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Options and Choices in the Disposition of Excess Weapon Plutonium

Published online by Cambridge University Press:  15 February 2011

R. L. Garwin
R. L. Garwin*
Affiliation:
IBM Fellow Emeritus, IBM, T.J. Watson Research Center, P.O. Box 218, Yorktown Heights, NY 10598, RLG2, at, watson.ibm.com, and Member of the National Academy of Sciences study on disposition of excess weapon plutonium
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Abstract

More than 50 tons of weapon-related plutonium (WPu) is expected to become excess andavailable for disposition by the year 2003 in Russia and a similar amount in the United States.Per two reports from the Committee on International Security and Arms Control of the NationalAcademy of Sciences (1994 1 and 1995 2), the hazard of theft and incorporation into nuclearweapons impels us to guard this Pu carefully and as soon as possible to transform it into a formless accessible for use in nuclear weapons. To this end, CISAC adopted the “Spent FuelStandard” for the disposed WPu, which, if met, renders the WPu no greater hazard per kg thanthe much larger amount of reactor Pu in the form of spent fuel, since CISAC finds that separatedRPu can be used for nuclear weapons with little additional difficulty beyond that posed byseparated WPu. Many disposition routes can be eliminated on the basis of cost or other metric.The two principal survivors (of about equal cost and difficulty for the United States) are thepartial burning of WPu as MOX and the direct vitrification of WPu (as oxide) with high-level‘defense wastes’. Both these approaches should be pursued urgently, with experiments toqualify the processes, until one is selected on the basis of hard evidence. Either approach wouldcost about $1 B, within a factor two, to dispose of 50 tons of excess WPu. The CISAC analysiswill be presented, with comments on utility of RPu in weapons, on the DOE PlutoniumDisposition Study, and on ‘explosive criticality’ in the repository.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 412: Symposium V – Scientific Basis for Nuclear Waste Management XIX , 1995 , 3
Copyright
Copyright © Materials Research Society 1996

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References

1. Panofsky, W.K.H. (Study Chair), Management and Disposition of Excess Weapons Plutonium, Report of the National Academy of Sciences, Committee on International Security and Arms Control, (National Academy Press, Washington, D.C. 1994).Google Scholar
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3. Not just plutonium removed from excess weapons, but also weapon-grade Pu that has never been in weapons, is in the form of scrap or dust, etc.Google Scholar
4. But according to the U.S. 1994 Nuclear Posture Review, it is planned to retain “reserve” warheads so that the total U.S. stock in the year 2003 would be about 8000. Personally, it seems to me that the benefit to U.S. security of limiting the total number of Russian nuclear warheads to 3500 (including any reserves), needs to be weighed against the value of U.S. reserve weapons.Google Scholar
5. One gram of high-explosive yields about 4.2 kJ, so one ton is 4.2 GJ, and one KT is 4.2 TJ. The nuclear weapons used against Hiroshima and Nagasaki were on the order of 20 KT, so almost 100 TJ.Google Scholar
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11. Why should it have been? After forming Pu239 from neutron capture on U238, continued operation of a reactor then burns up that Pu239 by fission and by capture of additional neutrons to form Pu240. Furthermore, WPu provides a lesser radiation dose to the nuclear weapon workers and the military in handling and storage than does RPu.Google Scholar
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