. 68tions for Iraq to extend the range of its Scud-Bmissiles to about 600 km during the Iran-Iraqwar. 7 Distances between the Korean peninsulaand Japan, and between the nearest major cities inIndia and Pakistan, fall into the 600 to 1,200 kmrange. At ranges of a few thousand kilometers,U.S. allies and out-of-theater powers in Europeand Asia could be targeted from the Middle East,South Asia, or elsewhere.As figure 5-1 shows, most combat aircraft incountries of proliferation concern have ranges farexceeding those of most ballistic and cruisemissiles in those same countries. Moreover, theranges of some aircraft can be extended byin-flight refueling. The need for greater geographicalreach may also motivate the development oracquisition of longer range missiles, or theadaptation of cruise missiles for use from air orsea-based platforms. (The effective reach of suchcruise missiles would be extended by the range oftheir carrier.) A full assessment of the militaryutility of cruise missiles must consider their usein conjunction with aircraft, surface ships, orsubmarines.I Payload Amount and TypeCombat aircraft generally can carry muchgreater payload than can either ballistic or cruisemissiles. Combat aircraft available to proliferantstates typically have payload capacities from7The Iraqi extended-range Scuds were subsequently able to reach cities in Israel and Saudi Arabia during the Persian Gulf War of 1991.

204 I Technologies Underlying Weapons of Mass Destruction2,000 to 4,000 kg, ranging all the way to 10,000kg, whereas missile payloads tend to run from 500to 1,000 kg (see fig. 5-l.). Cruise missiles availableto proliferant nations typically carry muchsmaller warheads than do large ballistic missiles,although there is no reason why larger cruisemissiles could not be developed. Indeed, largecruise missiles are in some ways easier to buildthan smaller ones, albeit also easier to intercept.Without very sophisticated technology, ballisticmissiles are not well suited for deliveringchemical or biological weapons to broad-areatargets. Such targets are most effectively coveredwith an aerosol spray delivered at slow speeds andlow altitudes upwind from the target, a deliveryprofile much better suited to cruise missiles oraircraft. Nevertheless, by the 1960s the UnitedStates had developed submunitions for ballisticmissiles that would spread chemical and biologicalagents more efficiently than would release ata single impact point.For nuclear weapon delivery, both ballistic andcruise missiles have the advantage of not needingto provide an escape route for the pilot. In general,high-flying aircraft are more vulnerable to airdefense than low-flying ones. However, deliveringnuclear weapons with low-flying aircraftrequires either a pilot willing to sacrifice himselfwith his plane, a time-delay fuse, or a lofteddelivery profile in which the bomb is released ona high, arcing trajectory that provides enoughtime for the pilot to fly out of the area.| AccuracyLike range and payload, the accuracy withwhich a weapon of mass destruction must bedelivered depends on the type of weapon and thetarget. Most of the ballistic missiles so fardeployed in countries of proliferation concernhave ranges less than 1,000 km and are unable todeliver weapons with accuracies much better than1,000 meters. In the absence of weapons of massdestruction or large numbers of missiles, ballisticmissiles this inaccurate have little military utility;they are better suited to wage terror campaignsagainst civilian populations or perhaps to badgerlarge military installations.It is not yet clear what accuracies will beachieved by the several countries developing orhaving already deployed missiles of greater than1,000-km range. Depending on the level oftechnology, inaccuracies could range from hundredsof meters to many kilometers. Inaccuraciesat the upper end of this range could be enough tolimit the military effectiveness of even sometypes of weapons of mass destruction (thoughprobably not their political impact).Combat aircraft with sophisticated weapondeliverysystems and well trained pilots, on theother hand, can deliver munitions with accuraciesof 5 to 15 meters, far better than is needed todeliver weapons of mass destruction to wide-areatargets. Cruise missiles that are guided to theirtarget on command from a remote operator canalso attain accuracies much better than crudeballistic missiles. New guidance technologiesmake it possible even for autonomously operatedcruise missiles to attain about 100-meter accuracies.I Costs and Infrastructure RequirementsSince the total expense of producing nuclearmaterials and developing and building a nuclearweapon far exceeds that of any delivery systemdescribed here, it is not likely that cost considerationswill play a very important role in selectionof a nuclear delivery system.Nevertheless, the cost of maintaining a modernair force could affect a state’s ability to deliverlarge-scale chemical attacks, for instance. Atypical estimate for the cost of a single advancedstrike aircraft, including pilot training and severalyears of operations and support, but excluding theinfrastructure investment, is $40 million. (Themarginal cost of a Scud or SS-21 ballistic missile,similarly including operations and support butexcluding launcher and other infrastructure ex-

Chapter 5-The Proliferation of Delivery Systems 205penses, costs only on the order of $1 million. 8 ) Inaddition to their high unit cost, however, advancedstrike aircraft require an extensive supportinfrastructure including maintenance facilities,spare parts, and highly trained personnel.Given that a country has sufficient technicalcapability, it could build and maintain cruisemissiles much more cheaply than piloted aircraft.Cruise missiles need only fly once, and they donot incur the expense of training pilots, nor thestructural requirements of carrying them along,keeping them alive, and ensuring their safe return.Not counting sunk development and productioncosts, each additional U.S. Tomahawk sealaunchedcruise missile costs about $1.5 million. 9U.S. defense engineers estimate that it should bepossible to build an equivalent missile for lessthan $250,000 by substituting low-cost satellitenavigation receivers for the Tomahawk’s sophisticatedradar and optical pattern-recognition guidancesystems. 10In general, however, cost comparisons ofdelivery systems for weapons of mass destructionare likely to be only marginally important. Aproliferant country will probably make do withthe delivery systems it already has or can mosteasily acquire or modify. Prices of deliverysystemacquisition are also difficult to estimate,since they could vary drastically if systems aredumped on world markets by hard-currencystarvedcounties or if effective embargoes areimplemented on sales, so as to drive up prices onthe black market.| Defense PenetrationThe high speed and steep angle at whichballistic missiles strike a target make themconsiderably harder to defend against than eitherpiloted or unpiloted aircraft. The Patriot system,originally designed as an antiaircraft weapon,showed only a limited capability to intercept Scudmissiles during the Persian Gulf War of 1991. 11Furthermore, defending against missile attackwould be considerably harder if missile warheadswere fused to detonate on interception, or if eachwarhead dispersed many submunitions beforecoming into range of the defense.Many developing countries possess air-defensesystems capable of destroying traditional (nonstealthy)strike aircraft that attempt to attackdefended sites. The effectiveness of such defenseswould depend strongly on the sophistication andscale of the attack. Evidence from recent airengagements indicates that properly equippedand maintained strike aircraft-operated in conjunctionwith defense-suppression techniques (e.g.,electronic countermeasures and attacks on airdefense batteries)-can penetrate sophisticateddefenses with losses of at most a few percent overthe course of a campaign. 12 Although many ThirdWorld air forces would not be able to mount sucha sophisticated and sustained air campaign, thosepursuing weapons of mass destruction, with fewexceptions, each have relatively advanced combataircraft that might be used with sufficienteffectiveness even against defended areas.Whether an extensive air campaign would benecessary would depend on the context. A singlenuclear weapon can destroy a city, and a relativelyg Stanford, Assessing Ballistic Missile Proliferation, op. cit., footnote 4, p. 45.9Steve Fetter, ‘‘Ballistic Missiles and Weapons of Mass Destruction: What is the Threat? What Should be Done?” lnternarionul Securify,vol. 16, No, 1, Summer 1991, p. 11.10 As cited in ibid.11 Althoughewly claims of Patriot success rates were clearly too Optimistic, the system’s Overall WrfO~ ce against Scud attacks may neverbe known exactly. See, for example, Theodore A. Postol, “IMsons of the Gulf War Experience with Patrio~” International Securify, vol. 16,No. 3, Winter 1991N2, pp. 161-171; and Robert M. Stein and Theodore A. Postol, “Correspondence: Patriot Experience in the Gulf War, ”lnfernarional Security, vol. 17, No. 1, Summer 1992, pp. 199-240.12 See, for e~ple, JOhKI R. ~ey> “Regional Ballistic Missiles and Advanced Strike Aircraf~” International Securify, vol. 17, No. 2,Fall 1992, p. 59.

206 I Technologies Underlying Weapons of Mass Destructionsmall amount of properly delivered biologicalagent could kill tens of thousands of people.Therefore, if a state is willing to tolerate higherlosses of airplanes, pilots, and weapons—and if itis able to persuade its pilots to fly in spite of thoserisks-it may well be able to deliver weapons ofmass destruction by air even against welldefendedsites. Of course, this option was apparentlynot available to Iraq in the 1991 Persian GulfWar, since its air force was so mismatched withthat of the coalition forces that its leaders decidednot even to mount a serious aerial counterattack.Cruise missiles can be effective at attackingdefended targets, relying on their ability toexecute low-altitude, circuitous approaches. Theymay also be air-launched and accompanied byaircraft in a defense-suppression role, makingeven short range cruise missiles particularlysuited to attacking defended targets. Even ifcruise missiles were detected, they can fly ataltitudes below the reach of many medium or longrange surface-to-air missiles, leaving only antiaircraftartillery or short range surface-to-air missilesto shoot them down,| Reliability and SurvivabilitySince they are single-shot systems, ballisticand cruise missiles are generally less reliable thanmanned aircraft, which are designed with pilotsafety and multiple sorties in mind. 13 The types ofredundant systems used to provide safety onaircraft are harder to provide for ballistic or cruisemissiles, since a missile’s range is more sensitiveto changes in payload. Moreover, aircraft aregenerally tested in the design process morethoroughly than ballistic or cruise missiles, andmore mission-critical systems in an airplane canbe tested prior to use than in a ballistic missile.(For example, a solid rocket motor cannot betested without being used up, and most liquidfueledmotors are only designed for a singlefining.) Aircraft also tend! to fail gracefully andcan usually return to base if problems areencountered.Nevertheless, a state with a nuclear arsenal ofonly a few very expensive weapons may well paythe price-in cost and performance-of makingits missiles more reliable. (This would likelyinvolve a substantial engineering effort, precludinguse of an “off-the-shelf’ missile designed toless demanding requirements.) But even a reliablemissile would likely be less forgiving of failurewhen it did happen than would an airplane. In theevent an airplane fails to take off successfully, itsweapon and its mission can usually be recovered—an important consideration in the case of a nuclearweapon whose completion may have cost a statea noticeable fraction of its gross national productfor many years. Warheads are less likely tosurvive launch failures when mounted on cruiseor ballistic missiles.The pre-launch survivability of ballistic andcruise missiles is likely to be higher than that ofairplanes, however, since they are smaller, canmore readily be hidden, and do not need to belocated near runways or landing strips. DuringOperation Desert Storm the coalition air forcespinned down or destroyed much of the Iraqi airforce, but they may not have actually destroyed asingle Scud missile or mobile launcher. Oncelocated, however, missiles are more vulnerablethan aircraft, which can flee or protect themselves.| Command and ControlPolitical leaders may find missiles (certainlyballistic missiles, but perhaps cruise missiles aswell) to be more ‘‘controllable” than pilotedaircraft in that the infrastructure required tolaunch missiles is significantly smaller than thatneeded to sustain air operations. Launch ordersneed pass through fewer levels of command, andfewer people are in a position to block them.Perhaps most fundamentally, an unpiloted missile13 Reliabfi~ hen is defined as Ihe probability of successful flight given that pre-flight or pre-launch ch=b hve ken pmsd.

Chapter 5-The Proliferation of Delivery Systems I 207cannot question its launch order. Groundlaunchedcruise missiles could have infrastructuresmore the size of those for ballistic missilesthan those for piloted aircraft. Although deployingair- or sea-launched cruise missiles wouldrequire the participation of an air force or navy,with its attendant logistical and command structures,the launching platform could remain out ofrange of enemy forces. Thus, its logistical infrastructuremight still be considerably less than thatrequired to penetrate enemy airspace usingmanned aircraft.| Achieving Tactical SurpriseIntercontinental ballistic missiles (ICBMs) canreach targets a quarter of the way around the globein about 30 minutes. Tactical missiles completetheir flight in even less time. Even thoughmissiles traveling over ranges of a few hundredkilometers can be detected by early-warningradars or space-based infrared sensors early intheir flight, they travel so fast that there is stillvery little warning of their arrival. Iraqi Scudstook about seven minutes to reach Israel, travelingat up to eight times the speed of sound, andthe Israelis had about five minutes’ warning oftheir arrival. 14 Combat aircraft could cover thesame distance in about a half-hour. However,when hugging the ground over routes that masktheir approach, they could hide from search radarsand arrive on target with about as little warning asballistic missiles. 15 Cruise missiles in general areharder to detect than aircraft because they aresmaller, quieter, and operate at lower skin andengine temperatures. However, to take as muchadvantage from terrain masking as some aircraftcan, they would require advanced guidance systemsand accurate geographical information forplanning flight routes.| Target AcquisitionIn the absence of remote, near-real-time reconnaissancecapabilities, which are beyond thecapabilities of most states, neither ballistic norcruise missiles are suitable for use against mobiletargets. Piloted aircraft would be the only availablechoice for such missions-and even then,only for some of them. As noted above, forexample, even a determined coalition aircampaignhad great difficulty locating and attackingIraqi Scud launchers. Delivering chemical orbiological weapons against moving military formationswould call for pilot judgment, as mighttactical uses of nuclear weapons. Attacking citiesor fixed military bases with any of these weapons,however, would not demand precise targetacquisitioncapabilities.Piloted aircraft have a clear advantage formilitary missions in which it is important toascertain quickly that the weapon has beendelivered to a target and detonated. Ballisticmissiles do not provide any such indication, nordo autonomously guided cruise missiles. A cruisemissile that was guided to its target via data linkto a remote operator could send information (e.g.,video imagery) indicating whether or not itarrived at its intended target. But this informationwould not necessarily indicate whether the warheaddetonated, much less whether the target wasdestroyed. 16BALLISTIC MISSILES| Classification of MissilesA “ballistic missile” is a rocket-powereddelivery vehicle that has some form of guidancesystem, that is primarily intended for use againstground targets, and that travels a large portion ofits flight in a ballistic (free-fall) trajectory.Ballistic missile flight profiles are usually de-14 Postol, “LESSom of tie Gulf War Experience with Pahioq ” op. cit., footnote 11, pp. 161-171.15 S[mford, Assessing Ballistic Missile Proliferation, op. Cit., fOOtnOte 4, p. 43.16 Airc~[ pilots, too, c~hve difficu]tyrnaking accurate bomb damage assessments. Despite its sophisticated reconnaissmce systems, U.S.bomb damage assessments during the Persian Gulf War were still incomplete and delayed.

Table 5-3-Space-Launch Vehicles and Ballistic Missiles With Ranges Over 100 km in Non-MTCR CountriesProducing Missile Range Payload Accuracy Fuel/ importedcountry a designation Status b [km] [kg] CEP [m] stages Comment c missiies dCountries with indigenous missile programs:ii—FormerSoviet Union dSS-21 (Scarab)Scud-B (SS-1)ss1203004501,000240-300500-900solid/1liquid/11976 IOC1962 IocChina dM-1 1M-9DF-3A (CSS-2)s?Ds6002,500-3,000 2,000300?”300-6002,500solid/2solid/lIiquicVl1990 Ioc?—1971 IocIsrael Jericho 1Jericho iiJericho IIBShavitssTs480-6501,5002,5002,500/7,500250-500650-I,000?700?750/150smali???NAsolid/2?solid/2solid/2solid/3w/France; 1973 IOCw/France; 1990 IOC—SLV; w/France; 1988 IOCLance foIndiaPrithviAgni"ICBM”SLV-3ASLVPSLVGSLVTTPsTTP150/2502,5005,0004,0008,00014,0001 ,ooo/5oo1,000?100150-500?1,0002,500250?2,500?Smaii?NANANANAliquidsolid-liq/2NAsolid/4?solid/4liq-solid/4cryo/solid1992 IOC?w/France, FRG; 1989 test—SLV; 1980 IOCSLV; w/France, FRGSLVSLVTaiwanChing Fenghen Maname unknowns-?D-?D?100-130950[950]?275-400?500????NAliquid/1solidsolid?/3?like Lance; w/lsrael; 1983 IOC“Sky Horse”; canceled?SLVNorth Korea(DPRK)Scud-BScud-CNodong-1ss?T?3406001,0001,000500-7001 ,Ooo?=1 ,~(j‘??liquid/1liquid/1liquid/1 ?w/USSR, Egypt?w/Chinaw/ChinaFROG-P;Scud-B (via Egypt)South KoreaNHK-1Korean SSMname unknowns-?TD-180260[4,000]??NAsolidsolid/2w/U. S.; 1978 IOC.SLV; development began1987(Continued on next page)

Table 5-3-Space-Launch Vehicles and Ballistic Missiles With Ranges Over 100 km in Non-MTCR Countries—(Continued)Producing Missile Range Payload Accuracy Fuel/ Importedcountry. designation Status b [km] [kg] CEP [m] stages CommenF mlssiles dBrazilOrbita MB/EEAvibras SS-300MB/EE-350(MB/EE)?-600MB/EE-1000SS-loooIRBMSonda 3Sonda 4VLS (Avibras)D?T-D.?D-?D-7D-?P?sS?D?1503003506001,0001,2003,00080950[10,000]5001,000500500???135160-500?solid/1liquid/1solidsolidsolidsolidsolidsolidsolidsolid?/41991 IOC?suspended; 1991 IOC?;MB/EE’s in abeyance——SS-series in abeyance—SR; w/FRGSR; w/FRG, FranceSLV; w/FRGArgentinaAlacranCondor IIDD-200900100-500?Solid/1solid/2consortium; 1989 testcanceled 1991; SLV plans?South AfricaArnistonRSA-4TD500-1,500[10,000]500-1,000? ?NAsolidsolid/3w/lsrael (Jericho 11?); ’89test SLV; test planned 1996Iraq(beforeGulf War)Fahd 300/600A1-HusaynA1-Hijarah/AbbasTammuz-1(A1-Abid)Dss?D300/600600750-9002,000? ?150-500? 3,0001 00-300? 3,000750? ?solid/1liquid/1liquid/1liquid/3?— FROG-7; Scud-Bmodified Scud-B; 1988 IOCmodified Scud-B; 1990 IOC?SLV?; w/USSR; December1989test;clustered booster?0IranMushak-120Mushak-200Scud-B“Iran-700”Tondar-68sDS?D?D1202003007001,000500 ?500? ?1,000 1,000? 600?400? ?solid/1solid/1liquid?/1?solidw/China; 1990 IOC?w/Chinaw/DPRK; 1984 IOC?—w/ChinaScud-B&C (from DPRK);M-9 (negotiations);Nodong-1 (negotiations)(Continued on next page)

Table 5-3-Space-Launch Vehicles and Ballistic Missiles With Ranges Over 100 km in Non-MTCR Countries-(Continued)Producing Missile Range Payload Accuracy Fuel/country a designation Status b [km] [kg] CEP [m] stages Comment c Imported missiles dNoPakistan Hatf II T 300Hatf Ill D? 600Suparco s [300]name unknown P [1 ,200]500500-1,000????NANAsolici/2?solid/1 ?soiid/2?soiid/3?w/France, China; 1988 testw/China; staiied?SR; w/France; China?SLVM-1 1 (under negotiation)Egypt Scud-B D7 300Scud-100DVector (Badr- D-?

Chapter 5–The Proliferation of Delivery Systems 1211scribed in terms of three phases: the boost phase,in which the propulsion system generates thrust;the midcourse phase, in which the missile coastsin an arc under the influence of gravity; and theterminal phase, in which the missile experiencesstrong decelerating forces during its descent intothe atmosphere. Missiles with ranges under 300km remain in the atmosphere for their entiretrajectory (and travel slower than longer rangemissiles), thus reducing the abruptness of thereentry transition. 17 In this chapter, all rangesrefer ‘minimum-energy trajectories, ’ which maximizethe range available to a given missile. 18Although unguided rockets, such as the SovietFROG-5, the U.S. Honest John, and the IranianOghab rockets, maybe useful in some battlefieldsituations, they will not be considered here,primarily because their ranges are generally muchless than 100 km even with small payloads.Similarly, rocket-assisted artillery, surface-to-air,air-to-air, and air-to-surface missiles are notincluded in this analysis.A functional ballistic missile must (i) employa propulsion system to provide thrust (ii) have aguidance and control system to direct its thrust(iii) carry a useful payload, and (iv) be supportedby some sort of launcher, e.g., a freed gantry, amobile truck-mounted erector-launcher, or a silo.The missile and its payload must be designed towithstand the mechanical and thermal stressesinvolved in launch and final approach to a target.For missiles with ranges substantially greaterthan about 400 km, the final approach involvesreentering the atmosphere from space at very highspeeds, causing intense heating, deceleration, andthe possibility of strong lateral forces. Thedifficulty of designing missiles for a givenpayload therefore increases dramatically withrange and level of accuracy.Missiles are characterized in terms of severalkey parameters. The most fundamental of theseare the missile’s range and payload, Payload isdefined as the mass of the warhead(s) or otheruseful material (not counting the empty boostercanister, for instance) that the missile can deliverat a given range. Within certain limits, payloadcan be traded off against range. (The same is truefor aircraft and cruise missiles.) Accuracy refersto the likelihood that the payload will be deliveredto within a certain distance of an intended target.There are both systematic and random contributionsto inaccuracy, but in many cases the randomerrors are more important. Random errors arequantified by the Circular Error Probable (CEP),which defines the radius of a circle on the groundinto which half of a large number of identicalmissiles launched along the same intended trajectorywould fall. 19 Missiles are also characterizedin terms of their number of propulsion stages, orsequentially firing boosters.I Status of Missile ProliferationTable 5-3 illustrates the existing or developingmissile programs in countries that were not fullmembers of the MTCR as of March 1993, asreported in public sources. (For China and theformer Soviet Union, only missiles known orsuspected to have been exported to other countriesare included.) Since the sources for thistable contain substantial variance and uncer-1’7 me limit of the tangible atmosphere OCCUrS at approximately 100 km altitude (below which the lighter and heavier airmokdes ae neaflyuniformly mixed). At 100 km altitude, air density and pressure are roughly one millionth of their values at the Earth’s surface.18 Shofierrages ~esu]t when ~ssilc~ me launched at angles ei~er closer to tie horizon~ Or closer to tie vticd than the Illklklllm-energylaunch angle. Such trajectories are called ‘‘depressed’ or “lofted.”19 CEP does not tie into account either launch failures or the systematic errors associated with mis-aiming tie missile in tie fist PIWX,called the ‘‘bias. ’ The CEP is also a median, rather than a mm it does not predict how@ outside the circle the other half of the missileswill land. (For instance, some of Iraqi Scuds fired toward Israel during the Persian Gulf War landed quite far from intended targets or in theMediterranean Sea.) Furthermore, in practice the expected miss-distance is usually elongated in the downrange directio~ leading to an ellipticalrather than circular error pattern. Therefore, even ignoring the bias, the CEP gives only a rough indication of the likelihood that a missile willhit an intended target.

