FACILITATING NUCLEAR DISARMAMENT: Verified Declarations of Fissile Material Stocks and Production

Abstract

Unprecedented interest in seeking progress toward nuclear disarmament exists today; even some nuclear weapon states are looking for new ways to strengthen this process. National declarations of fissile material holdings—highly enriched uranium and plutonium—could play an important role in supporting this effort, facilitating not only transparency but also the irreversibility of the process. This article discusses what kind of content such declarations could have in order to be meaningful and effective, the sequence of data on fissile material holdings that states might release, and some of the challenges to be expected in reconstructing historic fissile material production; it also summarizes current attitudes of weapon states toward making such declarations. Initial declarations can be valuable as confidence-building measures, but better and more background data are necessary if declarations are to serve as the groundwork for deeper cuts in the nuclear arsenals. A robust verification approach would ultimately require inspectors to have access to fissile material production and storage sites. The methods and tools of nuclear forensic analysis—in this context also dubbed nuclear archaeology—would be a key element of this process. This article discusses the capabilities and limitations of potential approaches to verifying declarations of historic production of plutonium and highly enriched uranium; it also identifies and discusses opportunities for further research and development.

Keywords:

• Disarmament
• nuclear weapons
• fissile material
• highly enriched uranium
• plutonium
• verification

Notes

1. This article is based in part on Chapters 3 and 4 of International Panel on Fissile Materials (IPFM), “Global Fissile Material Report 2009: A Path to Nuclear Disarmament,” October 2009, <www.ipfmlibrary.org/gfmr09.pdf>. The author was the lead writer for those chapters.

2. “Final Document, 2010 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons,” vol. 1, pt. I, Actions 19–22, Section F: “Other Measures in Support of Nuclear Disarmament,” NPT/CONF.2010/50, New York, 2010.

3. In July 2009, the US government declared that, “as of May 2009, the United States had cut its number of operationally deployed strategic nuclear warheads to 2,126, which meets the limits set by the [2002 Moscow] Treaty for 2012.” See “The Legacy of START and Related U.S. Policies,” State Department, fact sheet, July 16, 2009. Similarly, in May 2010 the US government announced that, as of September 2009, its “stockpile of nuclear weapons consisted of 5,113 warheads.” See “Increasing Transparency in the U.S. Nuclear Weapons Stockpile,” Department of Defense, fact sheet, May 3, 2010. As part of the implementation of New START, the United States recently revealed very detailed quantitative information about its strategic forces. See Hans M. Kristensen, “US Releases Full New START Data,” FAS Strategic Security Blog, December 12, 2011, <www.fas.org/blog/ssp/2011/12/newstartnumbers.php>; and “New START Treaty Aggregate Numbers of Strategic Offensive Arms,” compiled by Hans M. Kristensen, Federation of American Scientists, December 7, 2011, <www.fas.org/programs/ssp/nukes/armscontrol/NewSTART-USnumbers090111.pdf>.

4. See Chapter 1 in IPFM, “Global Fissile Material Report 2010: Balancing the Books,” December 2010, <www.ipfmlibrary.org/gfmr10.pdf>.

5. IPFM, “Global Fissile Material Report 2009,” p. 32.

6. “Nuclear Posture Review Report,” Department of Defense, April 2010, <www.defense.gov/npr/docs/2010%20nuclear%20posture%20review%20report.pdf>.

7. As the United States pointed out in 1993, disclosing the amount of HEU it had produced “could have valuable nonproliferation benefits by making potential International Atomic Energy Agency safeguards arrangements easier to implement.” Echoes of this sentiment could be seen in a 2006 statement accompanying the UK release of fissile material data: “the U.K. believes that transparency about fissile material acquisition for defence purposes will be necessary if nuclear disarmament is to be achieved; since achieving that goal will depend on building confidence that any figures declared for defence stockpiles of fissile material are consistent with past acquisition and use.” For the US statement, see “Declassification of Today's Highly Enriched Uranium Inventories at Department of Energy Laboratories,” US Department of Energy, June 27, 1994, <www.ipfmlibrary.org/doe06a.pdf>; and for the UK statement, see “Historical Accounting for UK Defence Highly Enriched Uranium,” UK Ministry of Defence, March 2006, <www.ipfmlibrary.org/mod06.pdf>.

