Waste management: nuclear waste treatment ... - Sellafield Ltd

Waste management overviewWaste management:nuclear waste treatment,storage and disposalwww.nda.gov.uk | www.sellafieldsites.com | www.nuclearmanagementpartners.com

We deliver an integrated nuclear waste managementprogramme which seeks to reduce waste volumesarising as part of our current activities as well ashistoric operations, ensuring that waste is stored safely,minimising the risk to the public and environment.Nuclear waste treatmenWe are world leaders in nuclear waste management and havesuccessfully processed and stored low, intermediate and high levelnuclear waste from UK and overseas customers at our sites for over50 years.We have made major advances in the treatmentof these wastes over the past 30 years with thedevelopment and implementation of comprehensivewaste management processes and techniques.These include the development and introduction oftreatment for high level waste and encapsulationtechnology used to treat intermediate level waste.Significant progress has already been made with the retrievaland treatment of historic as well as current waste arisings. Futurechallenges in waste management lie in supporting the delivery ofhigh hazard reduction at Sellafield and Capenhurst and accelerationof this mission.Sellafield site.Our employees are worldleaders in nuclear wastemanagement.

We have 50 years experience in the treatment and storage of nuclear waste.t, storage and disposal

The greatest technical challenge we face isthe cost-effective retrieval and treatmentof the historic wastes at Sellafield.Challenge

Nuclear wastecategorisation.% High level waste1% Intermediate level waste1980% Combination of low levelwaste, very low level wasteand exempt wastesSuccessfully managingall types of nuclear wasteEarly waste management activities at Sellafieldinvolved the storage of untreated waste from thefirst generation reprocessing operations associatedwith the military programme which took place atSellafield during the 1950s. Waste arising from theprogramme was historically held in ponds and siloswith no plans for future treatment and disposal.Our task today is to retrieve and process thismaterial as well as manage the arisings producedfrom current reprocessing operations.With safety at the forefront of everything we do,our employees face some challenging but excitingtimes ahead. Representing some of the mostsignificant long term activities on the Sellafieldsite, our mission is to safely and efficientlymanage the disposition of waste toensure high hazard risk reduction. Wewill continue to develop innovativeand cost effective solutions to enableacceleration to this mission and indoing so, contribute towards a cleanerand safer environment.Tom Foster,NMP Executive Director for Sellafield Ltd,Waste and Effluent DispositionVery low level waste (VLLW)VLLW is radioactive waste with verylow concentrations of radioactivity.At Sellafield, this refers toradioactive waste which due to theconcentration levels in relation to itstotal activity can be disposed of tospecified landfill sites.High level waste (HLW)The most radioactive form of nuclearwaste and is produced when spentfuel has been reprocessed throughthe Magnox and Thorp facilities. AtSellafield, we treat this waste througha process called vitrification. Thisinvolves converting the high-levelliquid waste into a solid form,reducing the volume of the liquidwaste to one third of its originalsize. Vitrifying the waste enables thematerial to be stored safely and inpreparation for eventual transportand permanent long term storage.Intermediate level waste (ILW)Comprises of materials such as fuelelement cladding, contaminatedequipment, radioactive sludge andplutonium contaminated materialthat arises from both historic andcurrent operations. At Sellafield ILWis put into stainless steel drums,which are then filled with cementgrouting before being placed intoa special above-ground storagefacility on the site.Low level waste (LLW)Only slightly radioactive andincludes items such as protectiveclothing, laboratory equipment,paper towels and gloves which havebeen used in the controlled areasof a nuclear site, hospital or nuclearresearch centres. LLW is treatedat Sellafield’s Waste Monitoringand Compaction Plant – where it iscompacted, placed inside an ISOfreightcontainer and transportedfor disposal at the UK’s Low LevelWaste Repository.Exempt wasteExempt waste is deemed to becompactable bagged wasteclassified as exempt in accordancewith Radioactive Substances Act 93and is disposed of through an offsite landfill facility.Our purpose built facilitiesallow us to safely manageall types of nuclear waste.