212 I Technologies Underlying Weapons of Mass DestructionTable 5-4-Ballistic Missile Production CapabilitiesCategory Description CountriesAdvanced Able to design and produce missiles India Israei, and possibly Taiwancomparable to those produced in theUnited States in the mid-1960s (e.g.,ICBM-range ballistic missiles and spacelaunchvehicles) nIntermediate Able to reverse-engineer, introduce Brazil, North Korea South Korea,changes to, and manufacture Scud-ilke and possibly Argentina and Southmissiles, and to make solid-propellant Africashort-range missilesIncipient some capability to modify existing Scuds, Egypt, Iran, Iraq (before the Perbutlittle elsesian Gulf War), and PakistanNo indigenous No missile design or manufacturing capa- Afghanistan, Libya, Saudi Arabia,capability bility, but have imported missiles with Syria, Yemen, and possibly Algerangesabove 100 kmria and Cubaa ~mpara~e ca@uHy, however, refers primarily to the design and assembly capability of large soiid-pmpellantmotors, and does not imply U.S. levels of manufacturing capadty.SOURCE: Stanford Llniversity, Center for International Security and Arms Control, Assessing Ba//istic Missi/eProliferation and /ts C:ontro/(Stanford, CA: Stanford University, November 1991), p. 153.tainties in reporting the status or specificationsof some missile programs, a range of estimatesis indicated where appropriate.Table 5-3 shows that 13 non-MTCR countries(not counting China and the former Soviet Union)may have indigenous missile-development programsfor ballistic missiles exceeding 100 km inrange. Only two of these, however—Israel andIndia-have demonstrated capability sufficientfor indigenous design and production of multistagemissiles. 20 Another six countries haveimported missiles but have virtually no capabilityto develop or manufacture them. Most of theimported missiles have come from the formerSoviet Union-Scud-Bs, FROG-7s, and someSS-21s—and many of them were obtained morethan a decade ago. More recently, however, Chinahas exported 2,500-km range DF-3s and possiblyM-9s and M-lls, and North Korea has exportedScud-Cs. According to one analysis, the 19countries mentioned above fall roughly into fourcategories, which are described in table 5-4. 21Indigenous capability is only one factor affectingmissile proliferation. In the past, countrieshave been able to enhance their missile capabilitiessubstantially from what they could have doneXI Wwm ~50 hm relatively ad~~ced aerosp~e industrial capability, but its ballistic-missile and space-launch pro- (other ~ workon satellite vehicles themselves) have largely been on hold for many years.21 ~ew ~tegorifiom, as we[l as the framework for evaluating indigenous capability, were developed in the Stanford report, AssessingBallistic Missile Proliferation, op. cit., footnote4, p. 153. Study methodology for that report included preparing detailed proffles for 17 subjectproliferant countries that surveyed national, geographical, economic, and regime parameters, current conflicts and recent history, militaryposture, and the record of ballistic: missile acquisition. See Ballistic Missile Proli$erarion Study Country Profiles, Center for InternationalSecurity and Arms Control (CISAC), Stanford University, July 1990 (unpublished). The study participants also examined technical featuresof missiles deployed or under development in the subject countries, along with key technologies needed for indigenous production. Many ofthe study participants have close ties to missile and aircraft development and production in both private industry and government. Principalauthors (affiliated with CISAC unless indicated otherwise) were John Barker (Graham& James), Michael Ellernan (CISAC and Lockheed),John Harvey, and Uzi Rubin. Other study participants were: Ronald Beaver, David Bernste@ Hua Di, Phil Farley, IAwis Franklin (CISACand TRW, Inc.), Susan Lindheim, Michael McFaul, and William Perry.

Chapter 5-The Proliferation of Delivery Systems | 213on their own by importing missiles or advancedcomponents, or by participating in joint ventures(e.g., between Argentina, Egypt, and Iraq todevelop the Condor II missile). However, sincethe MTCR has restricted many of the outsidesources of cooperation and assistance on missiledevelopment, indigenous capability has becomemore important for most countries of proliferationconcern.To understand the problem of missile proliferationmore fully, trends in these capabilities mustalso be taken into account. According to at leasttwo estimates, most of the countries in the topthree categories of capability could advance upwardin the list by about one category during thenext decade, placing Israel, India, Taiwan, SouthKorea, Brazil, and possibly North Korea andSouth Africa in the “Advanced” category, andPakistan, Iran, Argentina, and Egypt in the “Intermediate”category. 22 Assuming continuation ofconstraints imposed by U.N. Resolution 687 onIraq’s weapon programs, Iraq would be the onlycountry remaining in the ‘‘Incipient’ category.If countries are willing to dedicate sufficientresources to their missile programs, most ofthese advances in capability could occur evenunder a well-functioning MTCR. MTCR constraints,however, can significantly increasedevelopment costs, helping to convince leadersthat the benefits are not worth the expense. Theballistic-missile programs in Brazil and SouthAfrica for instance, may well not advance significantly,in part because of increased costs. (Brazil’sdiminishing export market and the decline in thethreat that South Africa perceives itself to facemay also be playing a large role.) Furthermore,largely because of diplomatic efforts by theUnited States since the 1970s, Taiwan and SouthKorea do not appear to be aggressively pursuingeither ballistic-missile or space-launch programsat the present time, although they would have thetechnological capability to do so if they chose.Even if such advances did take place, a largegap would remain between the capabilities ofmost of these nations and what would be neededto strike the United States. According to then-CIADirector Robert Gates, “Only China and theCommonwealth of Independent States have themissile capability to reach U.S. territory directly.We do not expect increased risk to U.S. territoryfrom the special weapons of other countries-ina conventional military sense-for at least anotherdecade. . . .’ ’ 23 Among the handful of countrieswith both the technological capability andthe resources to develop long range ballisticmissiles over the next decade, few if any wouldlikely have the intent to target the United States.| Missile Propulsion TechnologiesThe engineering fundamentals of rocket propulsionsystems are well documented in standardtexts. 24 In theory, there are few secrets involvedin basic missile design. In practice, however,considerable expertise is required to integrate thevarious aspects of a ballistic missile into amilitarily useful device.Two kinds of chemical propulsion technologies—solidand liquid fuel-are widely used inballistic missiles. Both rely on b urning a fuel athigh temperatures and expelling the hot combustiongases out the back of the engine. Whereasaircraft and many cruise missiles use oxygen inthe atmosphere to burn the fuel they carry,ballistic missiles are unable to do so and must22 s~ord, Assessing Ballistic Missile Prol.iferution, op. cit., footnote 4, p. 154; and Ballistic Missile Proliferation: An Emerging Threat(Arlington, VA: System Planning Corp., 1992) p. 28, Some reports indicate that Iran may have already moved into the “intermediate” categorywith indigenous production or assembly of Scud-B missiles. See, for example, Joseph S. Bermudez, Jr., ‘ ‘Ballistic Missiles in the ThirdWorld—Iran’s Medium Range Missiles, ’ Jane’s Intelligence Review, April 1992, pp. 147-152.23 ~s~ony of then CIA dirmtor Robert Gates, before the Senate Committee on Governmental Affairs, Jm. 15, 1992, P. 3.~ See, for ex~ple, Gmrge P. Sutton and Donald M. Ross, Rocket Propulsion Elements: An Introduction to the Engineering CIf Rockets,6th edition (New York: John Wiley and Sons, 1992).

214 I Technologies Underlying Weapons of Mass Destructioncarry their own oxidizer. 25 In liquid-fueled boosters,the oxidizer is usually kept separate fromthefuel and mixed with it only in the final combustionchamber. In solid ‘boosters, the oxidizer iscontained in the propellant mixture. Regardless ofthe fuel type, however, ballistic missiles generallyreach much higher speeds than other kinds ofdelivery vehicles with comparable payloads. Even100-km range missiles, which remain in theatmosphere, typically strike their targets at approximatelythe speed of sound (330 rn/see, or740 mph), and 1,000-km missile warheads areonly slowed by the atmosphere from 3 km/see toabout 1 km/sec (2,200 mph). 26LIQUID-FUELED PROPULSIONA country that operates chemical processingfacilities would likely also be able to manufacturefuel and at least crude components for short rangeliquid-fueled missiles such as Scuds. Althoughmany liquid fuels are physically hazardous due totheir corrosive, explosive, carcinogenic, and toxicproperties, several types are already in use byabout a dozen developing countries. 27Liquid-fueled engines more powerful thanthose found in Scuds, however, are correspondinglyharder to build (figure 5-2 shows a schematicdiagram of a liquid-fueled engine). Substantiallygreater experience is required in thedesign and manufacture of their components,including precision valves, injectors, pumps,turbines, and combustion chambers-many ofwhich would call for numerically controlledmachine tools or highly skilled machinists tofabricate. The added difficulties include: thedesign and fabrication of larger components withFigure 5-2-Schematic Diagram of aLiquid-Propellant Rocket EngineTank pressurizationvalve(nfiFuelOxidizertanktankIYOxidizerpumpq-y, Turbine, v.J ives \‘7!generator ~K-\--- c~>d~— Heat— >-/exchangerLJ/Thrust ‘JJ Exhaustchamberduct -—I IiiExhaustnozzleSOURCE: George P. Sutton and Donald M. Roes, F&#@ Prupu/sionElements, 5th edition (New York, NY: John Wiley and Sons, 1986).Copyright @ 1986 by John Wiiey & Sons, Inc. Reprinted by permissionof John Wiley & Sons, Inc.t~ Bwistic ~si.les carry their own oxidizers both to help reach the speeds needed for long range ballistic trajectories and because oxygenbecomes too scarce at high altitudes. Propulsion systems that scoop up external air (called “air breathers’ ’)-except for more sophisticatedtechnologies, such as high-speed mmjets and scramjekare much more limited in the speeds they can achieve. Note, however, that short rangeair-launched cruise missiles, for example, can also be rocket-powered and can be designed to achieve supersonic speeds as well.26 See Jumgen AI- SDIforEUrOpe.7 Techm”calAspects ofAnti-Tactical Ballistic Missile Defenses, Peace Research Institute Fr_Research Report 3/1988, Septem&x 1988, pp. 27-28.z? co~o~y used fuels include hydmzine and unsymmetrical dimethyl hydraz.ine (UDMH), which are burned using the oxidizers nitrogentetroxide or inhibited red fuming nitric acid (IRFNA). Scuds, for instance, use UDMH and IRFNA. Readily available liquid fuels that can alsobe used in rockets include gasoline, kerosene, ethyl alcohol, and liquid ammonia.

Chapter 5–The Proliferation of Delivery Systems I 215Figure 5-3—Schematic Diagram of a Solid-Propellant Rocket Engine(“Motor caseNozzleIv /$Ignder > Center borePropellant grainF~~/\Stress rellef grooveFlex jointSOURCE: Center for International Security and Arms Control, Stanford University, Assessing Ba//istic A.4issi/eProliferation andks Corrfro/(Stanford, CA: Stanford University, November 1991), p. 136. Reprinted by permission ofStanford University.tighter tolerances; greater cooling requirementsfor engine parts exposed to high-temperaturecombustion gases; and more rigorous requirementsfor combustion stability, in order to avoiddangerous flow oscillations during thrust.Moreover, to avoid gross inaccuracies, liquidfueledengines capable of delivering sufficientthrust to deliver a 500 kg payload more than 1,000to 1,500 km must employ a much more complexsystem of valves, pressurizers, flow-control meters,and actuators than are needed for lesspowerful engines, to control and terminate thethrust precisely. If lesser quality components aresubstituted, for example, from (dual-use) chemicalmanufacturingor petrochemical-industry equipment,their poor performance might require developmentof a post-boost vehicle—a final stagecapable of course corrections-to achieve evenmodest (several-kilometer) accuracies. 28 This wouldpresent an entirely new set of design problems.In order to design these larger engines, manywell-trained and experienced combustion scientists,chemical engineers, heat transfer specialists,and experts in fluid mechanics and mechanicaldesign would be required, along with a wellfunded,multiyear research and development program.Because of the similarity between someaircraft and missile components and the types ofmachining required to produce or maintain them,experience with aircraft maintenance facilitiesand especially with production, assembly, andrebuilding of jet engines might be very helpful inthis regard. 29SOLID-FUELED PROPULSIONAlthough conceptually simpler than liquidfueledmissiles and involving almost no movingparts, solid-fueled missiles require years of practicalexperience to design and develop successfully,to learn how to manufacture safely, and tomake accurate (figure 5-3 shows a schematicdiagram of a solid-fueled booster). In addition tothe advantage many proliferant countries have byalready possessing liquid-fueled Scuds or theirvariants, the technology behind liquid-fueledengines can more easily be ‘‘reverse engineered’than can solid-fueled boosters. Taking apart‘2S For Cxmple, a valve that shut off 0.25 seconds too late at bum-out (when a 1,000-km range mksile might be accelera~g at 100 ~sm2)would lead to a vcloeity error of 25 m/see and about a 17-km overshoot at the target. (Range is roughly proportional to the bum-out velocitysquared, and bum-out velocity is about 3 Ian/see at 1,00@krn range.)29 Stanford, AsXe.T.Ting Ballistic Missile Proliferation, op. Cit., footnote 4, p. 135.

216 I Technologies Underlying Weapons of Mass Destructionsomeone else’s solid missiles reveals little aboutthe processes by which they were put together.The performance of liquid engines can be studiedin detail by refueling and retesting them on statictest stands, including partial throttle or earlytermination of thrust if problems develop duringa test. The performance of solid motors, on theother hand, is heavily dependent on the way thesolid fuel is cast into the particular missile, andonce fired, it is almost impossible to stop theburning fuel in the middle of the test. If a solidmotor fails on the test stand, there may be norecoverable data from which to try and correct theproblem, and it might not even be clear if theproblem was generic to the design or specific tothe missile being tested. Even replicating thefailure mode of such a test can be exceedinglydifficult. 30 When launched, solid-fueled motorsalso require sophisticated thrust-termination mechanismsor computer-controlled maneuvers to useup excess propellant while remaining fixed on agiven target; their burning fuel cannot be shut offsimply by closing a valve. 31Since solid-fueled motors can be transportedand stored with the propellant intact, and readiedfor launch much more quickly than their liquidfueledcounterparts, they offer operational andtactical advantages over liquid-fueled missiles.Many solid propellants from the 1950s and 1960sare well understood both theoretically and practically,and enough has been published about themto make this information easily available. Oncethe practical aspects of manufacturing solidfueledmissiles are mastered, far fewer componentsneed be assembled, and production isconsequently more straightforward. Hence, abouta half dozen countries appear to be focusing theirmissile development programs primarily on solidfueledtechnology.Indigenous manufacture of steel motor cases,while requiring well-trained metallurgists and amoderately sophisticated steel treatment facilityfor rolling, forming, and welding chambers,would not present much difficulty for countrieswith metallurgical experience from manufacturingships, oil pipelines, or oil-drilling equipment.32 Very large chambers for intermediate-orlong range missiles would require more sophisticatedmetal-working capabilities than typicallyfound in these industries, however, because of thehigh temperatures and pressures they would haveto withstand. 33The most challenging aspect of manufacturingsolid-propellant motors involves safely preparing,ing, and casting the entire propellant—called the “grain”—into the missile case. Forsmall motors and short range missiles, this isrelatively simple. But as the motor size increases,preparing and casting a uniformly structured,well-bonded propellant grain can become problematic.Preparing the mixture itself is not significantlyharder than other chemical processes involvingexplosives. The oxidizer crystals must be groundto the proper size in a controlled environment andthen carefully analyzed for impurities that couldupset subsequent manufacturing steps or burningcharacteristics. The propellant ingredients consistof relatively dense solid particles suspended in amuch-less dense liquid plastic material called a“matrix.” To improve their structural, manufacturing,and burning properties, solid-propellantgrains employ mixtures of crystalline oxidizersand powdered metal fuel in a plastic matrix that~ C. Robert DieW, senior missile designer (retired), LQckheed Missiles and Space CO., private ~mmUniUtiOq Dec. 8, 1W2.31 me fonvard thrust of solid-fueled boosters can be cutoff by blowhg out thrust-tti tionports at the top of the booster, but this techniqueis relatively sensitive to error. Some missiles, such as the Indian Agni missile and certain space-launch vehicles, employ a combination of solidand liquid boosters to exploit the relative advantages of each.32 Stiord, Assessing Ballisti,z Missile Proliferation, op. Cit., footnote 4, p. 135.33 Some motor ~ses me fa~

... .Chapter 5-The Proliferation of Delivery Systems | 217usually contains precise amounts of curing agents,catalysts, plasticizers, burn-rate modifiers, andprocessing aids. These ingredients must be combinedin a specially designed large batch mixer toachieve uniformity of the propellant, a task thatcan be likened to producing a uniform mixture ofsand and honey. Mixing is inherently dangerous,however, since accidents can cause large fries orexplosions; a mixing blade that scrapes anysurface can cause sparks that would ignite thefuel.The mixture must then quickly be cast into themissile case and allowed to harden and cure.Extreme care must be taken during casting toensure proper bonding of the propellant grain tothe case wall and to avoid the formation of cracksor voids. Such imperfections can expose additionalsurface areas within the propellant, causingit to burn erratically or reach the wall prematurely,resulting in catastrophic failure of the motor. Inaddition, the larger the motor, the more susceptiblesolid propellants are to the formation of cracksdue to repeated changes in temperature.Proper grain design is also important. Itshollow cross-sectional shape determines the amountof surface area burning at any time, thus influencingthe rate of burn, the internal pressure, and thusthe motor’s thrust. Design trade-offs must bemade between minimizing the change in chamberpressure during the burn, on the one hand, andavoiding excessively rapid acceleration at the endof the bum when the missile is lightest, on theother; too much of one or the other would putundue stress on the missile casing. During boost,the grain must also withstand extremely hightemperatures, pressures, and stresses of acceleration.As solid motors become larger, their engineeringand fabrication therefore become increasinglymore difficult.To verify their integrity and proper structure,solid motors are inspected after their manufactureby nondestructive methods such as x-rays, ultra-Blades of a highly specialized Iraqi solid-fuel rocketpropellant mixer being destroyed under the authorityof U.N. Security Council Resolution 687 during aninspection in 1992. Such mixers are used to preparethe fuel before casting it into the missile housing.sound, and thermal imaging. (The equipmentrequired for manufacturing a typical advancedsolid motor is given in table 5-5.) Skipping theseinspections would exact a price in terms of lowerreliability.| Obtaining Missile TechnologyPURCHASEUntil the 1980s, the majority of ballisticmissiles sold or traded were related to the originalliquid-fueled Soviet Scud-B, with at least eightdeveloping countries obtaining Soviet Scudsdirectly-Afghanistan, Egypt, Iraq, Libya, NorthKorea, Syria, and North and South Yemen (whichhave since united) .34 Notably, all of the indigenousmissile programs in the developing worldthat did not receive Scud missiles from the SovietUnion appear to have primarily (though notexclusively) pursued solid-fuel technology fortheir more advanced programs. These includeArgentina, Brazil, India, Iran, Israel, South Korea34 Scverd of thes~s~, Yemeu and possibly Libyt+-also obtained the more accurate @ut shorter We) solid-fueled SS-21. S= @ble5-3 and sources therein.

218 I Technologies Underlying Weapons of Mass DestructionTable 5-5-Typical Equipment for ProcessingComposite Solid PropellantsProcessReducing oxidizer crystalsize and blendingMixingCastingFabricating fiber-reinforcedcases or nozzlesInspecting to detect voidsor unbended areasTransferring componentswithin the plantTypical equipmentHammer mills; micropulverizers;fluid energy mills; sieves,screens, rotary dryersAutomatic 2-or 3-bladed rotaryvertical mixersCoated mandrels; bells; spoutsAutomatic filament-winding machineX-ray or ultrasound equipment;thermal imaging; manipulatorsSpecial vehicles or trailers forsemi-finished motors and mixedpropellantslurrySOURCE: Adapted from Tom Morgan, former group leader for counterproliferationand delivery vehicle systems, Lawrence Uvermore NationalLaboratory, presentation at SDIO Missile Proliferation Conference,System Planning Corporation, Rosslyn, VA, Apr. 4-10, 1992.Pakistan, South Africa, and Taiwan. No SovietScud recipients appear to have successfully developedsolid-fueled missiles with anywhere nearcomparable range to their liquid-fueled missiles,except possibly Egypt. 35Although the Soviet Union was the mainsupplier of ballistic missiles to the Third World,some secondary suppliers and traders of missilesand missile technology have emerged. 36 Theseinclude: North Korea, which received SovietbuiltScuds from Egypt, sold indigenously builtScud-Bs and Scud-Cs to Iran and Syria, andappears to be in the process of selling 1,000-kmNodong I missiles to Iran as well; Libya, whichtrans-shipped Soviet-built Scud-Bs to Iran andNorth Korea; Israel, which reportedly transferredLance missiles to Taiwan and Jericho missiletechnology to South Africa; Argentina, Egypt,and Iraq, who banded together in an unsuccessfuleffort to develop the Condor II missile; Brazil,which in the past has engaged in attempts todevelop and sell missiles to a number of countries,including Libya and Iraq; and China. 37North Korean and Chinese behavior regardingmissile sales have been particularly troubling tothe West, since both have long resisted calls toexercise restraint. China has maintained that thesale of missiles does not qualitatively differ fromsales by the West of high-technology jet fightersto countries in the same regions. Nevertheless, bythe end of 1991 China had agreed in principle toabide by the provisions of the MTCR and largelyaccepted the West’s judgment that both its M-9and M- 11 missiles exceeded the MTCR’s 300-km/500-kg threshold. 38Before this apparent change in policy, Chinesemissile sales and technical assistance had addednoticeably to missile capabilities in the MiddleEast and elsewhere. In 1988, China sold to SaudiArabia about 30 to 50 liquid-fueled 3,000-kmDF-3A missiles (called CSS-2 by the UnitedStates). These missiles have the longest range byfar of any sold to a Third World country.35 ~ addition to pmducing be solid-fuelti Sakr-80 (a copy of the Soviet FROG-7, an unguided missile with range less w 100 km), Egyptparticipated in the now-abandoned consortium with Argentina and Iraq to develop the two-stage solid-fueled Condor 1/ missile withapproximately 1,000-km range.36 ~ tie PMC tie u~t~ s~te:s ~ppli~ ~nce and Honesr.lohn missiles to Israel and South Korea, respectively, but siQce tie 197~ ~transferred missiles only to NATC) allies, and even these have had signifkant restrictions attached. The 1987 INF Treaty further constrainedboth U.S. and Soviet missile transfers. In 1991, Russia pledged to abide by the MTCR guidelines.37 -Pies ~ ~s ~MWph l~en fimw. Seti tis, Ba/lisdc Missiles in Modern Conflict (New York: meger, 1991), PP. 14.18, ~21; and Douglas Jehl, “Iran is Reported Ac@ring Missiles,’ New York Times, April 8, 1993, p. A9.38 me pledge by china to abide by the MTCR was made at the end of 1991 during a trip by then-Secretary of State Jwes A. Btier, ~.During congressional testimony in February 1992, Baker said tbat China’s pledge was “a very substantial and significant step forward, if theywill adhere to their commitment. If they don’t. . sanctions [on high-sped computers and satellite parts] will go right back on. ” In August1993, the United States found that China had in fact violated its commitment to observe MTCR constraints, and announced that sanctions-yetto be deterrnined-would be imposed. (See Stephen A. Holmes, ‘‘U.S. Determines China Violated Pact on Missiles,’ New York Times, Aug.2s, 1993, p. 1).

. .Chapter 5-The Proliferation of Delivery Systems | 219Although the DF-3’s accuracy is among the worstin the Middle East (CEP of over 2 km), thesemissiles have placed the entire Middle East andparts of the former Soviet Union within reach ofSaudi Arabia. Chinese technical assistance hasalso played a significant role in the missileprograms of North Korea, Iran, Brazil, andPakistan.According to various reports, certain Germanfirms in the past have also provided technicalassistance to missile programs in Argentina,Brazil, Egypt, India, Iraq, and Libya, and Frenchand Italian firms have helped with aspects ofprograms in Argentina, Egypt, India, and Paki-Stan. 39More recently, however, several countries thathad exported missile technology have been curtailingtheir assistance to foreign missile programs,and some are even becoming members ofthe MTCR. For instance, with the demise of itsCondor || missile program, Argentina agreed toabide by the provisions of the MTCR in May,1991, as did the Soviet Union one month later. Asof March 1993, Argentina was in the process ofbecoming a full member of the MTCR, and Brazilmay be considering joining. Each of these countrieshas had a history of either supplying missilesto developing countries or collaborating in missileprograms with them. The only state said bythe United States to be exporting MTCR-coveredmissiles today is North Korea. However, in lightof China’s reported export of M-11 missilelaunchers to Pakistan in 1991 and the more recentU.S. finding that China has violated its MTCRcommitments, it remains to be seen whether orhow well China will uphold the export constraintsdictated by the MTCR. 40A metal-rolling mill+me example of the type ofmultipurpose equipment that can be associated withballistic missile production. This and other missilerelatedequipment in Iraq were destroyed under U.N.auspices in 1992.EXPERTISE REQUIRED FOR INDIGENOUSDEVELOPMENTShort range missilesReproducing, reverse engineering, modifying,and launching short range missiles does notrequire a particularly complex or expensiveinfrastructure. Many countries that would havegreat difficulty assembling a well-trained groupof technical, operational, and tactical specialistsneeded to field an effective air force could stilldeploy a significant missile force. 41 (See box5-A.)The V-2 missile, designed and used extensivelyby the Germans during World War II,provides a baseline against which more sophisticatedballistic missiles can be compared. The V-2was the frost operational version of a class ofballistic missiles that led to the Soviet-designed39 see, for example, CarUS, Ballistic Missiles in Modern Conj7ict op. cit., footnote 37, pp. 22-23.@ See, for ex~ple, Jim - ‘‘Ctia Said to Sell Pakistan Dangerous New Missiles, ’ Los Angeles Times, Dec. 4, 1992, p. Al; and AnnDevroy and R. Jeffrey Smith, “U.S. Evidence ‘Suggests’ China Breaks with Arms Pact+” Washington Post, May 18, 1993, p. A9.41 ~w=d N Lut~~ foreword to CarUS, Ballistic Missiles in Modern Conflict, Op. cit., foomote 37* P. ‘ii.

