June 20, 2011 - IMM@BUCT

clear fuel will have decayed to the point thatit will no longer be greatly more dangerousthan pure uranium in transient equilibriumwith 4 billion years of decay products.While it is a fact that present fuel reprocessingplants are expensive and tendto pollute their surroundings with leakedfission products, it is also a fact that onlyabout 3% of the potentially available fissionenergy in that fuel has been extracted. Tryingto dispose of that fuel such that it willbe hidden from humanity for thousands ofyears is not likely to be successful, since ina few hundred years our descendants willbe looking for it as a source of energy—andthey will have much greater technical capabilitiesfor processing it than we have. Itmight be best to put it in steel and concretecanisters, such as those now used at nuclearpower plants to store aged dischargedfuel, and simply park it out in the Nevadadesert to keep company with the debrisfrom several hundred past weapons tests.The heart of your editorial was that fissionenergy sources aren’t going to go away,and that should be abundantly obvious toyour readership. The potential energy densityof uranium and thorium is hundreds ofmillions of times that of fossil fuels, whereassolar, wind, and agricultural energysources are diffuse and inadequate to ourneeds by orders of magnitude. The 22ndcentury is much more likely to see thoriumcycle power plants than fusion plants inwidespread use, and it would be hystericalnot to expect such a development.Jacques ReadOcean City, Md.I READ WITH unusual interest the lettersin the May 9 issue. The problem of disposalof the waste nuclear products from reprocessingspent fuel rods is a major concern.BiomassPlasticExtrusionPetrochemicalsOil Recovery SupportPump withConfidenceReactant Feed+LJK3UHFLVLRQ+LJK3UHVVXUH6\ULQJH3XPSV 8VHRXUSXPSVIRUDSSOLFDWLRQVVXFKDVELRIXHOVUHDFWDQWIHHGFRUHÁRRGLQJDQGSODVWLFIRDPLQJ 3XPSDOPRVWDQ\WKLQJLQFOXGLQJKLJKO\YLVFRXVÁXLGVVXFKDVKHDY\RLOVSRO\PHUVVOXUULHVDQGSDVWHV 6WDQGDUGSXPSVGHOLYHUVXEPLFUROLWHUWRPOPLQZLWKRUEHWWHUDFFXUDF\HOW TO REACH USCHEMICAL & ENGINEERING NEWSLETTERS TO THE EDITOR■ Our e-mail address is edit.cen@acs.org.■ Our fax number is (202) 872-8727.■ Or you can send your letter to:C&EN Editor-in-Chief1155—16th St., N.W.Washington, DC 20036■ Letters should generally be 400 words orfewer and should include the writer’s full name,address, and home telephone; letters maybe edited for purposes of clarity and space.Because of the heavy volume of mail receivedat C&EN, writers are limited to one letter in asix-month period.Core FloodingView our technical library atwww.isco.com/spappnotes&DOOXVWRVHOHFWRUFXVWRPL]HDSXPSWRPHHW\RXUVSHFLÀFQHHGVLVFRLQIR#WHOHG\QHFRPWWW.CEN-ONLINE.ORG 7 JUNE 20, 2011