We are committed to ensuringthat future waste generationis minimised and avoidedwherever possible.World class expertise in nuclear wastemanagement and minimisation.Capability and expertiseWaste management represents one of our mostsignificant activities and is a major area of expertise.The amount of waste generated at Sellafield isminute compared with the total industrial anddomestic waste produced each year in the UK.However, due to its radioactive content, we takegreat care to manage our waste using provenand effective methods of treatment and storageto ensure that the public and the environmentare protected. We do this by continually investingin significant resources and expertise to safelymanage all levels of radioactive waste.We are committed to theintelligent application ofthe Waste ManagementHierarchy in all aspectsof our waste activities.For the past 20 years we have been successfully treating andmanaging high level nuclear waste in our Vitrification Plant wherewe have the capability to convert high level waste into a solid,stable form suitable for permanent long term storage.Sellafield is the only nuclear site in the UK that provides an interimstorage facility for both high and intermediate level waste. It is alsothe only designated site in the UK that operates a purpose built lowlevel waste compaction facility.The Solvent Treatment Plant, which came into operation in 2000, isthe only facility in the UK which can process radioactive solvents toa safe end point compatible with a long term safe waste product.So far, 3,000m 3 of historic solvent stocks has now been processeddown to minimum inventory levels.Every aspect of our waste operations is conducted with due careand consideration for the environment.We are committed to ensuring that future waste generation isminimised and avoided wherever possible and are doing this bydeveloping our capability in waste sorting, segregation and sizereduction techniques. Likewise, ongoing studies into the options forminimising metal and demolition wastes through processes such asincineration will also help us ensure that maximum volume reductionis achieved.Sellafield is home to the UK’sonly high level waste treatmentand storage facilities.

ExpertsOn the Sellafield site we are dealingwith some of the most radioactivematerial known to man.

A number of projects and initiatives are under wayacross Sellafield Ltd to ensure that innovative solutionsare realised to enable the delivery of our integratedwaste management programme.Current waste projectsThe Integrated Waste Strategy is akey enabler in accelerated clean-upat the Sellafield site which will alsodeliver major benefits by reducingwaste volumes in the intermediateand low level waste categories.Laurence Cook, Head of WasteOur third Encapsulated Product Store (EPS3) isnearing completion and will provide additionalcapacity to support the two existing stores atSellafield which house intermediate level waste.EPS3 will take intermediate level waste arising from bothreprocessing operations and decommissioning work at Sellafield,providing interim storage for encapsulated waste on the site.Work to construct a sludge packaging plant (SPP1) at Sellafield isprogressing towards a completion date of 2014. The 1st buffer storagevessel has been assembled (33m long, 7m wide and 3.5m high) andtransferred into the building – representing the largest stainless steelfabrication on the site since the 1980s. A further two vessels are dueto be completed towards the end of 2012. Once completed, SPP1 willprovide the site with a designated facility for receiving and processinglegacy sludge retrieved from the first generation magnox storage pondprior to long term storage or disposal.Site preparation for the fourth Highly Active (HA) Liquid Evaporator(Evaporator D) began in 2008, with the first concrete pour of thebase slab in mid 2009. The site’s HA evaporators play a pivotal role inthe delivery of reprocessing, historic clean-up and hazard reductionmissions across the Sellafield site by concentrating the volume ofthe radioactive liquid waste through an evaporative heating process.AchievementsThe first ever high active wasteshipment from Sellafield to overseascustomers commenced in 2010 aspart of the Vitrified Residue ReturnsProgramme.With shipments undertaken from theUK to Japan and the Netherlands, thefirst two consignments were receivedsafely, securely and in full regulatorycompliance by June 2010.In 2011, our Miscellaneous Beta Gamma Waste(MBGWS) teams reached an impressive safetymilestone. Responsible for providing safe and securestorage for intermediate level waste, the team of30 worked 15 years without a lost time accident.15 yearswithout a lost timeaccident.