220 I Technologies Underlying Weapons of Mass DestructionBox 5-A-Iraq’s Missile ProgramsOf those countries that have imported Scud missiles in the past, only North Korea and Iraq appear to havebeen successful at modifying and extending their range. North Korea has reportedly done so by a process called“reverse engineering”: disassembling the missiles, learning how to manufacture or modify their parts, andmanufacturing new missiles. 1 Iraq extended the range of its Scuds by taking sections from one missile’s fuel andoxidizer tanks and splicing them into other missiles. In this way, three missiles were cannibalized to make twolonger range ones. 2By mid-1990, Iraq possessed the Soviet-supplied *d-B missile (300-km range, 1-km CEP) @US twoindigenous variants-the Al-Husayn(600-km range, 3-km CEP) and the Al-Hijarah(75O-km range, unknown CEP,also called Al-Abbas-ali capable of carrying conventional or chemical warheads. Al-Husayn and Al-Hijarahmissiles, each about two meters Ionger than the original 1 l-meter Scud-Bs, were Iaunched toward targets in Israeland Saudi Arabia during the Persian Gulf War. From their launcher complexes, these missiles were capable ofreaching Tel Aviv, Haifa, and Israel’s nuclear facility at Dimona in the Negev desert. 3Despite the existence of a missile manufacturing center, however, it is likely that Iraq would still have requiredforeign assistance to fabricate precision missile components such as fuel-injector plates, turbo pumps, andguidance systems. 4 Since Iraq is known to have been importing many components and receiving foreign technicalassistance for its missile (as well as other weapon) programs, it is uncertain whether it could have manufacturedeven a Scud-type missile completely on its own at the time of the Persian Gulf War.1 J-s. ~rm~z, Jr., c4B~IiwG Ambitions Ascendant: North Korea’s ~iiStic Missile Pro9ram~ is aThreat to be Reckoned With,” Jw?e’s l%tbnce 14@ek/y, Apr. 10,1993, p. 20-22. Although Egypt and Libya have alsoboth worked on developing 300 to 700 km one-stage liquid-fueled missiles, and Egypt was invoived in the Contif//program, nothing isknowntohavebeen fietded so farfromtheseprograms. See, forexampie, Bermudez, “BallisticMissile Development in Egypt,” Jane’s /nfe//@n# Rev/ew, October 1992, pp. 452-458.2 W. ~th Cams and Jo~@ S. Ber~~z Jr., “iraq’s ‘Ai-Husayn’ Missile Programmed,” Jane’s Soviet/nte//@nce Review, vol. 2, No. 5, May, 1980, p. 205. Uquid-fueled missiles Iendthemselves to this teohnique, sincethe engines do not haveto change appreciably to accommodate Iargerarnounts of propellant and Iongerburn-times.3 U.S. ~ ~ ~fen=, ~~~t ~fthe P~s@ Gu/f War: ~n~~~rf to Congress, Pursuant to Title V ofthe Persian Gulf Confllct Supplemental Authorization and Personnel Benefits Act of 1991 (Pub! lcLaw102-25), April1992, p. 16. Note that many sources cdl the second modification of the Scud-B the A/-Abbas, and claim a range of900 km. Such a dismpancy could easily be explained by a difference in payload.4 Tom Morgan, former group leader for counterprollferation and delivery vehicle S@3mS, k~en~Uvermore Natjonal Laboratory, private communication, Dec. 20,1992.Scud. Its characteristics are summarized in table more complex. Expertise is therefore a key5-6.As missile range increases from under 1,000km to 2,500 to 5,000 km, there are generally atleast two principal hurdles: manufacturing thelarger propulsion systems needed to achieve thehigher velocities required for longer range, anddesigning missiles with more than one stage. 42Ensuring stable fuel combustion and flight characteristicswhile in the atmosphere also becomeingredient in developing long range missiles—especially having access to engineers and techniciansskilled in the areas of subsystem integration,testing, and production methods (see table 5-7 forone estimate of the personnel and time required)According to one experienced U.S. missile designer,a considerable amount of ‘art” is alwaysinvolved, especially for more sophisticated designs.Specifications and documentation can-4Z M&tiorMI desi~ problems lue Caused by heating of the missile skirL the internal components, the propelhm~ and the reen@y vehicle ma result of air friction at higher velocities.

Chapter 5-The Proliferation of Delivery Systems | 221View from the muzzle end (top) of the Iraqi‘‘supergun,” which Iraq installed and tested at JabalHarmayn, some 200 kilometers north of Baghdad.Using the experience gained from modifyingScuds, Iraq had also built and launcheda prototype of a crude space-launch vehiclenamed the Al-Abid, and claimed that it haddeveloped a 2,000-km range ballistic missilenamed Tammuz using similar technology. 5Iraq’s “Project Babylon’’-not a missile itself,but a program to develop a specialized 1,000mm-bore launcher or “Supergun’’-was partiallyimpeded by a British customs seizure ofparts and by the murder of Gerald Bull, itsprincipal designer. The supergun was beingdesigned to fire guided rockets with conventional,chemical, or possibly nuclear warheadshundreds of miles. 6 A 350-mm researchprototype had been completed and test- firedfrom a site about 120 miles north of Baghdad?5 The prototype missile appeared to have three stages. The first consisted of engines in an indigenously builtairframe (e.g., possibly dustered boosters). The second and third stages used for testing were Inert but wereinoluded for their weight and aerodynamic effects. See, for example, U.S. Dept. of Defense, Conduct of the PersianGulf War, op. cit., footnote 3, p. 20.6 U*SO Dept. of ~fense, ~~~uc~of~~e Per@an Gulf ~r, op. d~, footnote 3, p, n. Note, however, that ifsuch a missile launcher was intended to use guh%d rookets, nntch of its advantage would be lost (sinoe theprojectile’s ultimate accuracy would still depend on Its onboard guidance system), while it would subjeot the entireprojectiletoextreme acceieratkmsnotexperlenoed innormat mlsslletrajectorles. The’’ Super Gun” may have Indeedbeen better suited for placing small payloads into orbit, a task requiring less aoouracythan attacking ground targets.C. Robert Dietz, senior missile designer (retired), lakheed Missiles and Space Co., private communication, Dec.8, 1992. See aiso, Brigadier K.A. Timbers, “Iraq: Supergun-A Complex Matter,” Army Qwrtedy and DefenseJournal, vol. 22, April 1992, p. 149.7 IJ.S. Dept. of Defense, Conduct of the Pers/an Gu/f war, oP. Cit., fOOtnOtO 3, p. 20.not substitute for first-hand experience inballistic-missile design and manufacture. 43Nevertheless, foreign expertise in missile developmenthas been widely available in the past.Countries such as Germany and Italy, eventhough members of the MTCR, had not soughtuntil recently to restrict individual citizens fromassisting with missile projects in developingcountries. 44 Germany had not applied its exportregulations to weapon systems co-produced witha foreign firm, or to dual-use components, technologies,or manufacturing capabilities. Althoughrecent changes in German export control law nowforbid this type of assistance, the breakup of theSoviet Union may lead to additional new sourcesof expertise. 45Before the advent of the MTCR, other majorpowers also engaged in a variety of cooperative43 C. Robert Die~, senior tissile designer (retired), Imckheed Missiles and Space CO., private COmmunimtio% D=. 8, 1992.44 u,S. Gene~ ~cou~g O&Ice, U.S. Eflo~~ t. Control the Transfer of Nuclear-capable Missile Technology, Repofl tO &Xl. DeCOnCini(NSIAD-9(L176, June 1, 1990), p. 17.45 one ~cident ~ Octoba 1992 fllu~~a~g ~ese potenti~ ris~ involved RUsSi~ au~orities Stopping m RUSSkl el@eerS ad t&hniCiilIlsfrom departing to North Korea, reportedly to help with the latter’s missile programs.

222 | Technologies Underlying Weapons of Mass DestructionRangeWarheadWeightMaximum altitudeImpact velocityPropellantTable 5-6-Characteristics of theGerman V-2 MissileGuidance and controlFirst testedWorld War II usage240-300 km1,000 kg high-explosive (conventional)warhead12,900 kg fully fueled (twice that ofthe Scud); 4,000 kg empty80 km0.8 km/secBi-propellant liquid-alcohol andhydrogen peroxideGyroscopes for determining directionand velocity;a rotating vanesat ends of missile fins and rotatingheat-resistant vanes in exhaustjet1942, by Germany2,000 missiles against Britain, resultingin 1,500 deaths3,500 total missiles against citiesin England and on the continenta Experiments were also carried out, but no operational missilesproduced, using radio-ontrolled guidance.SOURCE: Gregory Kennedy, Vengeance Wapon 2: The V-2 Gu/dadMissi/e(Washington, DC: The Smithsonian Institute, 1983), pp. 70-73.efforts to develop Third World missile technology,including: 46In the late 1960s and early 1970s, Franceprovided sounding-rocket technologies andgranted licensed production rights to Indiaand Pakistan, in part to subsidize France’sown space-launch development costs; theFrench also assisted with missile-developmentprograms in Argentina, Brazil, andIndonesia.In the 1970s, the United States assistedSouth Korea in the construction of a Nike-Hercules surface-to-air missile manufacturingfacility, whose product was later modifiedby the Koreans for surface-to-surfaceuse. The United States also assisted India andBrazil in developing their sounding rocketprograms.In the 1980s, Chinese missile experts travelledto Argentina and Brazil to providetechnical assistance for their missile programs,as well as to promote sales of Chineseintermediate range missile technologies.In the past, missile technology has also beentransferred through sales and technical assistanceamong secondary suppliers themselves. Examplesof such transfers were provided in theprevious section. The foreign training of keyindividuals, too, has played a key role in missileprograms. For example, according to William H.Webster, then Director of the CIA, “In themid-1960s, the United States accepted a youngIndian scientist, Dr. Kalam, into a training programat the Wallops Island Rocketry Center. Thisscientist returned to India, and, with the knowledgegained from his work on the civilian spaceprogram, Dr. Kalam became the chief designer ofIndia’s Prithvi and Agni ballistic missiles. ” 47Hence, the proliferation of missile expertiseand technology for at least short range systemswas advanced by a variety of paths during the1980s, helping facilitate its acquisition by severalemerging missile powers. However, with theadvent of the MTCR, many of the mechanisms bywhich this technology transfer had occurred havebeen constrained. (See box 5-B.)Reentry vehiclesAs ranges increase beyond 1,000 to 2,000 km,a ballistic-missile warhead must be affordedgreater thermal protection to survive the heat46 See, for ex~ple, Stiord, ,4ssessing Ballistic Missile Prohferation, Op. Cit., foo~ote 4, pp. 9499.47 ~~ony of WilliaLU H. Webster, Director of Central Intelligence, in U.S. Senate, committee on Governmental AffairS, Nuclear atiMissile Prolferation, IOlst Congress, 1st Sessiou May 18, 1989, S. Hrg. 101-562 (Washington DC: U.S. Governrnent Printing Office, 1990),p. 12.

Chapter 5-The Proliferation of Delivery Systems | 223Table 5-7—Notional Personnel Requirements for Ballistic Missile DevelopmentDesign taskDesign first-generation liquid-fueled missiles (similarto Scuds)Personnel/time requirement5 to 10 well-trained and experienced combustionscientists, chemical engineers, heat transferspecialists, and experts in fluid mechanics andmechanical design, in a well-funded, multiyearresearch and development programDevelop simple flight-control systems tailored toa particular missile (for instance, rotating vanesmounted in the path of the exhaust gas)Manufacture Scud-like or longer range liquidfueledmissilesIndigenously design, develop, and produce firstgeneration(Scud-like) ballistic missiles fromscratch, starting from only a rudimentary industrialinfrastructureLearn how to manufacture solid-fueled rocketmotors of 1,500-km range or moreCarry out a thorough program of flight testingDevelop and produce a longer range, moreadvanced ballistic missile—if a relativelysophisticated industrial infrastructure were alreadyin placeAbout 20 mechanical, electrical, and manufacturingengineers and technicians, and about 5 to10 specialists to develop the guidance computerand software30 to 50 experienced machinists and techniciansTotal of 300 to 600 well-coordinated and experiencedengineers, technicians, and manufacturingpersonnelA team of at least 5 to 10 specialists with manyyears of propellant-processing experience, tomaster the largely empirical mixing and castingtechniquesRoughly 100 or more experienced personneland up to a dozen or more tests, plus specializedinstrumentation, radars, data acquisition systems,and test rangesAs few as 3 to 10 missile designers withhands-on experience could train local specialistswithin about 5 to 10 yearsSOURCE: Adapted from Stanford University, Center for International Security and Arms Control, Assesshrg Bal/isticMissi7e Pro/ifemfion and Ifs Control (Stanford, CA: Stanford University, November 1991 ), pp. 135,138, 140-141, 145,147.generated by reentry into the atmosphere. 48 In smoothly and predictably would be very difficultgeneral, such protective packaging-called a for most developing nations and, in any case,reentry vehicle (RV)-is coated with material would require extensive flight testing. 49that gradually burns off and carries away heat in To protect a warhead during its passagea process called ablation, thereby protecting the through the atmosphere, it is also possible to usewarhead inside. However, asymmetric ablation a blunt reentry vehicle. Manned space capsulescan cause an RV to steer itself far off course. are examples of blunt RVs designed to dissipateDeveloping ablatively coated RVs that erode reentry heat and protect astronauts. Blunt RVs48 ~em is one application us~g a nucIe= W=wn tit re@res neither accurate delivery nor a reentry vehicle. A nucl~ w~pon detomtedat high altitude can generate a powerful pulse of radio waves (called ‘‘electromagnetic pulse’ ‘), which can wreak havoc on some types ofelectronic equipment. However, this would not pose the kind of direct human health risk normally associated with weapons of mass destruction.49 s~o~, ASSeSSi~g Balzi$fic ~iSSi/e ~ro/iferarion, op. cit., foo~ote 4, p. 143. ~ical ~te~ ~ k ablative nosetips includefiberglass, carbon-phenolic, and carbon-ctubon composites.

224 I Technologies Underlying Weapons of Mass DestructionBox 5-B-Technology Transfer and the Condor II ProgramAlthough ballistic missiles rely on a number of multiuse technologies, some key technologies havecharacteristics uniquely identifiable with missile or space-launch-vehicie development programs. Such itemsinclude the hardware and software used in missile guidance systems, 1 special composite materials, largs speciallydesigned soiid-propellant mixers and casting apparatus, and rocket-motor static test stands. Restricting trade inthe suite of technologies most useful to developing missiles therefore provides some measure of control overmissile proliferation. Nevertheless, control of missile proliferation by restricting trade in certain materialsand technologies is Inherently more difficult than similarly controlling nuclear proliferation, since thereare more potential suppliers of missile technologies and fewer of the relevant technologies are uniquelymilitary in nature.The cancellation in 1991 of the Argentina-based Condor ll program, heralded as one of the successes of theMTCR regime, points broadly to the inherent difficulties involved in developing missiles with longer rangethantheScud. The 1,000-km -stage, solid-fueled Condor // missile, whose development may have been partlymotivated by Argentina’s defeat in the Falklands War, was to have been the product of a consortium betweenArgentina and Egypt, with financial assistance from Iraq. Each of the three states had previously developed orimproved the performance of short range missiles such as the Scud, with varying degrees of success. However,despite attempts to recruit technical assistance and to import goods from a number of firms in Europe and theUnited States, the Condor II project ultimately proved unable to acquire many of the technologies needed for acomplete system. in 1988, under pressure from the United States and constrained by the MTCR’s newly imposedexport restrictions, the consortium began to dissolve. By 1990 the program had ground to a standstill in all threecountries.Egypt’s involvement in the project sheds light on the extent of foreign assistance that was sought. 2 Beforethe Condor II project, Egypt had advanced little beyond modifying Scuds and making the 80-km unguided missilecalled the Sakr-80. However, in gearing up for the more ambitious Condor //, an organization known as theCONSEN Group 3 arranged on behalf of Egypt for a number of well established European firms to provide keycomponents:Messerschmitt-Boeikow-Biohm (MBB) of Germany-guidance systems and general missile technologyMAN of West Germany--wheeled transporter-erector-launchersSagem of France -inertial navigation systemsSNIA-BPD of Italy-rocket motors and solid-fuel technologyAdditional contractors, such as Bofors of Sweden, and Wegmann of West Germany.The long list of companies and technologies that Egypt and Argentina attempted to involve in efforts toadvance the levelofthe Coondor II missile in the l980s attests to the complexity of such an undertaking. From 1963to 1988, an Egyptian by the name of Abdel Kader Helmy (who became a naturalized American citizen in October1987) conducted on behalf of Egypt an ambitious program to acquire missile-related technology and components1 For}ns~~, missiieguidance andcont~ requirements are nwch more stringentthan the dmdepositionand veiodty information avaikbie from widely used airline and shipping navigation systems.2 M~ of the foiiowing is taken from Joseph S. Bermudez, Jr., “6aiii8tic ?di88iie ~vdop~ti ~ Egypt”Jane’s Intell@noe l?e~w, Ootober 199% pp. 456-45S. See also James Adams, Eh@nes of M&: Merchanfs ofDeath and the New Arms Race (New Yorlc NY: Atlantic Monthly Press, 1990), pp. 257-267.3 The two most important oompanies in the CONSEN Group for Egypt% participation in the @*pfO~were iFAT Corp. Ltd., of Zug, Switzerland (responsive for the finandai aspeots) and CONSEN SAM., Iooated inMonaco (responsible for contracting). Underthe direction of Egypt% Minister of Defense, an office toooordinatetheCondor //project was established in Salzburg, Austria lco-iocated with the offices of the CONSEN Group.

Chapter 5-The Proliferation of Delivery Systems | 225illegally from the United States. Helmy and his co-conspirators either exported or intended to export a wide varietyof missile-related items to assist Egypt’s programs for both the Scud and Condor//, including’!, A fully instrumented test-stand for analyzing rocket motors of up to 20 tons thrust● Strap-down inertial guidance systems for the Con&//, and software for their optimization● Fuel-air explosive warheads for the Condor // 5● Carbon-carbon and ceramic-composite materials to be used in Condor // nose cones● Various chemicals for composite solkf-propellant rocket motors:18,000 lbs. of militarygrade aluminum powder11,000 lbs. of the synthetic rubber HTPB (hydroxyl-terminated polybutadiene)500 lbs. of EPON from the Miller-Stephenson Co., used in the aerospace industry for gluingcomposite fabrics to surfacesEpoxy-hardeners from the Hemkel Co.40 lbs. of MAPO (tris-2-methyl aziridinyl phophine oxide), a soiid-propellant additive, from Arsyncoco.HMDI (hexamethylene diisocyanate), a curing agent for HTPB● 21,200 lbs. of maraging steel intended for the motor casing of the first stage and connecting segments185 yds. of Rayon-based ablative carbon fabric from the HITCO Co. for heat-shiefds to protect Condor //payloadcovers■ 436 lbs. of MX-4926, an ablative carbon-phenolic fabric from the Fiberite Co., essential for manufacturing theflexible nozzles the Condor // was to use for maneuverabilityMicrowave rocket telemetry antennas from Vega Precision LaboratoriesThe majority of these efforts failed, however, and Helmy and a number of his collaborators were eventually arrestedin June 1986. The loss of a U.S. conduit for missile technology imposed a staggering blow to the Egyptiancomponent of the Condor //projct. Within months, both Egypt and Iraq had ended their involvementwith project.A Bermudez, “Baflistic Missile Development In Egypt,” op. dt, fOOtnOtO a, p. X57.5 Ap~orattempt in 19S4 by the Egyptian Ministry of Defense to imfKN’tOOmpOnOntS for f@-~r exPfoSves ‘adbeen blooked by the U.S. State Department and Customs Servfoe beoausethe parts were on the Munitions ControlList.were also used with early U.S. ICBMs such as theAtlas. Exotic ablative materials are not nearly soimportant for blunt RVs, since air resistancequickly decelerates them to speeds slow enough ■for ordinary materials to withstand the heatgenerated during reentry. However, in employingblunt RVs, accuracy is lost both from self- ■steering and from atmospheric winds having arelatively larger effect on a slower moving RV.Their use could easily result in a loss of several ■kilometers or more in accuracy.Long range missiles and ICBMsAlthough several systems have been developedfor categorizing ballistic missiles with rangesgreater than 300 km, the U.S. Department ofDefense classification system provides a usefulreference:Short range ballistic missiles (SRBMs) haveranges up to 1,100 km, or 600 nautical miles(nmi),Medium range missiles (MRBMs) haveranges from 1,100 to 2,750 km (600 to 1,500nmi),Intermediate range ballistic missiles(IRBMs) travel from 2,750 to 5,550 km(1,500 to 3,000 nmi), 50 and■ Intercontinental range ballistic missiles(ICBMs) can reach from 5,550 to 14,800km(3,000 to 8,000 nmi).~ me bte~~ate rmge NucleaI Fomes (INF) Treaty categorized all surface-t~surface ballistic aud cruise fiSsiles with ~geS be-n500 and 5,500 km as “Intermediate Range”.

226 I Technologies Underlying Weapons of Mass DestructionWith nominal payloads of roughly 500 to 1,000kg, SRBMs are generally single-stage, meaningthat they have a single set of (possibly clustered)rocket motors that is carried throughout the flight,even after its fuel is expended. 5l Multistagerockets, in contrast, are powered by successivesets of rocket motors, each of which is jettisonedwhen its fuel burns out. IRBMs and ICBMS arealmost always multistage. 52 MRBMs are anintermediate case, typically consisting of eitherone or two stages.Making the transition from a short rangeballistic missile capability to being able to designand produce ICBMs involves a number of substantialtechnological hurdles. Iraq increased therange of imported Scuds from 300 km to between600 and 900 km by cannibalizing and rejoiningsections from different missiles to create longerones, while simultaneously reducing the payload.But such methods would not work to createICBMS. 53Developing accurate and reliable ICBMs—which would almost always be multistagepresentsinherently new and drastically morecomplex difficulties than simply extending therange of Scuds. The following factors make theengineering and design of long range missilesdifficult. 54Staging. Proper mating of the stages andgetting them to detach and fire at precisely theright moment adds considerable complexity tothe design. (Once the missile leaves the atmosphere,the missile can easily begin to tumble at thestage transition, because aerodynamic forcescannot be utilized to stabilize it.) Staging alsoincreases the difficulty in designing the missile’sflight control systems, while it generally decreasesreliability, accuracy, and mobility.As a partial alternative to staging, strap-onclusters of boosters can be and have been used toincrease the range, possibly at considerably lessexpense than developing larger boosters. However,in addition to stability and reliability problemscaused by using boosters not originallydesigned to be clustered, the potential increase inrange would remain quite limited. In most cases,staging would still be required to reach ICBMranges. 55Structure and Materials. To withstand thelarge forces caused by their greater launch-weightand stresses in the atmosphere, longer rangemissiles must incorporate stronger materials than51 ~ genemte enough tit to lift ahavy missile, the (fret) Wge must expel prOpdhUlt es at a ~mendo~lY ~hm~~ a %eand thus heavy motor. But since the motor must be accelerated along with the rest of the missile, its own mass limits the speed it can achieve.(The same limits apply to strap-on boosters.) Only by abandoning a fret-stage spent motor and then f- a subsequent stage can a missileeasily achieve the velocities necessary for ranges in excess of a few thousand kilometers.52@ exception is me U.S. Atlas missile, fnt tested in the early 1950s and deployed in the km 1950s, which achieved I0,00@kIu -ewith essentially one stage. Although it generated additional thrust by burning fuel after the iirst-stage-f~ was complete, it did not releasethe fust stage motor or housing. Fueled by kerosene and liquid oxygeq the Atlas used such a thin walled canister on its main stage that it couldnot reliably support its own we@t in launch position until it had been properly loaded with fuel and pressurized.~s ~cr~ing tie s~c Of the ficl tanks on a given stage canordy go so far toward increasing amissile’s range, sin~ ti ovendl missile wU@Lincluding the additional fuel, would at some point become greater than the missile’s thrust thus inhibiting liftoff. Moreover, adding length orweight can cause undesirable and sometimes unstable flight characteristics by altering the aerodynamic stresses, causing the missile to bendand flex, and changing the moment of inertia.54 see *0, ~mLWF, ~s~~ ~~~d, ~d David C. Wright, ‘Third World Missiles Fall Sho~’ Bulletin of the Atomic ~c~endsts, vol.48, No. 2, March 1992, p. 36.55 potenti~ probl~with Smp@-tOgc~rbooS~rs include stability of the flight-control syst~ interference between the CXhUSt PIWES,excess heatgeneratiom and thrust cut-off errors that can lead to large inaccuracies, One analyst has estimated that by strapping togetherA1-Abbusextended range Scudrnissiles to carry a single 350-kg payload, one could achieve the following ranges: 1 booster-700knu 3 boosters, droppingfmt two at burn out—1,500 knx 5 boosters, dropping first four at bum out—2,200 lmq 7 boosters, dropping fmt four, then two, at respectivebum outs-5,100 km. James R. Howe, Rockwell International, Space Systems Divisiom “Emerging Long Range Threat to CONUS,” briefiipackeg December 1992. Note that this last example is essentially a three-stage missile, but still does not achieve ICBM ranges.

. - —Chapter 5–The Proliferation of Delivery Systems I 227those used in the Scud, usually requiring advancedcomposites or alloys.Fuel-fraction. Only about 75 per cent of arocket engine’s weight can be propellant ifmaterials and technologies comparable to thoseused in the Soviet Scud missile are employed. Thegreater the fuel fraction, the greater the range;therefore, a low fuel-fraction puts limits on therange a missile can achieve even if multistage.(Modern ICBMs achieve up to about 90 per centpropellant in each stage.)Reentry vehicles. ICBMs reenter the atmosphereat higher speeds than shorter range missiles,making it considerably more difficult to protecttheir warheads from atmospheric heating.Accuracy. Longer range missiles typicallyhave correspondingly longer boost times which,for the same guidance system, would result inlarger errors in bum-out velocity. These guidanceerrors then accumulate over longer flight times,increasing a missile’s miss-distance. More accurateguidance and control systems are thereforerequired.SPACE-LAUNCH CAPABILITIES AS A ROUTE TOBALLISTIC MISSILESInstead of developing ballistic missiles directlyor reverse-engineering short range missiles, acountry might also try to attract foreign assistancein developing a space-launch capability. 56 Atleast five nations besides the United States andthe former Soviet Union now have indigenousspace-launch capabilities: China, France (whoseAriane launchers have been developed and operatedin conjunction with the European SpaceAgency), Japan, India, and Israel. Brazil andPakistan are also developing space-launch orsounding-rocket programs. Much of the technologyused in sounding rockets and space-launchvehicles is directly applicable to surface-tosurfacemissiles. Hence, countries such as Brazil,India, and Pakistan have used civilian programsand foreign assistance to build expertise needed todesign and build their own military systems.Israel’s civilian and military programs are alsoundoubtable linked; the Shavit space-launch vehicleis widely reported to be a version of theJericho II missile. 57 Although the space-launch orsounding-rocket programs of South Korea, Taiwan,and Indonesia do not appear to haveprogressed significantly in recent years, theseprograms have also received foreign technologyassistance.Some analysts have concluded that there are nolonger any valid economic reasons for newcountries to develop space-launch vehicles, andhence that the United States should not providetechnical assistance to these programs. 58 However,this argument may give too little weight tothe possible prestige value or hopes of technologytransfer that could result from developing aspace-launch capability. It also minimizes thereluctance nations may have to depend on othernations for space-launch services. Countries mayalso be motivated to develop the capability tolaunch satellites for military communications orreconnaissance-goals that are not civilian butfall short of developing offensive weapondeliverysystems.Space-launch vehicles differ substantially fromballistic missiles intended for ground targets intheir requirements for accurate guidance andreentry technology. Space payloads do not requirereentry vehicles and rarely require extremelyprecise orbits, meaning that space-launch vehiclesneed not have as sophisticated guidancesystems as long range ballistic missiles. Boost-56 me ~atc-i~ ~ fi~ ~mwaph is Primtily ~en from CarUS, Ballistic Missiles in Modern COnfliCt, Op. cit., foo~ote 37, PP. 13, ’25.ST Some ~ysts ~heve t~t tie Sbvit space-la~ch vehicle incorporates technology tit the Israelis could use to bufld ~ I~M (~~useful weapon payloads and accuracy) with range in excess of 5,000 km. See, for example, Steven E. Gray, “Israeli Missile Capabilities: AFew Numbers to Think About,” Lawrence Livermore Natioml Laboratory, unpublished memorand~ Oct. 7, 1988.56 See, for exmple, Brim G. Chow, Emerging National Space-Launch Programs: Economics and safeg~rds, W RePofi ‘o.R=1179-USDP, January, 1993.

228 Technologies Underlying Weapons of Mass Destructionphase inaccuracies resulting in errors of tens ofkilometers at apogee may be easily tolerablewhen placing a satellite in orbit, but they can besignificant for surface targets even with weaponsof mass destruction. Moreover, space-launchvehicles are usually launched from specific locationsand can take weeks or months, if needed, toprepare for launch. Ballistic missiles, on the otherhand, are much more useful militarily if they canbe launched on short notice and are not restrictedto freed launch-sites.Still, ballistic missile technologies such aslarge boosters and high-quality guidance systemscould be tested and developed under the guise ofa well-developed space-launch program. A countrythat has demonstrated the capability todevelop space-launch vehicles should thereforebe considered capable of developing ballisticmissiles as well.COSTS OF MISSILE PROGRAMSShort range missiles, such as Scud-Bs orSS-21s originally from the former Soviet Union,cost as little as $1 million apiece to produce. 59 Atthe other extreme is the Saudi purchase of DF-3missiles from China, which reportedly cost $2billion for 30 to 50 missiles and their associatedlaunchers. 60 Even if the missiles in this purchaseaccounted for only half of the total cost, theywould still cost over $20 million apiece. Togetherwith launchers, this begins to approach the unitcost of acquiring advanced strike aircraft.Producing missiles indigenously can also beextremely expensive. Press reports have indicatedthat the Saad-16 missile-development complexbeing built in northern Iraq (reportedly with thehelp of several West German companies) mayhave cost Iraq $200 million. 61 Estimates suggestthat it would have cost Argentina $3.2 billion todevelop and produce 400 Condor II missiles, anddevelopment costs alone may have been destinedto exceed $1 billion. 62 Without financial assistancefrom other states, such costs would remainprohibitive for many of the countries of proliferationconcern.I Weaponization and DeploymentNAVIGATION, GUIDANCE, AND CONTROLSYSTEMSAs missile range is extended beyond a fewthousand kilometers, the inaccuracies of lesssophisticatedmissile systems could begin toexceed several-kilometer CEPS, 63 which couldaffect targeting plans even for weapons of massdestruction. However, for most scenarios involvinga proliferant country using or threatening touse a nuclear weapon, or even a terror attack withchemical weapons against another country’s territory,it would matter little whether its missiles’CEPs were measured in meters or kilometers.Guiding a missile to its target requires knowingprecisely its orientation, position, and velocity—at least throughout its boost phase-and theability to control its thrust to compensate forunexpected deviations in trajectory. (It also requiresknowing precisely the locations of thelauncher and target.) Guidance systems used bymost ballistic missiles rely on inertial navigationsystems to provide boost-phase information. Standarddesigns consist of gyroscopes, whose spinningcomponents resist change in their orientationand thus provide a freed reference frame, andaccelerometers, which in principle utilize weights59 Stiord, Assessing Ballistic Missile proliferation, Op. Cit., fOOtnOte 4, P. 45.w Ibid., p, 95.61 See cm, Ballistic Missiles in Modern Conjlict, op. cit., fOOtnOte 37, p. 22.62 Ibid., p. 64.63 For emple, tie 2,500-IcxII n~e Chinew cSS-2 (DF-3) missile has a CEP of about 2.5 m and the Iraqi AZ-~O”araMAMas ~ssfle, ~extended range Scud with a range ofonly 900 km has been estimated to have a CEP of over 3 km (2 to 3 miles). See, for example, World Mi/iraryExpenditures and Arms Transfers, 1988 (Washington DC: Arms Control and Disarmarn ent Agency, 1989), pp. 18-19.

Chapter 5-The Proliferation of Delivery Systems | 229attached to precisely calibrated springs. Wellbefore the advent of computers, Germany devisedan inertial guidance system for the V-2 missilethat combined gyroscopes with electrical capacitorsand electro-mechanical actuators to sendflight-controI information to the missile fins.Compact computers, however, are now used inessentially all modern inertial guidance systems.64Adapting inertial navigation systems originallyintended for aircraft or ships for use in missiles isproblematic for several reasons. First, they maybe too heavy or too large. Second, their performancemay be degraded by a missile’s highacceleration. And third, it may be impossible toalign their orientation precisely enough to achievethe accuracy needed for missile guidance. Similarly,straightforward application of NAVSTARGlobal Positioning System (GPS) informationwould be inadequate for keeping a missile orientedprecisely enough during boost-phase forgood flight control, and would only be useful iflate boost-phase corrections or a post-boost vehiclewere used to correct for any trajectory errorsmeasured by GPS. (GPS is discussed in moredetail in the cruise missile section below.)Furthermore, in order to make use of navigationinformation, the guidance system (whichcomputes the missile’s position and orientation)must be connected to the missile’s flight-controlsystem, which adjusts the missile’s trajectoryduring the boost-phase. Accuracies (due to boostphaseerrors alone) better than about 0.3 per centof range 65can only be achieved with modemcomputer-controlled guidance packages that incorporateprecise knowledge of the missile’sresponse-times and steering forces. Precise un-United Nations Special Commission inspectorexamining the tail section of an Iraqi modified Scudmissile, showing its heat-resistant vanes mounted inthe exhaust path and its rotating tail fins.derstanding of the behavior of flight-controlsystems is required to avoid unstable flightmaneuvers and over- or under-steering the missile.Slight flexing of the missile during boost canalso be difficult to compensate for, even withsophisticated control systems.Advanced computer algorithms coupled withextensive flight testing can be very helpful inunderstanding and overcoming the biases ofguidance system hardware. Coupling the guidanceand flight control systems, however, hasproven to be a major problem for many missileprograms in developing countries, including thosein Argentina and Brazil. 66 More advanced flightcontrol systems relying on gimballed engines forliquid-fueled motors, or high-temperature flexiblejoints at the nozzle exit-cones of solidboosters, would also be difficult for developingcountries to master in the short run.64 ~ ~ditiom tie utit~ Swtes ~d otier countries with advanced avionics industries have developed fig-laser gyroscopes for We asguidance systems in both missiles and advanced combat aircraft such as the F-16. These not only provide greater accuracy, but, since they havefar fewer moving parts, can be readied for launch much more quickly than traditional gyroscopes.65 Expressing a~wacy as a percentage of range is only a very approximate description of the effects Of error factors. Sfice ~ese erro~contribute indifferent and often nonlinear ways to miss-distances at the target, such percentages are used only for convenience and are not meantto imply a direct proportional relationship between accuracy and range.66 See, for ex~pie, Andrew Slade, “Condor Project ti Disarray, ” Jane’s Defense Weekly, Feb. 17, 1990, p. 295.

230 I Technologies Underlying Weapons of Mass DestructionMoreover, boost-phase guidance errors areonly one contribution to the inaccuracy of ballisticmissiles. For all but the shortest range missiles,the midcourse and reentry phases can contributesignificant and sometimes unpredictable errors,resulting from:reentry vehicles steering off course, in muchthe same way that skydivers steer with theirarms and legs (steering and lift forces can becaused by the RV’s oscillating or tumblingwhen it first encounters the atmosphere, orby unexpected rates of RV ablation); 67■ barometric pressure and weather over thetarget; and■ unmodeled anomalies in the earth’s gravitationalfield.In sum, accurate and reliable guidance,control, and reentry-vehicle systems for large,multistage ballistic missiles require integratinga set of critical technologies that wouldappear to be particularly difficult for developingcountries to master. To the extent thatreliable delivery of a weapon within severalkilometers of its target matters, these difficultiesprovide an important barrier to the proliferationof long range missiles in developingcountries. Barring direct purchase, progresstoward long range missiles will come in measuredsteps at best, and sudden breakthroughsare unlikely.MOBILITY AND SURVIVABILITYMost missiles deployed in Third World countriescan be launched from mobile wheeled ortracked vehicles known as transporter-erectorlaunchers(TELs). (Even ICBMs, such as theRussian single-warhead SS-25 and the U.S.Peacekeeper, can be put on mobile launchers andhidden.) Such launchers can be very difficult tolocate and track and can be stored in securelocations, making them less vulnerable to preemptiveattack. Syria reportedly stores its TELs inspecially constructed, fortified tunnels, and SaudiArabia may protect its DF-3 missiles by storingthem in a chosen group of bunkers that are basedon a design China uses to protect its strategicmissiles. 68 In the Persian Gulf War, the mobilityof the Scud launchers proved to be much more ofa problem for the allied forces than had beenanticipated. Even with the combined benefits ofmassive air superiority, the most advanced reconnaissanceand targeting systems available, andhundreds of sorties flown each night, an extensiveair-power survey carried out for the U.S. AirForce has found that although a few mobile Scudlaunchers may have been destroyed by coalitionaircraft or by special operations forces during thewar, there is no hard evidence that coalition airattacks destroyed any Iraqi Scud missiles ormobile launchers. 69Mobility comes at some cost, however. Whileit adds flexibility in choosing a launch site, itcould require developing a reprogrammable flightcontrolsystem to adjust missile trajectories. 70Long range missiles are significantly harder tomake mobile than shorter range ones; many roads,bridges, and tunnels may not be capable ofhandling the weight and size of a long rangemissile, and off-road transportation would proba-67 Rcen~ enors ~Ve beenreduced in tie united States and other countries with advanced missile programs, however, by extemlve tW@,computer modeling, use of techniques such as spinning the RV after properly aligning its axis, and using exotic materials to optimize nose-tipablation.68 c~s, Ballistic Missiles in Modern conflict, op. cit., footnote 37, p. 42.69 Eliot A. Cohen, Guf War Air Power survey (Washington, DC: School of Adv~Ced bte~tional !hdieS, JOkS HOPM U~V., ~~April 28, 1993), ch. 3, pp. 23,31-32. See also, Julie Bird, “GuifAirsrrikes Left Scuds lmac~” Defense News, vol. 8, No. 19, May 17-23, 1993,p. 26.70 Reprogr ammableflight-control systems would not be essential, however, since one could always keep a missile’s rangefmed by restrictingits launch to an arc centered on a fixed target; for liquid-fueled missiles, one could compensate for the differences in range by adjusting thepropellant level before launch.

Chapter 5–The Proliferation of Delivery Systems | 231bly be quite s10W. 71 Nevertheless, any countrywith experience in manufacturing large heavydutyvehicles, railroad cars, and constructionequipment such as cranes, should be able toconstruct at least primitive mobile launchers forshort range missiles. Therefore, mobile launcherswould not present a major hurdle for an emergingmissile power.OVERCOMING DEFENSESTo date, the only use of ballistic missiledefenses in wartime occurred during the PersianGulf War, in which Patriot defense batteries wererapidly deployed to Israel and Saudi Arabia tocounter Iraqi Scuds. 72 Over the six weeks of thewar, 81 Scuds were reportedly launched by Iraq,43 of which were targeted on military facilitiesand populated areas in Saudi Arabia, with theremainder against Israeli cities, About 47 Scudswere engaged by Patriot missiles. Claims madeby the U.S. Army and Raytheon, the manufacturerof Patriot, over Patriot’s success rate were initiallyquite optimistic. However, these claimsgenerated much controversy and have since beenrevised downward several times .73Few if any lessons from the Patriot-Scudengagements can be applied to the problem ofmissile defense in general, since both offensiveand defensive systems will continue to evolve.Nevertheless, it was instructive that one of thesimplest and indeed lowest technology forms of“penetration aid” probably played a role inreducing the effectiveness of Patriot. The Scudrocket casing, which remained with the warheaduntil late in reentry, tended to break up in thelower atmosphere, creating a much more difficulttarget for the Patriot to intercept. According to anengineer from the Raytheon Company who hashad nearly two decades of involvement with thePatriot system,Due to design changes and poor workmanshipwhen the Scuds were modified, they broke apartin midair and created the combined effects ofstealth, maneuvering reentry vehicles (RVs),decoys and fragments, and reduced warheadvulnerability. All were unanticipated and addedto the difficulty of defeating these TBMs [tacticalballistic missiles]. The inference of those whoclaim that because these TBMs were crude theywere easy to defeat is incorrect. 74Simple measures might therefore be adequateagainst a defense system not designed to discriminatedecoys, To protect against mid-courseinterceptors or associated radars, decoys could berather primitive; dispersing bundles of radarreflectingwire known as chaff might suffice.However, penetrating advanced terminal defensesmight require more realistic decoys having aerodynamicproperties similar to those of the warhead.Deploying such decoys would imposesignificant weight penalties.Development work is now vigorously beingcarried out in the United States and in Israel on avariety of improved antitactical ballistic missilesystems (ATBMs), including, for example, nextgenerationPatriots (called the PAC-3), a theater71 Udess ~eat cue is taken to dampen shocks and vibrations, transporting medium- and long range soZid-propellant missileS may alsodamage the fuel graiq resulting in loss of reliability.72 Several missile-defense systems had previously been deveIoped by the United States and Soviet union (and deployed, ~ the 1atter case),but all of these had used nuclear warheads, and none had been used in wartime.73 See, for exmple, U.S. Congess, House Committee on Government Operations, Subcommittee on Legislation and Natioti Stity,Performance of the Patriot Missile in the Persian Gulf War, 102nd Congress, 2nd Session, Apr. 7, 1992; and U.S. Congress, GeneralAccounting Office, Operation Desert Storm: Data Does Not E~”st to Conclusively Say How Well Patriot Pe#ormed, NSIAD-92-340(Washington, D. C.: U.S. General Accounting OffIce, Sept. 22, 19!32). See also Representative John Conyers, Jr., “The Patriot Myth: CaveatEmptor,” Arms Control Today, vol. 22, No. 9, November 1992, pp. 3-10; Theodore A. Postol, ‘‘Lessons of the Gulf War Experience withPatriot, ” International Security, vol. 16, No. 3, Winter 1991~2, pp. 119-171; and Robert M. Stein and Theodore A. Postol, “Correspondence:Patriot Experience in the Gulf War, ” International Security, vol. 17, No. 1, S ummer 1992, pp. 199-240.74 Robert M. Stein, mger of Advanced Air Defense Programs for the Raytheon Company, ‘‘Patriot ATBM Experience in the Gulf War, ’article sent to subscribers of Znternarionul Security, Jan. 9, 1992.

232 I Technologies Underlying Weapons of Mass Destructionhigh-altitude area defense interceptor (calledTHAAD), and Israeli Arrow interceptors. Althoughone or more of these systems or othersmay eventually provide some level of regionaldefense against ballistic missiles carrying conventionalweapons, even very small leakage ratesagainst missiles carrying weapons of mass destructioncould have devastating consequences.The potential effectiveness of defenses againstthe latter type of threat is therefore highlyspeculative at the present time.COMMAND, CONTROL, HANDLING, AND SAFETYREQUIREMENTSAs was stated earlier, the infrastructure requiredto support a missile capability is smaller thanthat needed to sustain an effective air force. Duringthe Iran-Iraq war, for instance, Iran was unable toacquire manned combat aircraft, but did manage toobtain and launch missiles under the control of theIslamic Revolutionary Guard, a force without aparticularly high level of technical expertise. 75Furthermore, targeting requirements at least forweapons of mass destruction would not presentmuch of a problem, since published maps orcommercially available satellite imagery wouldprobably suffice in most cases.Without its own reconnaissance aircraft orsatellites, however, a country using missiles todeliver weapons of mass destruction may notknow whether they landed anywhere near theirintended targets, and might have to rely on newsreports or spies to know the extent of thedestruction it had caused. (For this reason, Israelimilitary censors restricted reporting during thePersian Gulf War about Iraqi Scud strikes inIsrael.) 76Great care must be taken in transporting liquidrocket fuel or fielding mobile missiles to avoidaccidents that could lead to explosions. However,transporting weapons of mass destruction wouldalso warrant strict safety and security measures,so that the incremental safety requirements forhandling the missiles would probably not addsignificant additional obstacles.TESTING REQUIREMENTSEnsuring the reliability of the complex thermodynamic,aerodynamic, and electro-mechanicalsystems involved in ballistic missiles requiresextensive testing, both at the subsystem level andin full-scale tests. The engines can be tested inspecialized static test stands on the ground, butmissile guidance, control, and overall reliabilityassessments require flight tests. For instance, it isreported that after the initial flight test of China’sfrost medium range missile (the 1,200-km, singlestage,liquid-fueled CSS-1) failed in 1962, seventeenground tests were performed before a seriesof three more flight tests (all successful) werecarried out in 1964. 77 A thorough program offlight testing would involve specialized instrumentation,radars, data acquisition systems, andtest ranges. If the intended payload were veryexpensive, such as a nuclear weapon, a high levelof reliability would probably be desired, makingshort-cuts in missile flight-testing unwise andunlikely. Still, even well-developed and thoroughlytested missile systems are often stillconsidered to be only about 80 to 90 per centreliable .78If a missile is to carry and disperse decoys andother penetration aids to help it overcome defenses,an additional development and testing75 CmS, Ballistic Missiles in Modern Conjlict, op. Cit., footnote 37, p. 30.76 See, for example, “Missile Fired at Israel, ’’New York Titnes, Feb. 1, 1991, p. 11. Also, during World War KI, the British used double agentsto carry false information to the Germans about the impact points of V-1 and V-2 missile attacks on Imndon. See David Irving, The Mare’sNest (Boston: Little, Brown and Company, 1964), pp. 250-251.77 ~llip S. Cla.r~ “Chinese Launch Vehicles-’ Chang Zheng l’, ” Jane’s Intelligence Review, November 1991, p. 508.78 SW us. Con=ess, Office of I&koIoW Assessmen~ Access to Space: The Future of U.S. Space Transpotiation sYs@~, o~-Isc415(Washington DC: U.S. Government Printing Office, April 1990), p. 22.