Evaporator D will provideSellafield will additionalevaporative capacity.The modules are beingdelivered to Sellafield bysea and installed using agantry on site.Evaporator D will provide additional evaporative capacity to supportthe site’s existing evaporators. Construction of the new facility willinvolve off-site fabrication of a series of large scale modules whichwill then be transported to the site by sea and installed into thebuilding’s concrete shell using a gantry system. This is the first timein the history of the Sellafield site that such large-scale modularconstruction will be used.A key milestone in reducing legacy wastes stored atSellafield will be reached with the return of vitrifiedresidue to overseas customers.In 2010 we started returning vitrified high level waste to overseascustomers in both Japan and Europe.The 10 year Vitrified Residue Returns programme, will seeapproximately 1,850 containers of vitrified (solid) waste returned tocustomers in fulfilment of contractual obligations.Delivery of this programme demonstrates the role that Sellafield Ltdis playing in substantially reducing the volume of solid highly activewaste temporarily stored at Sellafield.plant – the Residue Export Facility (REF) which will be used to loadvitrified (solid) highly active waste canisters into a flask for export toour customers in fulfilment of contractual obligations. In total, theUK will return approximately 1,850 containers of vitrified waste inaccordance with regulatory requirements.In addition to constructing and developing plants to deal withcurrent and future waste arisings, our Integrated Waste Strategyfor dealing specifically with low level waste is aimed at ensuringtechniques are implemented to minimise and where possible,avoid the generation of this category of waste.An average of 900 tonnes of metal a year is processed through ourWheelabrator facility which treats metal by mechanically removingthe outer surface. Once cleaned of contamination, the materialwhich includes redundant metal from decommissioning projects,skip handlers, ISO-freight containers and structural steel can berecycled back into the scrap metal market.One of the main benefits of our Integrated Waste Strategy is that ithas the potential to reduce the number of ISO-freights of low levelwaste disposed to the Low Level Waste Repository by more than30%, which is equivalent to 20,000 ISO-freight containers.In order to do this, we have commissioned a specially designedIn November 2010, our waste teamssafely processed almost the sameamount of plutonium contaminatedmaterial into a passive form over atwo year period compared to thatwhich had previously been processedin the previous 11 years.1,400 tonnesOur Metals Recycling Team processed over 1,400Tesof metal during 2011/2012 against a baseline target of950 tonnes and a stretch target of 1,350 tonnes. Thisincludes nearly 400Tes of metal shipped for off sitetreatment via the LLWR Segregated Services contractincluding 54-Multi element bottles. Over and abovethe 1,400Tes over 1,300Tes of clean metal has beendispatched off the site by the Metals Recycling Team.

Displaying uncompromising safety standards and arobust application of environmental management, ourvision going forward will be to continue supportingnuclear decommissioning and reprocessing programmesand in doing so, deliver value for money for our customer,the Nuclear Decommissioning Authority.Planning for futurewaste management.The futureWe have faced many technical and operationalchallenges in the field of waste management overthe past 50 years and have consistently deliveredworld class solutions and performance.In addition to supporting upstream plants including Magnox andThorp to ensure optimisation of the site reprocessing programmes,our key focus will remain on minimising the radioactive hazard ofmaterials held and produced at the Sellafield and Capenhurst sites.We will support the post operational clean out of nuclear waste inexisting facilities, as well as the clean-up of those buildings that arecurrently being decommissioned.Safely managing medium active wastes, continuing to safely exportvitrified high level waste and ensuring that we meet long termstorage requirements are among our key deliverables.Hazard reduction will be realised by using provenand effective methods as well as implementingnew waste treatment and disposal routes.Protecting the workforce, community and environmentin all our waste management operations.Reduction of highly active liquor stocks on the site will be achievedthrough safe and effective operation of the Waste VitrificationPlant which will enable us to meet regulatory requirements andprogramme end dates.Ongoing trials into the possible treatment of intermediate level wastefrom the Magnox Receipt and Storage Decanning Facility in theWaste Encapsulation Plant will continue.Following the successful completion of earlier trials involving thetransfer of sludge and solid waste to the Waste Encapsulation Plantfor encapsulation and safe storage, ongoing work will continue toenable the transfer of larger volumes of intermediate level wasteto the Waste Encapsulation Plant on a more continuous basis inthe future.Likewise, we will also maximise the use of existing liquid effluenttreatment and intermediate level solid waste plants for furtherdecommissioning solutions.We will continue to reduce the environmental impact of ouroperations in accordance with Best Practicable EnvironmentalOption principles. Continued application of our Integrated WasteStrategy will ensure that we minimise future low level wastearisings and where possible reduce the amount of low level wastesentenced to the Low Level Waste Repository as well as continuingto recycle waste where appropriate to do so.High level waste management.

ContinualimprovementThrough continual improvementand innovation we will confirmour position as world leadersin nuclear waste managementcapability and operations.Safety is Sellafield Ltd’s top priority

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