Chapter 5-The Proliferation of Delivery Systems | 233program might be needed to develop them.Depending on the sophistication of the defenses,however, such a program to develop penetrationaids would probably not be nearly as complex asdeveloping the missiles and reentry vehiclesthemselves.IMPLICATIONS OF GPS AND NEW GUIDANCETECHNOLOGIESOne way a country might try to improvenavigational accuracy is through incorporatingGlobal Positioning System (GPS) data into amissile’s guidance system (see section on CruiseMissiles, below, for a discussion of GPS capabilities).However, this presents two inherent difficulties.First, to comply with MTCR guidelines,GPS receivers for commercial or export salesmust shut themselves down if they compute thatthey are traveling faster than 515 m/see or are atan altitude above 18 km. Since even 300-kmrangeScud missiles reach speeds of more than1,500 m/see and altitudes around 30 km beforeburnout, commercial GPS receivers would be oflittle use either in boost-phase or beyond. Nevertheless,if a country could manufacture its ownGPS receivers, or obtain the underlying electronicprocessor chips from elsewhere, this part of theproblem could be avoided.The other problem with using GPS systems formissile guidance, however, is common to allmissile systems: accurate navigational informationmust be translated into effective flightcontrol. GPS could be of great help with rapid andaccurate initialization of the missile’s positionbefore launch, and to some extent with determiningtrue north, both of which could be importantcontributions. But GPS information alone wouldprobably not help reduce the remaining uncertaintyfrom inertial guidance-system measurementsin the missile’s orientation at the momentof thrust termination, when the missile is movingand accelerating most rapidly. Even during theboost phase itself, it is would be technicallycomplex to transform GPS position and velocityinformation via the flight control system intouseful adjustments in the missile trajectory,especially given the slow rate at which most GPSreceivers update their readings. During boostphase, therefore, employing GPS data wouldprobably not be of much help in producing moreaccurate missiles.In theory, a post-boost vehicle could use GPSnavigational data to greater advantage in makingleisurely mid-course corrections outside the atmosphere.But a post-boost vehicle represents anadditional missile stage with its own propellant,thrusters, and computational power; and it wouldpose an additional obstacle for emerging missilepowers.Terminal guidance, or steering a warhead to aprecise aim point after it has reentered theatmosphere, has been employed on some advancedU.S. missiles (the Pershing II, for instance),but it would be exceptionally challengingfor an emerging missile power to develop.In sum, designing and producing reliable andreasonably accurate ballistic missiles of over1,000-km range would be difficult but not impossiblefor many developing states. There may beincreasing numbers of scientists from the formerSoviet Union and elsewhere willing to assist inthese efforts. Without dedicated resources andsome outside technical assistance, however, aprogram would be lengthened substantially andlikely encounter frequent setbacks. As missilerange and size are increased, almost all aspects ofmissile development (e.g., combustion chambers,casting of solid propellants, multiple staging,guidance and control systems, reentry vehicles,and even transporters) become increasingly complexand technologically demanding. Consequently,achieving accuracy and reliability forsuch systems requires more time and expense andcannot be assumed to follow on the heels offirst-generation missile deployment.| Monitoring Ballistic Missile ProgramsIntelligence capabilities for discovering ortracking missile transfers have been far from

234 I Technologies Underlying Weapons of Mass Destructionperfect. It was reportedly largely by accident thatU.S. intelligence sources discovered the Saudipurchase of Chinese DF-3 missiles, and then atleast two years after the fact. 79 It has also beenreported that the United States was unaware of theextent to which Iraq had successfully extendedthe range of its Scud missiles during the 1988Iran-Iraq ‘‘War of the Cities.’ ’ 80Missile development programs also draw onmany dual-use goods that have legitimate industrialapplications, making them difficult to controland monitor. These include forging, rolling, andother large metal-working equipment that couldbe used in manufacturing large motor cases, aswell as computers and certain types of precisioncomputer-controlled equipment. 81Nevertheless, production facilities for largemissiles and especially for solid-fueled boostersmight have distinctive characteristics that couldfacilitate their identification and monitoring.These features might be associated with their sizeor their capability to withstand accidental detonations.82 Accidental explosions themselves mightalso be possible to monitor. Furthermore, for thevast majority of developing countries, developmentof longer range missiles would require thatsignificant amounts of specialized hardware,materials, or technical assistance be imported,thus providing other governments a possiblemeans to monitor the program’s progress. It istherefore much more difficult to develop longerrange missiles in secret than it is to secretlyimport medium range missiles or extend the rangeof short range missiles.FLIGHT TESTING OF BALLISTIC MISSILESBy their bright exhaust plumes and uniqueflight profiles, flight tests of missile systems willcontinue to be easily monitored remotely. Staticground tests might also be visible. Static tests ofindividual missile stages and flight-tests at reducedrange can partially disguise capabilitiesand make it difficult in the early stages of aprogram to determine its intent. But the step-wiseprogress and extensive test programs required todevelop long range systems provide a lengthywindow for observation.MISSILE DEPLOYMENTIf a country wanted to convince its neighborsthat it was indeed pursuing space-launch capabilitiesand not developing ballistic missiles, it mightsuggest that other countries inspect its missileproduction facilities. A plant that had the manufacturingcapacity to turn out only one or twoboosters per year would be less likely to be usedfor offensive missile production than one capableof mass-producing boosters by the dozen. Such acountry might also allow others to inspect itspayloads or observe its space launches at closerange. However, not all countries would allowsuch transparency in their space-launch programs.Furthermore, such inspections could onlyverify that a given production facility, launch, orseries of launches had a nonthreatening objective;they could not prove that the capability fordeveloping a ballistic-missile delivery systemwas absent.Like other delivery systems and weapons ofmass destruction themselves, monitoring ballisticmissiles can be more problematic once they aredeployed than during their development andproduction. The best opportunity for monitoring79 see David Ottaway, ‘‘Saudis Hid Acquisition of Missiles, ” Washington Post, March 29, 1988, p. A13; and Jim_ “U.S. CaughtNapping by Sine-Saudi Missile Deal,” Los Angeles Times, May 4, 1988.~ CaI-U5, Ballistic Missiles in Modern Conflict, op. cit., footnote 37, P. 62.81 S@o~, Assessing Ballistic Missile Proliferation, op. cit., fOOt120te 4, P. 6.82 For Cxmple, tie one-s~ge Chinese DF-3A missile (range of about 3,000 km with a 1,100-kg payload) weighs 65,000 kg; tie U.S. M.XICBM (1 1,000 km with 3,800 kg) weighs 90,000 kg. See, for example, The Militay Balance 1988-Z989, (lmndon: International Institute forStrategic Studies, 1988).

Chapter 5-The Proliferation of Delivery Systems I 235the status of missile programs (other than openlydisplayed space-launch systems) is clearly affordedby the development and testing phase.| Summary—Ballistic Missile ProliferationAccording to published sources, ballistic missileswith ranges from 300 to 600 km are alreadypossessed or being developed by well over adozen countries outside of the five declarednuclear powers. Their spread was greatly facilitatedby the export in the 1970s and 1980s ofScud-B missiles from the Soviet Union. With theadvent of the MTCR and an increasing number ofcountries abiding by its constraints on missiletrade, the potential number of non-Third Worldsuppliers of missiles has declined markedly.However, at the same time, additional countrieshave learned to copy, modify, extend the range of,and produce their own missiles, and a smallnumber have developed long range systems—often in conjunction with space-launch programsand foreign technical assistance.In general, the acquisition by developing countriesof more advanced missile technologiesthoseallowing ranges in excess of 1,000 km oraccuracies much better than roughly 0.3 per centof range-can be slowed but not stopped bymultilateral export controls. Those emergingmissile powers that might have the intent to strikeat the United States (e.g., Iran, Iraq, North Korea,Libya) will not be able to field long range missilesor ICBMs over the next 10 years, and those thatcould develop the capability (e.g., Israel, India,Taiwan) are not likely to have the intent. It istherefore unlikely that any country (other thanChina and the former Soviet republics thatalready possess intercontinental ballistic missilesor ICBMs) would pose a direct ballistic missilethreat to the United States within the next 10years.Nevertheless, given the continuing exportbehavior of North Korea and possibly China,the potential for collaboration between emergingmissile powers, and the possibility ofmissile experts becoming available from theformer Soviet Union or from financially troubledcompanies in other non-MTCR countries,expertise in both short-and long range missilesystems may continue to spread. Countries maycontinue to seek ballistic missiles for a number ofreasons, including their prestige, their psychologicalvalue as terror weapons, the opportunitiesthey provide for generating hard currency, technologytransfer from space-launch programs, oreven a shortage of trained pilots and infrastructureto support an air force. These motivations, combinedwith the fact that designing and manufacturingballistic missiles in general requires considerablyless sophistication than does producingjet engines for modem combat aircraft, willcontinue to make missile technology attractivefor a number of countries of proliferation concern.COMBAT AIRCRAFTThe potential use of combat aircraft for deliveringweapons of mass destruction poses a numberof complex issues. Advanced fighters and strikeaircraft can carry out a wide variety of missions—e.g., air defense, close air support of groundtroops, and striking targets inside enemy territory—and are widely accepted as legitimate militaryinstruments. 83 However, some also provide thecapability to deliver weapons of mass destruction,a mission not viewed with the same degree ofacceptance. It is difficult or impossible to allowthe former set of capabilities while preventing thelatter, since almost any combat aircraft with anattachment point for ordnance or for other equipmentcan be modified to accommodate anddeliver nonconventional weapons. Moreover, manypotential proliferant states either possess or canbuy combat aircraft far superior to availablemissiles in terms of payload, accuracy, range, andother characteristics. In most cases, the range,83 me I_J.N. Cwer exphcitly recognims the right of a nation to self-defense. Possession of combat aircraft fOr that purpose iS thus not illeg~under international law.

236 I Technologies Underlying Weapons of Mass Destructionaccuracy, and payload capabilities of combataircraft already possessed by developing countriesfar exceed those of’ their ballistic or cruisemissiles, and many more countries have aircraftthan have missiles. 84The relative numbers and capability of militaryaircraft in countries of proliferation concern varygreatly (see table 5-8). For example, the Israeli airforce, which includes 63 F-15, 209 F-16,95 KfirC2/C7, and 112 F-4E aircraft, 85 has a vastlygreater capability in wartime for large-scaleordnance delivery at long range, and in thepresence of hostile defenses, than is possessed bymost developing countries. For some countries,however, capability is determined more by theavailability of pilots, technicians, or even spareparts, than it is by numbers of aircraft. Thetraining given pilots and the doctrine they employis also very significant. Although variations inair-force size, readiness, and even pilot skillmight not matter much for delivering a singlenuclear weapon to an undefended target or a largecity, the overall capability of a proliferant’s airforce could affect its ability to deliver largequantities of chemical weapons by air, or toengage in a protracted conventional air war thatmight eventually escalate to use of weapons ofmass destruction.Outside NATO and the former Warsaw Pact,most nations with large air forces and advancedcombat aircraft also tend to have, or are thoughtto have, programs for the development of nuclear,chemical or biological weapons. 86 As can be seenfrom table 5-8, 7 of the top 10 non-NATOnonformer Soviet Bloc countries with the largestair forces are thought to have active programs inweapons of mass destruction (those not believedto have such programs are Japan, Sweden, andYugoslavia); of those with the top 25 air forces,11 have active programs and another four arethought to have had programs in the 1980s that arenow being reversed. Furthermore, of all thedeveloping nations believed to be engaged in thedevelopment of weapons of mass destruction,only one, Myanmar (formerly Burma), has lessthan 150 combat aircraft. (Figure 5-4 illustratesthe overlapping nature of programs for thedevelopment of weapons of mass destruction invarious counties.)| Trade in Weapon-Capable AircraftThe proliferation of combat aircraft is alreadymore widespread and intractable than that ofballistic missiles. Although some dual-use technologiesuseful in the development of ballisticmissiles are still actively traded, trade in missilesthemselves has always caused concern and hasbeen subject to multilateral export controls sincethe MTCR was established in 1987. Nations areincreasingly willing to take diplomatic or economicmeasures to contain the spread of ballisticmissiles, forcing commerce in missiles-when ithas taken place-to be carried out clandestinely.In sharp contrast, most nations with advancedarms industries actively support the efforts oftheir aerospace companies to make internationalsales. The international market for fighters, interceptors,and strike aircraft is extremely competitive.In the middle 1980s, for example, when theU.S. Congress blocked the sale of F-15 fighteraircraft to Saudi Arabia, the Saudis turned to aU.K. firm, British Aerospace, and bought more84 ~S ~yS1s fwu5e5 on combat &raft in countries believed to have programs for developing Wewons Of ms des~ction (o~er *the five ackuowkdged nuclear powers in the case of nuclear weapons) or that have ballistic missile programs but are not full members of theMTCR. These countries are ahnost exclusively in the developing world. (See ch. 2 of U.S. Congress, Office of ‘Ikchnology AssessmentProliferation of Weapons of Mass Destruction: Assessing the Risks, op. cit., footnote 2, for the methodology used in identifyingmass-destmction weapon programs in these countries.)as ~tematio~ ~timte for Sti:~tegic Studies, The Military Balance 1992-1993 (Imdon: Massey’s, 1992).86 D~g tie ~HM over which most of tie aircraft diwuswd in this swtion were acquiret NATO and former Wmsaw Pact s~tes wmecovered by a nuclear umbrella and other security guarantees resulting from their NATO and Soviet Bloc alliances. The close ties these s~dteshad to superpower allies armed with weapons of mass destruction lessened their own motivations to develop such weapons.

Chapter 5-The Proliferation of Delivery Systems237Table 5-8-Combat Aircraft and Mass-Destruction Weapon Programs in Non-NATO andNon-former Warsaw Pact CountriesCountry a FGA b Fighter b Bomber Total b WMD/M c ExampleChina. . . . . . . . . . . . . . . 600North Korea. . . . . . . . . 346India. . . . . . . . . . . . . . . 400Israel. . . . . . . . . . . . . . . 169Syria. . . . . . . . . . . . . . . 170Taiwan. ... , . . . . . . . . , 512Japan. ........,.,.. 94-198Egypt. . . . . . ..,,.,.., 113-149Sweden . . . . . . . . . . . . . 97-237Yugoslavia . . . . . . . . . . 213-283South Korea. . . . . . . . . 265Libya, . . . . . . . . . . . . . . 128Pakistan . . . . . . . . . . . . . 126-150Iraq. . . . . . . . . . . . . . . . 130Saudi Arabia. . . . . . . . . 97-152Iran. ... , . . . . . . . . . . . 130South Africa . . . . . . . . . 116-245Algeria. . . . . . . . . . . . . . 57Afghanistan. . . . . . . . . . 110Switzerland. . . . . . . . . . 87Brazil. . . . . . . . . . . . . . . 200Singapore . . . . . . . . . . . 107-149Vietnam. . . . . . . . . . . . . 60Cuba. .......,. . . . . . 20Argentina . . . . . . . . . . . 16-894600376-387327479302-4630280295-323214126128238214180102-1321321418580-12313718381251406663081?900000000506000000000005830814?736648633512478472451409393371364316284262259242233224218187185160155(N)BCMNBCMNMNBCMBCMBCnoneCMnonenoneM?BCM[NBCM]MNBCM[N]M?N?M?Mnone[N]Mnonecnone[NM]Q-5(MiG-19)MiG-29Mirage-2000F-15/16MiG-29F-5F-15F-16JA-37MiG-29F-16Mirage F-lF-16MiG-29F-15C/DF-14Mirage F-lMiG-23MiG-23Mirage IllF-5F-16Su-17MiG-29SuperEntendardKey: FGA=fighter/ground-attack aircraftFighter -combat aircraft optimized for air-to-air missionBomber = aircraft optimized for delivering large payloads of bombs at relatively long range, possibly with internal bomb bay, and lackingair-combat capabilitya Countries with less than 150 combat aircraft are not listed. The only such cxruntry that is frequently reported to have a m~~struction wea~nprogram is Myanmar (Burma), which is suspected of having chemical warfare capability and is reported to have 12 fighter aircratt.b Higher numbers include combatepabte trainer aircraft, which are also inciudd in totals.c WMD/M . wea~n of mass destruction or missile program:N E frequently reported as having or trying to acquire nuclear weaponsB = frequently reported as having offensive biological warfare programC - frequently reported as having offensive chemical warfare capabilityM - suspected of having or developing ballistic missiles with range of at least 300 km, and not full member of the MTCR as of March 1993[ ] - Pro9ram in reVerSal or no longer considered a proliferant threatStates are listed here as having nuclear, chemical, and biolog’kal weapon programs if they are commonly citecf in the public literature as having suchprograms, as reviewed in ch. 2 of U.S. Congress, Office of Technology Assessment, Pro/iferafion of Wapons ofhfass Destruction: Assessing theRisks, OTA4SC-559 (Washington, DC: U.S. Government Printing Office, August 1993). See also figure 5-4, drawn from the same source. (SinceChina is a nuclear-weapon state under the Nuclear Non-Proliferation Treaty, it is not considered a “nuclear proliferant” here.) States are listed ashaving missiles if they are listed in table 5-3 as havhg indigenous missile programs or imported missiles.d Federal Republic of Yugoslavia (Serbia-Montenegro)SOURCE: Office of Technology Assessment. Based on information drawn from International Institute for strategic Studies, The Mi//!ary Balance1992-1993 (Imndon: International Institute for Strategic Studies, 1992).

238 I Technologies Underlying Weapons of Mass Destructions- ;c “p(a) Mirage-2000(b) Tornado(c) Kfir (d) F-16Advanced combat aircraft such as (a) the French Mirage-2000, (b) the Gerrnan/British/Italian Tornado, (c) theIsraeli Kfir, and (d) the U.S. F-16 are operated by a number of countries around the world, some of which arethought to have programs to develop weapons of mass destruction.Moreover, as developing nations have contin-ued to purchase advanced combat aircraft, theyhave increasingly demanded transfer or licensingof underlying production technologies as part ofthan 100 comparable Tornado IDS aircraft. 87 In afew instances, political or regional considerationshave made it difficult for countries to obtainadvanced combat aircraft, but most have beenable to do s0. 88ST The Tornado aircraft includes technology and components developed and manufactured in Brit@ Germany, and Italy. It haS comiderablyless air-combat capability than the F-15.88 For ex~p]e, IH@an F-14 ticrtit played only a small role in delivering conventional C)r@ce during the hn-hw Wm. lagely ~~usethe United States had cut off spare parts, training, and maintenance support following the Islamic revolution in 1979. On the other hand, evenunder the Pressler Amendment, which cut off aid (including military aid) to Pakistan after the President could no longer certify that it did notpossess a nuclear weapon, commercial sales of military equipment supporting that country’s air force appear to have continued. See, forexample, “Shipments to Pakistan Under Investigation,” Washington Post, Mar. 7, 1992, p. Al.

Chapter 5-The Proliferation of Delivery Systems | 239Figure 5-4-Suspected Weapon ofMass Destruction ProgramsThe General Dynamics F-16 fighter, here beingassembled at the U.S. Fort Worth facility, is flown by17 air forces around the world. Licensed coproductionfacilities have been built in Belgium,Turkey, and the Netherlands.the transaction. 89 These licensed production arrangementshelp build up and extend the defenseindustrial infrastructure of recipient nations. Suchtransfers are often accomplished through complicatedsales agreements, for example, in which therecipient nation buys a few copies of an advancedfighter off-the-shelf, assembles a second batchunder license, and-to the extent that its industrialbase can absorb and produce the technologiesand components in question—manufactures therest indigenously. In such transfers, highly sophisticatedand classified subsystems are oftenwithheld by the seller or provided in a downgradedversion as an assembled component.Over the past several years, trade in advancedcombat aircraft has been brisk. During 1987-1992, the 20 developing countries having thelargest air forces ordered a total of over 1,600aircraft (see table 5-9). Of those aircraft, over\Proliferantnuclearweaponprogram/Myanmar (Burma)VietnamAlgeria?IndiaPakistan1h\\ China 2 I 1\ /ChemicalBiologicalarsenalweapon(probable ordevelopmentpossible)‘(possible)Shaded area: also hasScud-type or longerrange ballistic missile1 Iraqi programs reversed W ‘.N.2 Chlm IS an aho~edged nuclear-weapon state.SOURCE: U.S. Congress, Office of Technology Assessment, Proliferationof Wbapons of Msss Destruction: Assessing the Risks, OTA-ISG559 (Wash., DC: U.S. Government Printing Office, August 1993), p. 66.two-thirds were ordered by proliferant nationsthat either now possess or are thought to bedeveloping weapons of mass destruction (WMD),or were thought to be developing them at the timeof the orders.As these data suggest, proliferation of WMDcapableaircraft is embedded in the economiccompetition among firms of several differentnations. The most common reasons cited inEurope and the United States to export advancedcombat aircraft are that foreign military sales arenecessary both to maintain existing productionfacilities and to fund R&D within the firm for89 On tie subject of liwmed production of major weapon systems, see U.S. Congress, Office of lkchnology Assessment.+ GZOtilA~ Tr~e,OTA-ISC-460 (WashingtorL DC: U.S. Government Printing Office, June 1991), pp. 6-9. Selected licensed production agreements in the 1980sinclude: U.S. F-16 fighter (to ‘Ihrkey and to South Korea); French—Gaman Alpha Jet (to Egypt); Brazilian EMB-312 llmmo trainer (to Egypt);Anglo-French Jaguar fighter (to India); Soviet MiG-27 fighter (to India); and U.S. F-5E Tiger-2 fighter (to Taiwan). Selected licensedproduction agreements in the 1970s included: French Mirage F- 1 fighter (to South Africa); Soviet MiG-21 fighter (to India); and Soviet MiG-19fighter (to North Korea). See, for example, SIPRI Yearbook (New York: Oxford University Press, various years).

240 I Technologies Underlying Weapons of Mass DestructionTable 5-9-Combat Aircraft Ordered 1987-1992 by Countries of Proliferation Concern aCountry a Total WMD/M b No. Type of Aircraft Supplier c YearChina 76 (N)BCM 122440SU-24 FencerSU-27 FlankerMiG-29USSR,,VB199019911991North Korea 195 NBCM 2025150India 40 NM 151510SU-25 FrogfootMiG-29MiG-21 MFMiG-29JaguarSea HarrierUSSR,,USSR11France/U.K.U.K.198719871988198819881989Israel 90 NBCM 530301510F-15D Eagle dF-16CF-16DF-1 5A EagleF-1 5A EagleUs.,,,,,,,,19881988198819901991Syria8+ BCM78SU-24 FencerMiG-25 FoxhoundUSSR,,19881989Taiwan250 BC34615060Kfir-C7Kfir-TC7F-1 6Mirage 2000-5IsraelIsraelUs.France1991199119921992Egypt123 CM4241201046F-16CF-16DF-1 6DMirage-2000L-39 Albatros dF-16CUs.,,,,FranceLibyaUs.198719871988198819801991South Korea357 M?244241224120209120F-4D PhantomF-1 6DF-4E PhantomRF-4C PhantomF-4E PhantomF/A-18 HornetHawk dRF-4C PhantomF-1 6CUs.t,,,#l,,,,U.K.Us.,,198719881988198819891989199019901991Libya15 BCM15Su-24 FencerUSSR1988Pakistan196 NM11756050F-1 6AF-7F-1 6AMirage-30Us.ChinaUs.Australia1988198919891990Iraq 52 [NBCM] 3616Mirage F-1 CMirage F-1 CFranceFrance19871989Saudi Arabia 176 M 12420601272Iran 1 30+ NBCM ?15?F-15C EagleHawk-200Hawk-1 00F-15D EagleF-15XPMiG-21 FEMB-312 Tucano dMiG-29Us.U.K.U.K.U.S.Us.E. GermanyEgyptUSSR19871988199019901992198819881990

Chapter 5-The Proliferation of Delivery Systems | 241Country a Total WMD/M b No. Type of Aircraft SuppIier c YearSouth Africa 7 [N]M? 7 PC-7 d Switzerland 1989Algeria ? N?M? ? MiG-29 USSR 1988Afghanistan o MBrazil 43 [N]M 11 S2F-1 Canada 198723 F-5E Tiger II Us. 19883 F-5F Tiger Il d Us. 19886 Mirage-3E France 1988Vietnam o cArgentina o [NM]a See notes to Table 5-8 for explanation of countries listed.b See key to Table 5-8.c Supplier ~untfles in italics are not the original producers of the aircraft.d TrainerSOURCE: Office of Technology Assessment. Based on information from S/PR/ Yearbooks, 1988-92 (New York, NY: Oxford University Press, variousyears) and selected newspaper reports.future production. Proponents of combat aircraftexports also assert that in the absence of exports,the balance-of-payments deficit would rise andtens of thousands of domestic aerospace workerswould lose their jobs. Incentives for former Sovietrepublics to export military hardware, in the faceof severe economic hardship and shortages ofhard currency, are even stronger.In addition to reasons of economics andalliance politics, however, trade in combat aircraftis driven by their utility in a wide range ofmilitary roles, including air defense, close-airsupport, reconnaissance, antiship, and tacticalmissions. Arms exporters assert that friendlystates require combat aircraft to defend themselves.Such trade is also facilitated by the lack ofany legal restrictions. Since military aerospace isa multibillion dollar sector in international trade,it will be extremely difficult to slow proliferationof combat aircraft. Establishing meaningful limitswould require that major exporting nations adopta strict multilateral control regime that did notrecognize the right of participating nations tomake unilateral sales or transfer production technology.Given these economic, political, andmilitary realities, most analysts believe that aregime significantly curtailing trade in aircraft isunlikely to develop anytime soon. 90| Capabilities of Aircraft for DeliveringWeapons of Mass DestructionExisting aircraft inventories in both advancedand developing nations, and the diffusion ofproduction capacity, indicate that most countriespursuing weapons of mass destruction alreadyhave relatively modem combat aircraft capableaftersuitable modification-of delivering them toa variety of targets. While these states may be lessable to carry out sustained conventional aircombat, their current aircraft inventories areprobably able to deliver weapons of mass destruction,with the possible exceptions of large-scalechemical weapon delivery (which would requirea large number of missions) or penetrating themost heavily defended targets. Table 5-10 illustratessome of the capabilities of combat aircraftthat have been exported to or are currentlypossessed by proliferant states.In considering the requirements for effectivedelivery of multiple strikes (e.g., for waging~ Nevertheless, antagonistic nations or alliances of nations could eventually agree among themselves to reduce inventories of com~taircraft, as was done through the Conventional Armed Forces in Europe (CFE) Treaty.

242 Technologies Underlying Weapons of Mass DestructionTable 5-10-Capabilities of Selected Combat AircraftAircraft designation Payload [kg] Combat Radius~ [km] Generation b Speed cand country of originBrazilT-27500 460 (est.) 3.5 lowChinaJ-8 (Soviet derivative)J-7 (MiG-21 derivative)J-6 (MiG-19 derivative)J-5 (MiG-17 derivative)H-5 (II-28 derivative)H-6 (Tu-16 derivative)Q-5 (MiG-19 derivative)300?300500200 (est.)1,0003,0009,0001,000400 (est.)350 (est.)250 (est.)600 (est.)275 (est.)1,200 (est.)600221.51111.5highhighreed-himediummediummediumhighFranceMirage-2000Mirage F-1Mirage-5Mirage IllSuper Etendard1,0003,5005009079071,500370 (est.)4251,3901,3001,200850 (est.)432.523highhighhighhighhighFrance/GermanyAlpha Jet1,100 1,0752.5mediumFrance/U.K. Jaguar4,000 1,4083highIndiaAjeet (British Gnat derivative)IsraelKfir C2/C7DaggerSouth AfricaImpala I/n (Italian AermacchiMB-326 derivative)ChettahTaiwanAT-31,000 204 2 medium1,200 1,186(see French Mirage-5)1,800 13090 648(see French Mirage-5)3 high2.5 low1,900 900 (est.) 2.5 mediumU.K.BuccaneerSea Harrier3,000 9001,000 37023mediummediumU.K./Germany/ItalyTornado IDSUs.F-16 FalconF-15 EagleF-1 4 TomcatF-4 PhantomF-5 TigerF-104 StarfighterA-4 Skyhawk6,500 1,390 4 high1,400 1,20011,000 1,270 (F-15E)5,000 805 (est.)7,250 1,100730 8901,500 312 (est.)4,600 600 (est.)44432.522highhighhighhighhighhighmedium

—Chapter 5-The Proliferation of Delivery Systems 243Aircraft designationand country of origin Payload [kg] Combat Radius 8 [km] Generatlon b Speed cUSSRMiG-29 FulcrumMiG-27 Flogger DMiG-23 FloggerMiG-21 Fishbed1,4001,0002,0002,000500475370700 (est.)7007404332highhighhighhighSU-25 FrogfootSU-24 FencerSu-1 7/20/22SU-7 FitterTu-22/26 BlinderTu-16 Badger4,4003,0001,0001,00012,0003,790250 (est.)1,050630300 (est.)4,0003,1003.532.5231mediumhighhighmediumhighmediuma A=um~ un-refueled high-low-high flight profile carrying specified payload. However, Since fuel, payload, range, and SPeed can be trad~ againstone another, range and payload figures are subject to considerable variability.b Generation designates th e following approximate levels of te~hnolqy: 1- 1950s; 2- l~os; 3- 1970S; 4- 1980S. U.S. aircraft of the mid-1970s,however, receive a rating of generation 4.Speed low- subsonic, generally propeller driven; medium - near transonic, to barely supersonic in ideal conditions; high - supersonic capability,e.g., roughly Mach 1.2 and abovecSOURCE: Office of Technology Assessment. Based, in part, on information drawn from Jane’s A// fhe Workf’s Aircratt, 1978-1991 (Surrey, U. K.:Jane’s Information Group Limited, various years).large-scale chemical warfare), however, additionalfactors must be taken into account. First, asignificant number of aircraft possessed by mostdeveloping countries would probably not becombat-ready. Some may have been disassembledto supply spare parts. Others may be inwarehouses or in need of repair, and some willlikely have crashed,Second, combat aircraft vary widely in performanceand quality in terms of such factors asreliability, serviceability, logistics, pilot ergonomics,thrust-to-weight ratio, turning radius andtransient maneuver performance, and electroniccountermeasures, Quality factors could affect theability of aircraft to carry out certain types ofmissions, especially when facing opposing fighterinterceptorsor other significant air defenses. 91Moreover, as was demonstrated in Iraq, a superiorair power might quickly become involved andeffectively suppress even one of the larger airforces deployed in the developing world.Third, few developing countries have expertisein mission planning, rapid turn-around, or accurateweapon delivery. Many developing countrieswould have difficulty maintaining a skilled coreof pilots who are both able and willing to flymissions to deliver weapons of mass destruction.Capabilities for aircraft delivery of weapons atranges more than 1,000 to 2,000 km are also verylimited outside the major industrial powers. Longrange delivery might be facilitated by long rangebombers, aerial refueling, aircraft carriers, orforward bases. But few proliferant countries, ifany, are expected to be able to incorporate thesetechnologies into their air forces anytime soon.In sum, any of the countries listed in table 5-8could probably use their air forces to deliver atleast a single nuclear weapon (if they possessedone) in a regional context, at ranges between 500and 1,500 km, and under a wide variety ofconditions. Many could mount a small-scale, butnevertheless effective biological or perhaps even91 M defe~ capability can also be supplied by other countries. For example, the United States supplied Israel with AWACS covemge ~dthe Pah-iot system during the Persizm Gulf War.

244 I Technologies Underlying Weapons of Mass Destructiona chemical strike. 92 If additional nations embarkon programs for the development of weapons ofmass destruction, it is likely that many of themwould already have the capability to deliver suchweapons using aircraft. Nevertheless, the abilityof several of these countries’ air forces—likethose of existing proliferants-may be questionablein terms of conducting sustained warfare,delivering large quantities of chemical weapons,or maintaining an attack in the event of third-partyintervention.| Summary–Proliferation of WMD-CapableAircraftCombat aircraft with the range and payloadsufficient to deliver nuclear, chemical, and biologicalweapons, though possibly requiring somemodification, are possessed by almost all countriesof proliferation concern. In terms of payloadsdeliverable at specified ranges, the capabilities ofair forces of virtually all of these countries farsurpass those of their missiles. Furthermore, thereare no internationally binding restrictions onaircraft trade, which, in many cases, continues tobe motivated by economic and foreign policyconcerns.Although the complex set of required technologiesand expertise make it extremely difficult forcountries of proliferation concern to design andmanufacture advanced aircraft without externalassistance, licensed production arrangements haveincreasingly spread manufacturing technologiesto many parts of the world. Licensed coproductionor assembly of Western or formerSoviet supersonic aircraft is taking place inChina, India, Israel, South Africa, South Korea,and Taiwan. Developing countries that havemanufactured components or complete subsonicaircraft with some ground-attack capability includeArgentina, Brazil, Chile, and an Arabconsortium based in Egypt with the participationof Saudi Arabia, Qatar, and the United ArabEmirates. 93Because aircraft and missiles have differentrelative strengths-particularly in their ability topenetrate defenses—the two systems are not fullyinterchangeable. 94 Piloted aircraft have significantadvantages over other delivery systems interms of range, payload, accuracy, reliability,damage-assessment capability, and dispersal ofchemical or biological agents. They can be usedeffectively under most circumstances, usuallyeven in the presence of significant air defenses .95On the other hand, the unit price of a ballistic orcruise missile is considerably less than that of apiloted airplane, and missile delivery offers bothmilitary and psychological advantages, especiallyfor a country wishing to deliver a single nuclearweapon to a heavily defended area.CRUISE MISSILES AND UNMANNEDAERIAL VEHICLESThe Intermediate Range Nuclear Forces (INF)Treaty defines a cruise missile as “an unmanned,self-propelled vehicle that sustains flight throughthe use of aerodynamic lift over most of its flightpath,’ and that is intended as a ‘‘weapondelivery”vehicle. Very short range cruise missilescan be rocket-powered, but longer rangeones generally use small jet engines. Unmannedaerial vehicles (UAV) are usually slower movingair-breathing platforms (e.g., using jet or propel-9Z Mk of sp~ pws can degrade air-force combat readiness, but such degra&tion would not be as important for scenarios involvingdelivery of a very small number of nuclear or biological weapons.93 S=, for ~~ple, MarkL.amb~ ed.,.lune’sA//the World’ sAircraji: 1990-1991 (Sumey, U.K.: Jane’ sInformation Group Limited, 1990);and James G. Roche, Northrop Corp., ‘‘Tactical Aircraft, Ballistic and Cruise Missile Proliferation in the Developing World, ” paper presentedat the US conference Advanced< Weaponty in the Developing World, WashingtorL DC, June 12, 1992.94 See John R. Harvey, “Regicml Ballistic Missiles and Advanced Strike Aircraft: Comparing Military Effectiveness,” InternationalSecurity, vol. 17, No. 2., Fall 1992, pp. 41-83.95 For a more de~ed tiysis of air defense, see Arthur Charo, Continental Air Defense: A Neglected Dimension of Strategic Defense(Cambridge, MA: Center for Science and International Affairs, Harvard University, 1990).

Chapter 5-The Proliferation of Delivery Systems 1245ler engines) that are associated with reconnaissance,surveillance, target, or harassment missionsrather than weapon delivery. (Any aircraftcan theoretically be made into a UAV by incorporatingan autopilot, but the term usually refers tosystems initially designed for unmanned operation.)Both cruise missiles and UAVs are treatedhere as having potential for delivering weapons ofmass destruction. Although cruise-missile payloadsare generally less than those of ballisticmissiles and much less than aircraft, the ability ofsome modern cruise missiles to fly at very lowaltitudes and slow speeds makes them particularlywell suited for delivering chemical andbiological weapons.| Indigenous DevelopmentIn the past, indigenous development of guidanceand propulsion systems for long range cruisemissiles presented almost insurmountable barriersfor developing countries, In recent years,however, near-revolutionary advances in satellitenavigation, long-distance communications, compositematerials, and light-weight turbojet andturbofan engines have greatly facilitated cruisemissiledevelopment in a growing number ofcountries. Developing sophisticated, light-weightjet-engine technology remains a significant obstaclefor most Third World countries, Nevertheless,crude pulse-jet technology was successfully employedby the Germans in the V-1 “BuzzBomb”as early as World War II, achieving ranges andpayloads comparable to the V-2 and Scud missiles.96 Furthermore, although the MTCR guidelineshave restricted export since 1987 of completesystems and dedicated components forsystems exceeding the 300 km/500 kg threshold,relatively sophisticated ready-made componentsfrom (unrestricted) short range antiship cruisemissiles (ASCMs) and UAVs have been readilyavailable for some time. 97 Trade in thesecomponents-m any of which have civilian utility—is making the manufacture of longer rangesystems considerably easier than in the past.Indigenous cruise-missile design and productionhas therefore become far more difficult to control.Moreover, cruise missiles and UAVs can be muchsmaller than other aircraft, and many of them canfly at low altitudes and evade radar, thus makingthem exceedingly difficult to detect.As of the beginning of 1993, there were only 11known cruise missile systems in service thatexceeded the 1987 threshold of 300 km/500 kg,three in the United States and eight in Russia. 98The U.S. Air Launched Cruise Missile (ALCM),Tomahawk, and Advanced Cruise Missile (ACM)have ranges of 2,500 to 3,000 km when nucleararmedand over 1,000 km when armed with aconventional payload of 450 kg. Some Russiancruise missiles have 400 to 600-km ranges with1,000-kg payload; others have about 3,000 kmrange with 300-kg payload. China and India arebelieved to have active development programs forcruise missile with ranges of about 600 km, butunknown payloads.A growing number of countries already havedevelopment programs or the ability to manufacturecruise missiles with shorter range than thosedescribed above. The five acknowledged nuclearpowers have all designed and built advancedjet-powered missiles capable of being furtherdeveloped to give ranges in excess of 300 km atsupersonic speeds. Israel, Italy, Japan, Sweden,and Taiwan have all developed subsonic turbojet-96 See ~~ony L. uy, BUZZ Bomb (Boylston, MA: Monogram Aviation Publications, 1977).97 me new MTm @del~es adopted on J~uary 7, 1993 prohibit the transfer of any ballistic or cruke missik with r~ge over 3~ ~,regardless of payload, and any such missiles+egardless of range or payload-if the supplier has reason to believe they may be destined tocarry weapons of mass destruction. This would presumably restrict sales by MTCR members of any cruise missiles to suspected proliferantcountries (see figure 5-4).98 Data in ~s md the following paragraph is from Duncan Lennox, ‘‘Missile Race Continues, ’ Jane’s Dqfence Weekly, Jan. 23, 1993, p.20.

246 I Technologies Underlying Weapons of Mass Destructionpowered missiles capable of flying well beyond300 km. Brazil, Germany, Iraq, and North Koreaalso appear to have potential cruise missileprograms developing a variety of systems, mostof shorter range. In addition, Russia exhibitedseveral cruise missile designs in 1992 that couldbe developed for export, or even remanufacturedby other countries to begin programs of theirown. 99GUIDANCE SYSTEMSCommand guidanceShort range, radio-controlled command guidancesystems are relatively simple to design. TheSoviets have used command guidance fromairplanes, and the United States has developedseveral such systems. (The Germans also experimentedwith radio-controlled command guidancein the V-2 ballistic missile.) Several short rangeASCMs have also been equipped with TV terminalguidance. Such systems include Israel’sGabriel II, Taiwan’s version of the same, calledthe Hsiung Feng I, and the U.S. Standoff LandAttack Missile (SLAM). However, the range of acommand-guided system. is limited by that of thecommunication link. If a radio link is used, it issusceptible to jamming. And while launch fromaircraft can extend the effective range of commandguidedmissiles, an escort aircraft must thenremain within communication range of the missile.Inertial guidanceInertial guidance systems are one of the mostmature navigation technologies used in ballisticand cruise missiles. They use gyroscopes andaccelerometers to determine the missile’s orientationand its motion along a particular heading. Allgyroscopes are subject to drift error, however,which accumulates guidance inaccuracy overtime. Standard high-quality commercial aircraftsystems, for example, have errors leading to CEPson the order of 2 km per hour of flight. l00 (TheMTCR prohibits exporting cruise-missile navigationsystems that have accuracies better than 10km on a 300-km course, unless part of mannedaircraft.) To compensate for the drift error,systems can utilize externally supplied informationto update inertial navigation systems.TERCOMSince the 1970s, the United States has beenusing an advanced guidance system known asTERCOM (Terrain Contour Matching) for guidanceof long range cruise missiles. It operates bycomparing the altitude profile of the ground underportions of the missile’s flight path with terrainmaps stored in its computer database. TER-COM’s guidance computer makes course correctionsbased on differences between measured andexpected altitude data. Between updates, themissile’s flight is usually controlled by an inertialguidance system. l0l However, since TERCOMrelies on terrain variation, it is useless forguidance over water, and ill-suited to flat plainsor deserts. Furthermore, because TERCOM requiresaccurate pre-determined terrain mapsalong the approach to a target-usually requiringadvanced satellite techniques to produce—99 fiid., pp. 19, 21. Note hat IJ.N. StXUI@ Council Resolution 687 prohibits IracI from mfi@g or developing missfies with r~esexceeding 150 km.’00 See, for example, ‘‘Sagem !Mfting to Systems Integration to Expand Role as Avionics Supplier,’ Aviation Week & Space Technology,May 11, 1992, p. 50. Ring-laser and fiber-optic gyroscopes (the latter still under development) are capable of substantially greater accuracy,but their manufacture is limited to countries with the most advanced electronics industries.Iol Dews of the TERCOM system are given in John Toomay, ‘“lkchrdcal characteristics, ‘‘ in Richard Betts, cd., Cruise Missiles:Technology, Strategy, Polirics (Washingto~ DC: The Brookings Institution, 1981), pp. 36-9. Conventionally-armed versions of the U.S. cruisemissiles have a supplementary terminal guidance system known as Digital Scene Matching Area Correlation (DSMAC), which compares avisual image of the target with onc stored in the missile’s computer memory.

Chapter 5-The Proliferation of Delivery System | 247developing nations have had little means bywhich to exploit this technology. 102NAVSTAR Global Positioning SystemProvided a target’s coordinates are known inadvance, cruise missiles could use satellite navigationsuch as GPS (see box 5-C) to fly to a targetby any route desired. Circuitous routes using aseries of waypoints might be chosen, for instance,to avoid heavily defended areas.Although the MTCR guidelines prohibit exportof any GPS receivers that operate above 18 kmaltitude and 515 rn/see, or those designed ormodified for use in ballistic missiles or cruisemissile with ranges beyond 300 km, many exportableGPS receivers would still be cruise-missilecapable. Moreover, export restrictions do notapply to GPS receivers for use in aircraft, and theelectronic circuitry required to process GPSsignals would not be difficult for many countriesto duplicate or otherwise obtain.A number of methods (e.g., differential GPS)have been developed to improve on the accuracyof the GPS signal available to civilian users, butthese methods would not be necessary for deliveringweapons of mass destruction. 103 For attackswith weapons of mass destruction against secondechelonforces massing behind front lines, oragainst ‘‘soft’ civilian targets or populationcenters, even the worst-case 100-m accuracyprovided by the degraded commercial signalwould be sufficient to result essentially in a directhit.,“The air- or ship-launched U.S. Harpoon antishipcruise missile was first produced in 1977 and has beensold to 19 U.S. allies including Egypt, Iran, Pakistan,South Korea, and Saudi Arabia.PROPULSION AND AIRFRAME TECHNOLOGYCruise-missile propulsion systems, like guidancesystems, are also much more widely availablethan in the past. Unlike combat aircraft,whose weight and expense mandates large reusableengines, cruise missiles can use much smallerturbojet or turbofan engines. Such engines arenow manufactured in over 20 countries. 104 DespiteRussia’s agreeing to abide by the MissileTechnology Control Regime, the former SovietUnion may be a particularly good source of thistechnology, since the republics have yet to setupcyJonEnm zmm102 )7ve~ ifhigh-quall~ Stereographic fiageS ~o~d ~ pwc~ed from commerci~ Satelfite photographic semic~ such as the French SPOTor U.S. La.ndsat, it is unlikely that sufficient altitude resolution could be obtained for use with TERCOM systems. At most this imagery mighthelp with terminal guidance if there were distinctive terrain features in the neighborhood of the target and if the cruise missile could be equippedwith a radar altimeter.IOJ The GPS signal available to commercial users, known as the “Course Acquisition (C/A)” code, contains errors that have beenintentionally introduced to degrade accuracy. Differential GPS uses a receiver whose location is accurately known to calculate these errors.This information can then be used to correct the positions of other receivers viewing the same GPS satellites. This method can be used to obtaindramatic improvements even relative to the accuracy available to military users, called the “P-code.” Lee Alexander, “Differential GPS inOperation Desert Storm, ” GPS World, vol. 3, No. 6, June 1992, p. 37. As suck it could be particularly usefut in aiming ballistic missiksaccurately toward their targets prior to launch if other methods of doing so were not available. Other techniques for improving on the C/A codehave also been developed.1~ See Mark kbert, cd., Jane’s All the World’s Aircrafi, 1990-91, op. cit., footnote 93. Although small Jet engines me kcoming morewidely available, they are not required; even old propeller-piston engines could be used in some applications.

248 I Technologies Underlying Weapons of Mass DestructionBox 5-C-Satellite Navigation Systems and GPSSpace-based navigation systems began their development in the United States and former Soviet Union inthe early 1970s, and for a variety of applications can now offer precise navigation services at low cost. The mostdeveloped system is the U.S. NAVSTAR Global Positioning System (GPS), which will soon provide accurateposition (latitude, longitude, and altitude)and velocity information to receivers anywhere in thewotid.lhefull GPSconstellation will include 21 satellites plus three spares, and is scheduled to be operational by 1995. 1Using four atomic clocks, each GPS satellite continuously broadcasts its position relative to the center of theEarth along with the precise time. Using this data a receiver can compute its distance from each of the GPSsatellites it can observe, and therefore its own position by triangulation. Receivers must have access to a minimumof three simultaneous satellite broadcasts to obtain latitude and longitude information; a fourth satellite is neededto add altitude information. 2 GPS offers the advantages of being unlimitedly range, cheaper than TERCOM, andmore accurate than inertial navigation systems by themselves (GPS would normally be combined with an inertialnavigation system). 3To deny use of GPS’s full capabilities to adversaries, GPS satellites broadcast two signals-one intendedfor use only by authorized U.S. military receivers, known as P-code (Precision Service), and the other for civilianusers, known as C/A-code (Coarse/Acquisition). P-code offers position information accurate to withinapproximately 10 to 15 meters. The accuracy of C/A-code varies depending on how the United States operatesthe system, but can be in the neighborhood of 30 to 40 meters. Since even 40 meter accuracy is more than theUnited States wants to provide adversaries during a crisis, the C/A signal can be degraded by a technique knownas “Selective Availability,” which introduces intentional errors into the code limiting it to 100-m accuracy. 4 Evenso, this would be sufficiently accurate for most purposes involving weapons of mass destruction.Since navigational data of the quality delivered by GPS has very high commercial value, an extensive marketin GPS receivers has grown to meet commercial demand. Off-the-shelf GPS receivers are available for less than1 AS of Deoember 1992, 19 satellites were deployed2 Artur Knoth, “GPSTechnology and ThlrdMAxid Missiles,” h?t6t?Mbn&i/D8bn~ ~edew, vol. 25, May 1W2,p. 413. One more satetlite signal is required than the number of coordinates sought, sinoe the receiver must alsooalcuiate and remove the effeots of Its own dook error.3 Forex~ple, the U.S. Defense Department which has developed and mdntalns GPS, Ail methe mtellitesystem to supplement missile guidance in the new U.S. Standoff Land Attack Missile (SLAM), a variant of theHarpoon anti-sh}pcruise missile, andlnplannedupgrades tothetand-attackversion of the Tomahawksea-launchedwise missiles. See Eric Arnett, “The Most Serious Challenge of the 1990s? Cruise Misstles in the DevelopingMhld,” in W. Thomas Wander and Eric Arnett eds., ?7w Pm/l~nNlon of Advati Waponry: 7iino/ogy,Mot/vatIons, and!?esponses (Washington, DC: Arnedoan Association for the Advancement of Sofence, 1992). TheFrenoh company Sagemvviiloffer aplug-inupgrade toltslnertlal nsndgation systems to provide navigational updatesfrom a 12-ohannel GPS moeiver. It will also offer the Integrated GPSAnertlat system for sale. See “Sagem Shiftingto Systems Integration to Expand Role as Avionlos Supplier:’ Atiatlon Mek & Spaoe Tbclmology, May 11,1992,p. 50; and Clifford Bed, “World In a Box: Air Navigation Leaps Fonnrard,” /ntematbna/Delbm?e Retiew, vol. 25, May1992, pp. 417-418.4 Note, however, that the quoted GPS aocurades pertain to the *% oonfidenoe level, m that 1OO-m“aocuracy” here could translate roughly into a 40 to 50-m CEP (50Y0 confidence level). Sources on emphtcal GPSsignal acouracy include Philip Klass, “lnmarsat Dedston Pushes GPS to Forefront of Civil Nav-Sat Field,” AviationMek & Space 7iino/ogy, Jan. 14, 1991, p. 34; Bruce D. Nordwall, “fllght Tests Highlight New GPS Uses,Emphasize Need for GPS/Glonass System:’ Aviation Weki!i Space Tsohnology, DeQ 2,1991, pp. 71-73; and PaulM. Eng, “Who Knows Where You Are? The Satellite Knows:’ Business Wek Feb. 10, 1992, pp. 120-121. Toprevent unauthorized aocesstothe P-code, the GPS system iscapabteof encrypting it produdng what IscalledtheY-code.

Chapter 5-The Proliferation of Delivery Systems | 249$500, and relatively expensive, multichannel sets that provide more frequent updates sell for less than $5,000. 5Receiver prices are likely to continue to drop.The U.S. Government recognizing the system’s civil application, has promised to provide the C/A-code signalfree of charge for a period of at least 10 years. Commercial users are also exerting considerable pressure on theU.S. Department of Defense to cease degrading the C/A signaI. This pressure is likely to mount, particularly if GPSis widely adopted for use in international air-traffic control. 6Two other systems may offer navigational data in the future that can supplement that provided by GPS. TheSoviet Union has begun to deploy a system somewhat comparable to GPS called Glonass (Global NavigationSatellite System), and the international satellite agency Inmarsat plans to add GPS-like signals to its thirdgeneration of satellites. 7 Combining data received from the three systems would allow increased accuracy andreliability y, including the capability for real-time verification of the integrity of individual satellite signals. 8The Glonass system, which would provide the same accuracy to all users, advertises plus-or-minus 17-maccuracy 50 per cent of the time, comparable to P-code GPS accuracy. 9 However, only about 8 of the first 32Glonass satellites deployed are still in operation, and given the political situation in Russia, the system’s fate isuncertain. l05 Inevensive singte-channei reodvers, more appropriate for boaters than for drtiaft, must swit*sequentially among four GPS satellites in order to compute position; muitiohannei reoeivers aiiow reoeption frommore than one sateiiiteat a time, which improves accuracy and update-speed. Receivers with 6 channeis are wideiyavaiiabie, and 12 channeis can aiso be obtained. See Gordon W@ “Navigation,” &fotorBoaflng & Sa”/ing, voi. 168,No. 4, October 1991, pp. 65-77; and Jeff Hum, GPS:A Guide to VwNexf Uf//lty(Sunnyvaie, CA: Trimbie Navigation,1989).G See phiiip J. Kiass, “FAA Steps Up Program to introduce GPS as instrument Approaoh AM,” Atiation ~e~& Space Twhnology, Aug. 17, 1992, p. 38.7 see, for exm~e, Kiass, ‘iinmarsat D~don. “ ““r op. dt., footnote 4, p. 34. One reason for inmarsat’sdedsion to provide sateiiite navigation is oonoern that the United States may not continue to provide GPS services.8 Simultaneous access to five broadcasting satellites is suffident to detect whether one of the satellites ismalfunctioning, but six signais are needed to identify which one is in error. When the GPS mnsteiiation is complete,however, there should be enough satellites at any time in one’s iine-of-sight that this shouid not present a problem.See Bruce D. Nordwaii, “Fiight Tests Highiight New GPS Uses, Emphasize Need for GPS/Glonass System,”Aviation VWek & Space TWmo/ogy, Dec. 2, 1991, p. 71.9 Artur Knoth, 4(GpS Tbchnoiogy and ~ird WWid Missiies,” Op. dt, fOOtnOte 2, P. 414.10 Kiass, “inmarsat Dedsion. . ,“, op, ~tm, footnote 4, p. 35.hundred kilometers. ASCMs are widely availableand, due to their short range, are generally exempteven from the new MTCR restrictions.Nevertheless, very small, lightweight, andfuel-efficient engines, which are particularly im-portant for longer range or stealthy cruise mis-siles, are still very difficult for proliferant coun-tries to acquire.an effective system of export controls. l05 Moreover,Ukraine, which holds a substantial fractionof the former Soviet Union’s military aerospaceindustry, l06 has not yet agreed to abide by MTCRconstraints, Antiship cruise missiles (ASCMs)purchased from Russia or elsewhere could alsoprovide a proliferant country with engines suitableto power its own airframes up to perhaps a fewIos See, for ex~ple, William C. Potter, “Exports and Experts: Proliferation Risks from the New Commonweal@” Arms Control To&y,vol. 22, No. 1, July/August 1992, pp. 32-37; and Jeffrey M, LenoroviW “RussiarI Engine Firms Strive to Realign, ’ Aviation Week & SpaceTechnology, March 30, 1992, pp. 38-9.106 See, for exmple, Cen-1 Intelligence Agency, Dirmtomte of ~te~gence, “The Defense Industries of the Newly Independent States ofEurasiq ” OSE 93-10001, January 1993, p. 7.

250 I Technologies Underlying Weapons of Mass DestructionAirframes are probably the easiest part ofcruise missiles to produce indigenously. Unlikecombat aircraft, cruise missiles need only flyonce, lessening the requirements for fatigueresistantmaterials. They are also smaller, mostlysubsonic, and need only accelerate modestly, thusavoiding the need for the type of high-strength orspecialized materials typically found in ballisticmissiles and reentry vehicles. l07 Unless highspeedmaneuvers are required, cruise missiles andUAVs can more easily use light-weight or evenradar-absorbent materials that would not ordinarilystand up to great aerodynamic stresses. 108 Andsince they require no cockpit or features to protecta pilot, they can be built much more cheaply andwith smaller radar cross-sections than can pilotedaircraft.In sum, any country that supports an aerospaceindustry or has a modest industrialinfrastructure should be able to integratecommercially available GPS receivers, turbojetengines taken from imported ASCMs, andindigenously built composite airframes to buildits own cruise missiles. If launched from mannedaircraft, the effective range of such cruise missilescould be increased substantially. Harder, though,would be to build cruise missiles with ranges farexceeding 300 km (carrying 500 to 1,000-kgpayloads) or long range cruise missiles withlow-observable (stealthy) technology.OPERATIONAL FACTORSTo remain undetected by air defenses, cruisemissiles can be made to fly at very low altitudes,exploiting the natural radar cover offered byreflections off trees, buildings, hills and otherfeatures of the terrain. l09 (Other techniques forincreasing the probability of penetrating defensesinclude stealth technologies, supersonic speeds,or high-altitude approaches that might be detectedbut not easily engaged by air defense systems.U.S. and Soviet systems have incorporated anumber of these techniques.) Low flight, however,increases the risks of crashing and sacrificesfuel efficiency. 110 Look-ahead radars and maneuverabilitycan lessen the risk of crashes, but theirweight will decrease a cruise missile’s range, andtheir signal may help defenses locate them. Thesealso require fairly sophisticated guidance andcontrol technologies.Early generation land-attack cruise missileswere particularly vulnerable to defenses, as demonstratedby the largely unsuccessful attempt byEgypt to use them against Israel in the YomKippur War of 1973. To saturate air defenses andincrease the probability of key weapons gettingthrough, a state may therefore wish to accompanya few cruise missiles carrying weapons of massdestruction with a large number of decoys. Butsuch tactics would only be needed when attackingdefended areas. The number of cruise missilesneeded for guaranteed penetration would thus behighly scenario-dependent. 111The GPS system was designed to operate withcompletely passive receivers, obviating the needto send any signal back to the satellites. Receiverscan therefore operate undetected. However, sinceGPS radio signals can be weak even comparedwith background noise levels, in theory they canIW TMS adv~@ge is less s~ientincrui~missiles designed forunderwaterlaunch from sub- es, because the stresses inherent in changingpressure environments during fli@t require stronger materials.10S sk Mictiel ~~ge, U~ann~Aircrafi, Brassey’s Air power, vo~u~ ~ @ndon: Bwsey’s Defense Publishem, 1988), p. 121.lw seew~~ E. D* HOWLPW Can an UnmannedAerial Vehicle Fly?, ~ Paper P-7680-RGS (Santa Monica, CA: RAND GraduateSchool, October, 1990).110 me fi-brm~g en~es ~s~ ~ most c~se ~ssiles ~ction more efflcien~y at tigher altitudes, where the less dense W Educes boththe drag on the airframe and the quantity of fuel necessary for efficient combustion.111 See, for e~ple, maro, Continental Air fle~ense, Op. Cit., foo~ote 95.

Chapter 5-The Proliferation of Delivery Systems I 251be jammed, at least for short periods of time. 112(Between GPS updates, or if jammed, a cruisemissile would have to fly using an inertialsystem.) Although all GPS satellites broadcast onthe same frequency, each Glonass satellite broadcastsat its own frequency, and Inmarsat satelliteswill provide still more frequencies, 113 thus makingit difficult to jam the entire future suite ofsatellite navigation signals. Furthermore, an incomingcruise missile must be detected ahead oftime in or der for jamming attempts to be activated.At least for short range missile guidance,fiber-optic technology may also take on anincreasing role in the future. The United Statesand Brazil have developed systems that connectantitank and antihelicopter missiles to controllersat distances up to 15 km. These systems usefiber-optic cables that spin off the end of a reelwhen the missile is launched. 114 Although opticcables can transmit signals over hundreds ofkilometers without serious distortion, in practicethese systems would probably be limited to about100 km or less. 115 A tsuch ranges, much simplercommand-guidance systems are also available.| Availability of Cruise Missiles and UAVsNo land attack cruise missiles are known tohave been exported by the principal exporters ofcruise missiles (the five acknowledged nuclearpowers and Italy), and there is little reason tobelieve that these will be exported in the future. ll6Furthermore, no potential proliferant state ispublicly known to have developed or acquiredcruise missiles for the purpose of deliveringweapons of mass destruction. Still, acquisition bysuch countries cannot be ruled out. Many of thecomponents and technologies for producingcruise missiles fall outside of MTCR constraints,or can be obtained by converting civil systems,cannibalizing readily available ASCMs, or purchasingcruise missiles from non-MTCR suppliers.ANTISHIP CRUISE MISSILESThe effectiveness of ASCMs frost gained notorietyin 1967, when Soviet-built Styx antishipmissiles launched by Egypt sank the Israelidestroyer Eilat. More recently, incidents involvingASCMs drew worldwide attention whenFrench-built Exocet missiles destroyed the HMSSheffield in the 1982 Falklands War and damagedthe USS Stark in 1987 in the Persian Gulf.Although only 11 countries have designed andproduced ASCMs indigenously, ASCMs can112 me ablll~ t. jm Gps ~i@~ is st~ he subj~t of some de~tc, D~tio~ ~te~ desi~~ to receive GPS signals from above maybe less susceptible to jammin g. Edward R. Harshberger, Long Range Conventional Missiles: Issues for Near-Term Development, RAND NoteN-3328-RGSD (Santa Monic& CA: RAND Graduate School, 1991), p. 105. Furthermore, the nature of the signals broadcast by GPS satellitesshould make it possible using special signal-processing techniques to distinguish even ve~ weak broadcasts ffom background noise or frompOWelfUl J“amming signals, making GPS “a very hardy system.” Jeff Hm GPS: A Guide to the Next Utility (Sunnyvale, CA: TrimbleNavigatio@ 1989), p. 8.113 philip K~s, ‘ ‘-satD~ision~shes GpS to Forefront of CivflNav-Sat Fiel~ AviatiOn week & Space Technology, J~~ 14,1991,p. 34.11.I ~eu.s, NaV ~ ~so exPfien~g ~~ ~-la~ched, fiber opti~y-~idedatiship cruise missiles. ‘ ‘U.S. Navy Tksts Fiber-@tic DataLinks for Air-Launched Weapons,” Aviation Week & Space Technology, June 12, 1989, pp. 275-8.115 Hu@es ~epramhtives ~~cat~ ~ a s~taent quoted in “U.S. Navy ‘I&ts Fiber-Optic Data. . .,” ibid., tit a l~km me is ‘e~ tielimit for these systems. See also Carl White, “Light Fantastic: Fiber Optics: The Core of High-’Ikch Prognuns,” Sea Power, vol. 34, Mar@1991, p. 28.116 w.se~ Cms, CmiSe MiSSile prol~era~on in t~c 1990s (was@o% DC: Center for S@ate@c ~d Internationtd StUdieS, 1992), p. 32.

252 I Technologies Underlying Weapons of Mass DestructionFirst produced around 1980, the Chinese Silkwormliquid-fueled rocket-powered antiship cruise missilehas been exported to Egypt, Iran, Iraq, and Pakistan,and is coproduced under license in North Korea.readily be purchased. 117 They have consequentlyproliferated even more widely than ballisticmissiles, with over 40 Third World countries nowoperating them. 118 Three :systems in Particularhave been widely exported: the Chinese Silkworm(95 km/510 kg); the Soviet Styx (80 km/500 kg);and the French Exocet (65 km/165 kg). Othersystems exported to Third World countries includethe British Sea Eagle, Israeli Gabriel I/II,Italian Otomat, and U.S. Harpoon (see table5-11 ). Of these, the Otomat and Harpoon have theA remotely piloted vehicle ready for testing at WhiteSands Missile Range, NM. This ground-controlledfixed wing vehicle with a cruising speed of 60 knots isdesigned to carry sensors. It is not a weapon systemand is not designed to penetrate defenses. However,similar vehicles might be adaptable for weaponpurposes, for example, for biological attacks againstundefended targets.longest ranges, at 180 km and 220 km, respectively,but still fall short of the MTCR threshold.Many ASCMs rely on active radar or infraredhoming devices for terminal guidance againstships on the open ocean, which stand out readilyfrom their surroundings. As such, ASCMs wouldnot be very useful for land attacks except againstdistinctive short range targets. To give ASCMs atrue land-attack capability, their homing systemswould have to be replaced or supplemented byanother type of guidance. ll9Nevertheless, most ASCMs also use a rudimentaryinertial-guidance system to navigate intothe vicinity of a target that would be transferableI IT The 11 coU~e5 wi~ indigenous cruise-missiles are the five declared nuclear powers phs GWDMUI y, Israe~ Italy, Japan, Norway, andSweden. Six other countries either currently manufacture ASCMS based on another country’s design or have their own systems underdevelopment: Brazil, Indi% Iraq, North Korea, South AfiicA and Taiwan. Cams, Cruise Missile Proliferation in the 1990s, ibid., pp. 34,126-133 (table B4); and Duncan Lennox and Arthur Rees, eds., Jane’ sAir-Luunched Weapons (Surrey, UK: Jane’s Information Group, 1990),Issues 8 and 9.118 caI-us, Cmise Missile Proliferation in the 1990s, op. cit., footnote 116, p. 34. Even though many ASCMS cost more ti a w~fiondollars apiece, there has been considerable interest among Third World countries in purchasing ASCMS.119 The I-Jnited Shtes developed the Standoff Land Attack Missile (SLAM) by replacing the seeker of the Harpoon ASCM witi a televisiontermirudguidance system. Other countries that would likely be able to replace a traditional ASCM seeker with TV guidance include Israel, IndkSouth Africa, Taiwaq and possibly South Korea. Carus, Cruise Missile Proliferation in the 1990s, op. cit., footnote 116, p. 131.

.Chapter 5-The Proliferation of Delivery Systems | 253Table 5-1 l—Selected Cruise Missiles and their CharacteristicsDesignation Range Payload Comment[km] [kg]ASCM Systems not exceeding the 1987 MTCR threshold of 300 k&500 kg:British Sea Eagle. . . . . . . . . . .Chinese HY-2. . . . . . . . . . . . . .(Soviet SS-N-2 derivative)Chinese HY-4. . . . . . . . . . . . . .French Exocet. . . . . . . . . . . . .German Kormoran 2. . . . . . . .Israeli Gabriel Mk-II. . . . . . . . .Israeli Gabriel Mk-lV. . . . . . . .Italian Otomat Mk-II. . . . . . . . .Japanese SSM-1. . . . . . . . . . .Norwegian Penguin Mk-III. . . .Soviet SS-N-2C. . . . . . . . . . . .Soviet AS-5. . . . . . . . . . . . . . . .Swedish RBS-15. . . . . . . . . . .Taiwanese Hsiung Feng-2. . .U.S. Harpoon. . . . . . . . . . . . . .110951356555+4020018015040+8023070-15080-180120-2202305105001652201801 50+210250120500100025075?2201985; turbojet; exported to Germany, India+1980; “Silkworm”; liquid-fuel rocket-powered; exported to Egypt,Iran, Iraq, Pakistan, and co-produced under license in DPRKlate 1980s; turbojet1979; solid-rocket powered; widely sold; operated by over 25countries1993; air-launched, rocket powered; operated only by Germany andItaly1976; solid-rocket powered; licensed variants produced in Taiwanand South Africa; exported to Chile, Ecuador, Kenya Singapore,Thailand1993?; turbojet (under development)Selected longer range cruise missiles (restricted from export by MTCR guidelines):1984; turbojet; European consortium; exported to Egypt, Iraq, Kenya,Libya, Nigeria, Peru, Saudi Arabia, and Venezuela1988; turbojet; land-, ship-, or submarine-launched1987; solid-rocket powered; exported to Greece, Turkey, Sweden,and United States1962; “Styx”; liquid-rocket powered; exported to Algeria, Angola,Cuba Egypt, Ethiopia, Finland, India, North Korea, Libya, Somalia,Syria, Vietnam, Yemen, Yugoslavia; licensed production in Iraq1966; liquid-rocket powered; “Kelt”; past exports to Egypt and Iraq;may exceed MTCR limits; land-attack and ASCM capability1989; turbojet; exported to Finland, and possibly to Yugoslavia1993?; turbofan?; (pre-production development)1977; turbojet; air- and sea-launch platforms; sold to 19 U.S. alliesincluding Egypt, Iran, Pakistan, South Korea, and Saudi Arabia;Iand-attack version (SLAM) has shorter range and television terminalguidanceSoviet SS-N-3. . . . . . . . . . . 460 1000 1963; turbojet; “Shaddock”; strategic/anti-ship; launched from land,surface ships, and surfaced submarines; sold to Syria and YugoslaviaSoviet AS-6. . . . . . . . . . . . . 560 1000 1973; solid-rocket powered; “Kingfish”; Mach 3.5; land-attack capability;can be nuclear-armedSoviet SS-N-21. . . . . . . . . 3000 300 1987; turbofan; “Sampson”; nuclear-armedU.S. Tomahawk. . . . . . . . . 480-1250 450 1983; turbofan; HE warhead; 2500-km range with 300-kg payloadU.S. ACM. . . . . . . . . . . . . . 3000 ? 1992; nuclear-armed; stealthy; air-launchedSOURCE: W.Seth Carus, Cruise Missile Proh’femtion in the 19WM (Washington, DC: Center for Strategic and International Studies, 1992); Jane’sA/rLaunched Weapons, Issue 09, and Jane’s Strategk Weapons Systems, Issue 07 (Surrey, U.K.: Jane’s Information Group Limited, 1992); andJames G. Roche, Northrop Corp., “Tactical Aircraft, Ballistic and Cruise Missile Proliferation in the Developing World, ” paper presented at the AAASconference Advanced Weaponry in the Developing World, Washington, DC, June 12, 1992.

254 I Technologies Underlying Weapons of Mass Destructionto other platforms and missions. Systems such asthe Israeli Gabriel II, which has been exported toseveral Third World countries (see table 5-1 1),use TV-terminal guidance and can therefore beused against land targets. Furthermore, typicalASCM payloads of 100 to 500 kg (sufficient formany types of high-explosive armor-piercingwarheads) would be sufficient to carry biologicalagents or modest amounts of chemical agent.Soviet export models and some ASCMs copiedby other countries have payloads of 500 to asmuch as 1,000 kg, which may be sufficient tocarry proliferant nuclear warheads. 120UNMANNED AERIAL VEHICLESAn alternative to developing or modifyingcruise missiles would be to purchase commerciallyavailable unmanned aerial vehicles (UAVs).Modern over-land UAVs are used in a widevariety of roles around the world, and could bepurchased under the guise of surveillance forfighting drug trafficking,, forest fires, or illegalimmigration. A state could then disassemble themfor parts or mod@ them for weapon-delivery .121UAVs or “target drones” could also be madefrom expendable auto-piloted aircraft programmedfor one-way missions.UAVs offer many of the characteristics ofcruise missiles. 122 However, most of them do nothave suitable payload or range to be useful forcarrying weapons of mass destruction. For instance,many are intended for short range reconnaissancemissions, carrying sensor-payloads of20 to 40 kg to ranges of less than 100 km. 123Others are designed as target or harassmentdrones or for long endurance flight, but withpayloads well under 100 kg. Nevertheless, longerrange systems able to carry several hundredkilograms to ranges of several hundred kilometershave been designed in recent years by a numberof companies. 124One example is the Teledyne-Ryan Model 350,built under contract in the United States as asurveillance platform. This UAV has a wingspanand length of only 3.2 m and 5 m, respectively,making it hard for enemy air defenses to detect . l25Its turbojet engine can achieve speeds of Mach 0.9and carry a 146-kg payload to a range of 1,500 kmand back. It is based on an earlier model (Model324, or “Scarab”) sold to the Egyptian armedforces in 1988 for reconnaissance purposes. 126Although the Scarab can carry 113 kg to a rangeof 1,000 km and back, it could not carry payloadsexceeding the 500 kg MTCR threshold withoutsubstantial redesign and in-field modification. ItsIn Bo~ tie Ufited Stites and tie former Soviet Union have produced nuc/ear-armed ASCMS for their own fkds, but each ~ nowcommitted to removing them.121 me most sucWss~ ~m~t use of UAVs by developing countries was in the 1982 Israeli action against Syrian fdr defenses k tie BekWiley in Ubanon. There, Israeli- ttnd U.S.-designed UAVS were used for both reconnaissance and harassment. UAVS caused Syrian SAMair-defense batteries to trigger their fire control radar, leaving the SAMS open to Israeli anti-radiation missiles without exposing Israeli aircraftto the air defenses. The Syrians lost 19 out of 20 SAM batteries and 86 combat aircraft while Israel lost one combat aircraft. Sir MichaelArmitage, Unmanned Aircraji, Bras.rey’s Air Power, Volume 3, op. cit., footnote 108, pp. 854.122 For x, in fact, some UAVS are speciflcal.ly designed to mimic the characteristics of cruise missiles. Don Flamm, “Defense‘Ikchnology: Unmann MI Aerial Vehicles,” Asian Defense Journal, Augus4 1991, p. 27.IZ see, for ~-pie, E.R. Hoot[In ~d Kenne~ Munso~ eds., Jane’s Battlefield Surveillance Systems, 3rd edition, ~99~-92 (SurreY, ~:Jane’s Information Group, 1991).IM Stefa&is@eyner, “Chumnt Developments in Unmanned Aerial Vehicles,’ ‘ArtiInternutional, vol. 14, October/November, 1990,pp. 78-80.1~ ~cti~ data for tie Model 350 is taken from Jane’ sBattl@ieid Surveillance Systems, op. cit., footnote 123, p. 229; ~d Gekenheyner,‘‘Current Developments in Unmanned Aerial Vehicles,” op. cit., footnote 124, pp. 80-3.lx me swab is btit almost en~ely of low rdw-cmw-Wtion Kwlw-e~xy composites and can be progrfimmtxl for long range @danceusing a satellite navigation system and up to 100 waypoints. Don Flamm, ‘Defense ‘lkd.nology: Unmann ed Aerial Vehicles,’ op. cit., footnote122, p. 28.

Chapter 5–The Proliferation of Delivery Systems | 255export to Egypt was only approved by the UnitedStates subject to a U.S.-Egypt bilateral agreementrestricting its use to reconnaissance within Egypt,forbidding modification, and giving the UnitedStates the right to inspect the inventory on shortnotice. 127Other examples of UAVs that could be givenground-attack capabilities include indigenouslyproduced target drones or small RPVs built byArgentina, India, Iran, and Iraq.128 Many of thesehave payloads well under 100 kg, however.| Monitoring Cruise Missile AcquisitionGiven the number of options available for theiracquisition, cruise missiles will be extremelydifficult to monitor in the developing world.Some cruise-missile related technologies-forexample, GPS receivers—have so many legitimateuses that commercial sales receive littlenotice. Even UAV systems that require exportnotification or licensing have both civilian andmilitary uses completely unrelated to the deliveryof weapons of mass destruction, and whosepromotion may well be in the interest of theexporting nation.Indigenous production or cannibalization ofASCMs to acquire cruise missiles would bedifficult to detect. 129 Although flight tests wouldcertainly be required, cruise missiles have fewreadily identifiable inflight observables; theyexpel only modest amounts of heat and remainwell within the atmosphere. Low-flying cruisemissiles are difficult to detect even in wartime,when airspace is carefully monitored, illustratingthe difficulty of detecting covert tests. Theproliferation of at least short range cruise missilescould therefore prove to be an intractable problemover the next decade or so. Fortunately, longerrange land-attack systems are not yet available toproliferant countries and are still amenable tosome measure of control through the MTCR.127 ~jor Paticlc lvfichclso~ Egypt country director, OffIce of the Secretary of DefeIISe, private cOmmunimtiOU Jme 2, 1993.‘~ Roche, “Tactical Aircraft. . .,” op. cit., footnote 93, p. 11.129 See, fo rexample, U.S. Congress, Office of Technology Assessment, A40niron”ng Limits on Sea-LuunchedCruise Missiles, OTA-ISC-5 13(Washington+ DC: U.S. Government Printing Office, September 1992), pp. 11,21.

IndexAccuracy of delivery systems, 211Acetylcholinesterasebiomarker technique, 68-69inhibition test, 61, 108ACM. See Advanced Cruise MissileActive monitoring, 65-68Ad Hoc Group of Government Experts, 75Advanced Cruise Missile, 245Aerodynamic enrichment processes, 6, 126, 178Aerosolsdescription, 33effect of particle size, 96physical stabilization, 96-97technical hurdles involved in BW dissemination, 95types of attacks, 97-99Air Launched Cruise Missile, 245Air-sampling systems, 65-66Aircraft. See Combat aircraftAirframe technology, 247, 249-250ALCM. See Air Launched Cruise MissileAlkylation, 26,27,44-45,56American Type Culture Collection, 84Anthrax, 78-79,84,88,92,93Antiagglomerants, 33Antiship cruise missilesavailability, 251-254propulsion technology, 249-250Antitactical ballistic missile systems, 231Area aerosol attacks, 97-98Argentina, 224-225Argonne National Laboratory, 159Arrow interceptors, 232Artillery shells, 34Asahi ion-exchange process, 178ASCMs. See Antiship cruise missilesATBMs. See Antitactical ballistic missile systemsATCC. See American Type Culture CollectionAtmospheric nuclear tests, 153Atomic Vapor Laser Isotope Separation, 178-179Australia Group, 29-31AVLIS. See Atomic Vapor Laser Isotope SeparationBacillus thuringiensis, 93-94, 102Bacteriadescription, 77-79production of bacterial agents, 87-89Ballistic missilesclassification, 207, 211controI systems, 228-230monitoring, 233-235obtaining technology, 217-228propulsion technologies, 213-217status of proliferation, 208-213summary, 235weaponization and deployment, 228-233Batch recycling, 177Bayer, 55Becker nozzle process, 146-149BIGEYE spray bomb, 34Binary CW agent production, 57-58Binary CW munitions, 34-35Bioassays, 61, 108Biochemical signatures for BTW agents, 106, 108-109Biological and toxin weaponsacquiring capability, 82-86agents for military use, 76-82implications of new technology, 10-11indicators of agent production, 99-113integration with delivery systems, 94-99large-scale production, 8-9,86-93military implications of genetic engineering, 113-117monitoring production, 9-10I 257

258 I Technologies Underlying Weapons of Mass Destructionoverview, 71-73stabilization of agents, 93-94summary, 73-76technical hurdles for program, 2-3Biological and Toxin Weapons Convention, 10,72,74-75Biomarkers, 50,68-69, 106Bioregulators, 116-117Biosafety Level, 91-92Biosensors, 61, 108BL. See Biosafety LevelBlack-market proliferation, 4Blood agents, 18Boosting, 175Botulinal toxin, 80Brookhaven Graphite Research Reactor, 156-157Brucellosis, 80,88BTW. See Biological and toxin weaponsBulk-handling facilities, 188BunkersBTW agent storage, 105, 107CW agent storage, 50-51Bursting CW munitions, 34Bush administration, 74-75BWC. See Biological and Toxin Weapons ConventionC/A-code. See Coarse/AcquisitionCalutrons, 144, 179Camouflage, concealment, and deception, 41, 44, 52-53,64-65, 102, 112-113, 168-169CANDU-type reactors, 188Carbamates, 28Carriers for CW agents, 32Cascades, 140, 145CBUs. See Cluster-bomb unitsCC&D. See Camouflage, concealment, and deceptionCenters for Disease Control, 107Centrifuge technology, 126, 177CEP. See Circular Error ProbableChemex process, 178Chemical additivesbiological and toxin agents, 93-94chemical weapon agents, 32-33Chemical exchange enrichment processes, 126, 178chemical Reaction by Isotopic Selective Activation, 178chemical warfare. See chemical weaponsChemical weapon signaturesbiomarkers, 68-69near-site monitoring techniques, 65-68onsite inspection techniques, 48-49, 60-65overview of techniques for detection and analysis, 59-60remote monitoring techniques, 65-68chemical weaponsacquisition, 18-21alternative proliferation pathways, 17-18,53-58chemical additives, 32-33clandestine production, 49-50cluster bombs, 35containment, 31-32filling operations, 33implications of new technology, 27-28indicators of proliferation activities, 16-17, 36-53missile delivery systems, 35-36monitoring proliferation, 7-8munitions design, 33-35nerve agents, 23-27overview, 15-16precursor chemicals, 28-31production, 6-7sulfur mustard, 21-23summary, 16-18technical hurdles for program, 2-3waste treatment, 31-32Chemical Weapons Convention, 15,28,37,59Chimaeric toxins, 116China, 218-219,232,252-253Choking agents, 18Circular Error Probable, 211Civilian nuclear research programs, 153. See also Nuclearfuel cycleClean rooms, 92cloning, 90Clostridium botulinum toxin, 80Cluster-bomb units, 98-99Cluster bombs, 35Cluster warheads, 36Coarse/Acquisition code, 248-249Combat aircraftin countries of proliferation concern, 235-237for delivering weapons of mass destruction, 241-244proliferations summary, 244trade in weapon-capable aircraft, 236, 238-241Command guidance, 246Commercial plant conversion to CW production, 54-57Computer simulation of nuclear weapons, 125, 150-152Concealment. See Camouflage, concealment, and deceptionCondor II program, 224-225CONSEN Group, 224Containment measuresbiological and toxic agents, 91-93, 104-106chemical weapon agents, 31-32Cooperative monitoring regime for CW, 37Corrosion-resistant materials, 26,4546Country tabulationsballistic missile production capabilities, 212ballistic missile programs, 208-210combat aircraft capabilities, 242-243combat aircraft inventories, 237combat aircraft orders, 240-241cruise missile and ASCM programs, 253enrichment capabilities, 148MTCR participants, 200nuclear reactors in, 182plutonium and uranium recycling policies, 141of proliferation concern, 239reprocessing capabilities, 139

Index I 259CRISLA. See Chemical Reaction by Isotopic SelectiveActivationCritical mass, 5, 173Criticality tests, 166Cruise missilesavailability, 251-254chemical weapon delivery system, 36defined, 244indigenous development, 245-251monitoring acquisition, 255Cuba, 107CW. See Chemical weaponsCWC. See Chemical Weapons ConventionCyanation, 25Deception strategies for CW production, 64-65Decoupled nuclear tests, 169-170Dedicated CW production facilities, 54Deep underground wells, 48Defectors, 38Defense Intelligence Agency, 114Defense penetration, 205-206Delivery systemsavailability, 199-200ballistic missiles, 207-235barriers to proliferation, 12chemical weapons, 35-36combat aircraft, 235-244cruise missiles, 244-255effectiveness, 198-199, 201-207monitoring, 12-13, 201, 233-234, 255overview, 11-12, 197-198signatures, 107, 201summary, 198-202technological barriers to proliferation, 200unmanned aerial vehicles, 244-255Designer decontamination, 64DIAL. See Differential absorption lidarDiatoms, 68Differential absorption lidar, 67Dimethyl methylphosphonate, 29,55, 62-64Distillation, 26Diversion of nuclear materials, 4, 130-131, 135, 183-190DMMP. See Dimethyl methylphosphonateDNA adducts, 69Dual-use export controls (nuclear)guidelines, 191-192items to be controlled, 192-194potential limitations of the guidelines, 195strengths of the guidelines, 194Dual-use materialsbiological and toxic agents, 84-86chemicals, 29Dusty mustard, 32Economic dislocations, 40Effluent analysis, 49Egypt, 224-225,254-255Electromagnetic isotope separators, 144Electromagnetic enrichment processes, 179-180Electron-capture detector, 61ELISA. See Enzyme-linked immunosorbent assayEMIS, See Electromagnetic isotope separatorsEnrichment technologiesaerodynamic processes, 126, 178chemical exchange processes, 126, 178description, 126-127, 140-149, 177-180electromagnetic processes, 179-180gas centrifuge, 126, 177gaseous diffusion, 126-127, 177implications of new technologies, 158laser processes, 126, 178-179properties of uranium, 176-177thermal diffusion, 177Enzyme-linked immunosorbent assay, 61Epidemic Intelligence Service, 107Epidemiological analysis, 110-113Explosive munitions for BTW delivery, 98Export controls. See Australia Group, Dual-use exportcontrolsExternal signaturesbiological and toxin weapons, 103-104chemical weapons, 38-44False positives, 62-64Filling operations, 33Finland, 59Fission devices, 173Flame photometric detector, 61Former Soviet Unionanthrax outbreak, 103biological weapon program, 72chemical weapon program, 21, 24, 27, 31-32, 35cruise missiles, 252-253Glonass, 200,249nuclear material leakage, 134-135potential diversion of nuclear weapons, 127-128signatures of biological warfare, 101use of U.S. nuclear design information, 154Fourier transform infrared spectroscopy, 67France, 132, 139-141, 151, 158-159, 178,222,248,251-253Freeze-drying, 93Freezing-point depressants, 32FTTR. See Fourier transform infrared spectroscopyFuel fraction, 227Fugitive emissions from CW plants, 65-66Fungi, 80Fusion weapons, 122, 175Fuzing, 161G-series nerve agents, 23-24GA. See TabunGas centrifuge technologies, 6, 177Gas chromatography/mass spectrometry, 60-62Gaseous diffusion technologies, 126-127, 177GB. See Sarin

260 I Technologies Underlying Weapons of Mass DestructionGC/MS. See Gas chromatography/mass spectrometryGD. See SomanGenetic analysis, 108Genetic engineeringincreasing controllability of microbial agents, 114-117modified toxins and bioregulators, 116-117possibility of novel BTW agents, 113-114Genetic fingerprinting, 109Germany, 24,25,219-222,229,245Global Navigation Satellite System, 200,251Global Positioning System, 167,200,229, 233,247-251Glonass. See Global Navigation Satellite SystemGPS, See Global Positioning SystemGuidance systems, 228-230,233,246Gun-type nuclear weapons, 166, 174H. See Sulfur mustardHanta virus, 111Hastelloy, 45HC1. See Hydrochloric acidHE testing. See High explosive testingHelikon process, 146-149HEU. See Highly enriched uraniumHF. See Hydrogen fluorideHigh explosive testing, 165-166High-performance liquid chromatography, 61Highly enriched uranium, 1351-136. See also UraniumHollow-fiber technology, 89-90HPLC. See High-performance liquid chromatographyHuman intelligencebiological and toxin weapons, 101chemical weapons, 38Hydrochloric acid, 25-26Hydrodynamic tests, 152Hydrogen fluoride, 25-26Hydronuclear tests, 152, 153IAEA. See International Atomic Energy AgencyICBMs. See Intercontinental ballistic missilesIdaho National Engineering Laboratory, 50IFR. See Integral fast reactorImhausen-Chemie, 42,43Immunological techniques, 108Implosion physics, 165-166Indiamissile expertise, 222unsafeguarded nuclear reactors, 157Inertial guidance, 246INF Treaty, See Intermediate Range Nuclear Forces TreatyINFCIRC/153 and /66 safeguards agreements, 183, 185Inmarsat, 249Integral fast reactor, 159-160Integrated Operational Nuclear Detection System, 167, 169Integrative monitoring, 65-68Intercontinental ballistic missiles, 207, 225-227Intermediate range ballistic missiles, 225-226Intermediate Range Nuclear Forces Treaty, 244Internal production signatures, 44-49International Atomic Energy Agencysafeguards, 4, 122-124, 184-190significant quantities of nuclear material, 174, 184Ion cyclotron resonance, 179-180Ion-exchange enrichment, 126, 142-143, 147-148, 178IONDS. See Integrated Operational Nuclear DetectionSystemIran-Iraq War. See Iraq, use of chemical weaponsIraqattempts to conceal nuclear signatures, 168-169back-integration, 31binary munitions, 35containment of biological weapons, 92cost of nuclear weapon research, 155missile programs, 220-221nuclear design efforts, 150-151sarin production, 26statements of nuclear intention, 165uranium production, 4use of chemical weapons, 15, 16, 21, 34IRBMs, See Intermediate range ballistic missilesIsrael, 157,252-253Italy, 252-253JapanAsahi ion-exchange process, 178biological weapon development in WW II, 88,92plutonium and uranium recycle policies, 141shipments of separated plutonium, 134Japan Steel Works, 42Karl Kolb firm, 47LAP. See Laser-Assisted ProcessesLaser-Assisted Processes, 178Laser-based sensing techniques, 67Laser isotope separation, 6, 126, 178-179Laser spectroscopy, 49, See also Remote spectroscopyLEU. See Low-enriched uraniumLibya, 42-44Lidar, 67Light-water reactors, 138, 159Liquid-fueled propulsion, 214-215Liquid-metal fast breeder reactors, 159LIS, See Laser isotope separationLMFBRs. See Liquid-metal fast breeder reactorsLong range missiles, 225-227Low-enriched uranium, 131LWRs. See Light-water reactorsLyophilization, 93Mass spectrometry, 60-61, 109Material accountancy, 162Material-unaccounted-for, 162Materials balance, 39Medium range ballistic missiles, 225-226Microbial agents, military implications, 114-116Microencapsulation, 94

——-——Index | 261Middle East, 218-219Missile delivery systems. See Ballistic missiles; Cruisemissiles, Delivery systemsMissile Technology Control Regime, 5, 11, 12, 199-200MLIS. See Molecular-vapor Laser Isotope SeparationMLRS. See Multiple Launch Rocket SystemModified toxins, 116Molecular-vapor Laser Isotope Separation, 142-143, 147-148, 178-179MRBMs. See Medium range ballistic missilesMTCR. See Missile Technology Control RegimeMUF. See Material-unaccounted-forMultiple Launch Rocket System, 34Multipurpose chemical plants, 56-57Munitionsbiological and toxic agents, 98-99chemical weapons agents, 33-35storage, 50-51Mustard gas. See Sulfur mustardMycotoxins, 81National Technical Means, 169Navigation systems, 228-230NAVSTAR. See Global Positioning SystemNDA. See Nondestructive assaysNDE. See Nondestructive evaluation methodsNear-site monitoring techniques, 49,65-68Nerve agentscosts of production, 27description, 18, 23-24production, 24-26technical hurdles, 26-27Neutron background measurements, 166-167Neutron initiators, 167NMR. See Nuclear magnetic resonance spectroscopyNNWS. See Non-nuclear-weapon state partiesNoble gases release, 164Non-nuclear-weapon state parties, 122Noncooperative monitoring regime for CW, 37Nondestructive assays of nuclear materials, 186Nondestructive evaluation methods of CW munitions, 50-51Nonprotein toxinsdescription, 81-82production of, 90-91North Koreadevelopment of production reactor, 157IAEA inspections, 186missile sales, 218Scud missiles, 220Noske-Haeser, 46Novel agents, 113-114NPT. See Nuclear Non-Proliferation TreatyNSG. See Nuclear Suppliers GroupNTM. See National Technical MeansNuclear fuel cyclecivilian nuclear research program, 153IAEA safeguards, 184-190number of installations under IAEA safeguards, 183power and research reactors around the world, 181, 182Nuclear magnetic resonance spectroscopy, 61Nuclear Non-Proliferation Treaty, 5, 122-124, 137, 185Nuclear Suppliers Group, 125, 191Nuclear testing, 122, 152-153, 167, 169-171Nuclear weapon proliferationacquiring nuclear weapon capability, 120, 127-130components and design of weapons, 173-175country-dependent factors, 119-120difficulty and detectability, 126-127effects of nuclear weapons, 175glossary of nuclear materials, 121implications of different technologies, 6international controls, 122-126, 191-195material production, 3-4monitoring, 5-6from nuclear materials to nuclear weapons, 149-161signatures of proliferation activities, 161-171sources of nuclear materials, 129-149stages involved in manufacturing nuclear weapons, 120,122technical barriers, 2-3, 5Onsite inspection techniques for CW, 60-65Optical detection systems for CW, 66-68P-code. See Precision ServicePakistan, 157PALS. See Permissive action linksPassive monitoring for CW, 65-68Patriot missiles, 231Payloadcapacities, 203-204, 208-210defined, 211PCR. See Polymerase chain reactionPenetrant chemicals, 28Permissive action links, 128Petrochemical-3, 168Phosphorus-methyl bond, 62Phosphorus oxychloride, 29Physical containment of BTW agents, 104-106PINS. See Portable Isotope Neutron SpectroscopyPlant conversion to CW production, 54-57Plant design for BTW production, 104Plasma centrifuge separation, 180Plutoniumestimated material conversion time for components, 185integral fast reactor fuel cycle, 159-160isotopic purification, 159liquid-metal fast breeder reactors, 159materials acquisition, 162, 163minimum-cost program, 156-158production, 3-4, 138reactor-grade, 131-132, 133recycling policies, 141reprocessing facilities, 138-140weapon-grade, 132, 134Point aerosol attacks for BTW, 98-99

262 I Technologies Underlying Weapons of Mass DestructionPollution-control equipment, 46-47Polymerase chain reaction, 108-109Portable Isotope Neutron Spectroscopy for CW detection,50-51Precision Service, 248Precursors, chemical weapons, 28-31Preparatory Commission for CWC, 59Pressurized BTW munitions, 98Production process equipment, chemical weapons, 44-45Production signaturesbiological and toxin weapons, 103-106, 112-113chemical weapons, 38-49, 52-53nuclear weapons, 162-164, 167Proliferation indicatorsbiological and toxin agents, 99-113chemical weapons, 16-17, 36-37CW weaponization and testing signatures, 51-53detecting clandestine CW production, 49-50external CW production signatures, 38-44internal CW production signatures, 44-49nuclear weapons, 161-171research and development signatures, 37-38storage of agents and munitions, 50-51Propulsion technologies, 213-217, 247,249-250Protein toxinsdescription, 80-81production of, 90-91Pugwash, 39Raman spectroscopy, 67Range of delivery systems, 2012-203,208-210,242-243, 253Raytheon Company, 231RBMK-type reactors, 188Reactor-grade plutonium, 131-132, 133Real-time monitoring for CW production, 65-68Reentry vehicles, 161,222-22,3,225Remote monitoring techniques for CW production, 65-68Remotely piloted vehicles, 36, 252,255Reprocessing, 131-133, 138-140, 164Research and developmentbiological and toxin weapon signatures, 100-101chemical weapons production, 37-38Restriction-fragment length polymorphism, 109Reverse engineering for ballistic missiles, 220RFLP. See Restriction-fragment length polymorphismRGPu. See Reactor-grade plutoniumRhodesia, 110Ricin, 80-81Rickettsiaedescription, 79production of, 89-90RPVs. See Remotely piloted vehiclesRussia. See Former Soviet UnionRV. See Reentry vehiclesSafeguards Implementation Report, 185Safety equipment for CW production, 46-47SAR. See Synthetic-aperture radarSarin, 25-26Saxitoxin, 81Scarab unmanned aerial vehicle, 254-255Scientific publications trackingbiological and toxin weapons, 100-101chemical weapon production, 37-38nuclear weapon design, 164-165Scud missilesexport of, 208-210, 212Iraq, 206,220-221Patriot defense, 231SEB. See Staphylococcus enterotoxin BSecond Review Conference for BWC, 74Seismic signature, 169-170Self reference, 262Separated plutoniumJapanese shipments, 134and reprocessing plants, 132, 134Separation factor, 140, 143, 176Separative work units, 141Short range ballistic missiles, 219-222,224-226Signatures, See Chemical signatures, Production signatures,Proliferation indicators, Seismic signatures, Testingsignatures, Visual signaturesSignificant quantities of nuclear material, 174, 184Silica gels, 68Single-purpose chemical plants, 55-56SIR. See Safeguards Implementation ReportSLAM. See Standoff Land Attack MissileSolid-fueled propulsion, 215-218Solvent-extraction enrichment process, 126, 178Soman, 25-26Sorbent materials, 68South Africa, 201-202South African Atomic Energy Corporation, 179Soviet Union. See Former Soviet UnionSpace-launch vehicles, 227-228Spent-fuel reprocessing. See ReprocessingSprays, 33SRBMs. See Short range ballistic missilesStabilizers, 32Stack emissions from CW plants, 65-66Staging for ballistic missiles, 226Standoff Land Attack Missile, 246Staphylococcus enterotoxin B, 80Storage bunkers. See BunkersSulfur mustarddusty mustard, 32production, 21-23SWUs. See Separative work unitsSynthetic-aperture radar, 41Tabun, 24-25Tactical ballistic missiles, 231Tamper, 173, 174Target drones, 254-255TBMs. See Tactical ballistic missilesTeledyne-Ryan Model 350,254

Index I 263TELs. See Transporter-erector-launchersTERCOM. See Terrain Contour MatchingTerrain Contour Matching, 246-247Testing signaturesbiological and toxin weapons, 102-103chemical munitions, 51-53nuclear weapons, 165-167, 169-171THAAD. See Theater high-altitude area defense interceptorTheater high-altitude area defense interceptor, 231-232Thermal diffusion, 177Thermonuclear weapons, 122, 175Thickeners, 32Thiodiglycol, 22-23Third Review Conference for the BWC, 74Threshold Test Ban Treaty, 153Tomahawk cruise missiles, 205Toxin agents. See Biological and toxin weapons, ToxinsToxinsanalysis, 109description, 80-82genetically engineered, 116production of, 90-91Transporter-erector-launchers, 230Treaty of Tlatelolco, 129Trichothecene mycotoxins, 81Tularemia, 77-78UAVs. See Unmanned aerial vehiclesU.N. Security Council Resolution 687, 151Underground nuclear tests, 170. See also Nuclear testingUnited Kingdombiological weapon activities, 88,98-99chemical weapon activities, 24delivery system activities, 252-253nucleari weapon material activities, 139-140United Statesbiological weapon activities, 73, 77,80,88,98-99, 101chemical weapon activities, 18, 21, 23, 24, 25, 26, 27, 34,35-36,57delivery system activities, 35-36, 98-99, 222, 231-232,252-253nuclear weapon or weapon material activities, 135,150-151, 170Unmanned aerial vehiclesavailability, 254-255description, 244-245indigenous development, 245-251Uraniumacquisition, 137-138costs for small-scale enrichment facility, 158enrichment technologies, 140-149, 177-180estimated material conversion time for components, 185implications of new enrichment technologies, 158materials acquisition signatures, 162-163production, 3-4properties of, 176-177recycling policies, 141special requirements for enrichment technologies, 147status of enrichment technologies by country, 148URENCO consortium, 141, 144U.S. Army MedicaI Research Institute of Chemical Defense,68U.S.-Japan Nuclear Cooperation Agreement, 134U.S.S.R. See Former Soviet UnionV-2 missile, 219-220,222V-series nerve agents, 24VEREX. See Verification experts group for the B WCVerification experts group for the BWC, 75Vesicants, See also Sulfur mustarddescription, 18Victor Meyer-Clarke Process, 22Virusesdescription, 79-80production of viral agents, 89-90Visual signaturesbiological and toxin weapons, 103-104chemical weapons production, 40-44nuclear weapon development, 166, 167, 169testing of chemical munitions, 51VX, 26Waste disposal, 47-48Waste lagoons, 47Waste treatment, 31-32Weapon-grade plutonium, 132, 134Weaponizationchemical weapons agents, 32-36delivery systems, 228-230nuclear devices, 160-161signatures, 51-53, 102-103World Health Organization, 110World War IIanthrax cluster bombs, 98-99pathogenic bacteria research, 88Yellowcake, 137Yellow rain, 81-82Zeolites, 68