8. For more on this, see IPFM, “Global Fissile Material Report 2009,” pp. 33–34.

9. Good discussions can be found in Nicholas Zarimpas, ed., Transparency in Nuclear Warheads and Materials: The Political and Technical Dimensions (Oxford: SIPRI, Oxford University Press, 2003); and in IPFM, “Banning the Production of Fissile Materials for Nuclear Weapons: Country Perspectives on the Challenges to a Fissile Material (Cutoff) Treaty,” September 2008, <www.ipfmlibrary.org/gfmr08cv.pdf>.

10. “Presentation of Le Terrible in Cherbourg,” speech by President Nicolas Sarkozy, March 21, 2008, <www.ipfmlibrary.org/sar08.pdf>.

11. For a recent independent fissile material inventory estimate and a discussion of France's production history, see Alexander Glaser, “Military Fissile Material Production and Stocks in France,” 52nd Annual Institute of Nuclear Materials Management Conference, July 17–21 2011, Palm Desert, California.

12. France's production facilities are concentrated at two sites: Marcoule (plutonium production) and Pierrelatte (uranium enrichment), both in the south of France, and dismantlement activities are under way at both sites. France could offer these sites as test-beds and partner with one or more countries in a verification exercise to demonstrate new approaches for historic fissile material production. See Glaser, “Military Fissile Material Production and Stocks in France.”

13. Even though there have not been any recent official steps toward more openness in Russia, it is worth noting that more information is gradually becoming available through memoirs and historical documents that have been published over the past few years. See, for example, Chapters 3 and 4 in IPFM, “Global Fissile Material Report 2010: Balancing the Books: Production and Stocks.”

14. At the time, Russia considered sharing information on the quantities and storage locations of fissile materials recovered from dismantled nuclear weapons and also offering the materials for IAEA safeguards. Anatoli Diakov, “Russia,” in IPFM, “Banning the Production of Fissile Materials for Nuclear Weapons,” pp. 42–44. These offers were put forward in a statement by Ambassador Grigori Berdennikov, “Setting the Context for the Cut-Off Treaty,” Workshop on Fissile Materials, Toronto, Canada, January 17, 1995.

15. Hans M. Kristensen and Robert S. Norris, “Chinese Nuclear Forces, 2011,” Bulletin of the Atomic Scientists 67 (November/December 2011), pp. 81–87.

16. Ministry of Foreign Affairs of the People's Republic of China, “Fact Sheet: China: Nuclear Disarmament and Reduction of [sic],” April 27, 2004, <www.ipfmlibrary.org/prc04.pdf>.

17. Li Bin, “China,” in IPFM, “Banning the Production of Fissile Materials for Nuclear Weapons,” pp. 7–13.

18. This assumes that China would not restart fissile material production for weapons, which might be impossible anyway without refurbishing or rebuilding shutdown production facilities. It is also worth mentioning some transparency measures that China has taken recently; for example, it has opened up for visitors a previously unknown underground production complex that was never finished (“816 Underground Nuclear Project”), see Chapter 7 in IPFM, “Banning the Production of Fissile Materials for Nuclear Weapons.”

19. See IPFM, “Banning the Production of Fissile Materials for Nuclear Weapons,” for estimates. Pakistan has several new plutonium production reactors under construction, while India has kept outside of safeguards large quantities of weapon-grade plutonium that it could turn into weapon-grade plutonium using its breeder program.

20. Zia Mian and A.H. Nayyar, “Playing the Nuclear Game: Pakistan and the Fissile Material Cutoff Treaty,” Arms Control Today, April 2010, <www.armscontrol.org/act/2010_04/Mian>.

21. Harald Müller, “The Nuclear Weapons Register: A Good Idea Whose Time Has Come,” PRIF Report No. 51, Peace Research Institute Frankfurt, June 1998.

22. IPFM, “Global Fissile Material Report 2009,” Appendix 3A.

23. The sentence read: “Our current defence stocks are 7.6 tonnes of plutonium, 21.9 tonnes of highly enriched uranium and 15,000 tonnes of other forms of uranium.” “Strategic Defence Review: Modern Forces for the Modern World,” Ministry of Defence, July 1998, Section 72, <www.ipfmlibrary.org/mod98.pdf>. The United Kingdom released more detailed declarations on historical plutonium and HEU accounting in 2000 and 2006, respectively. See “Historical Accounting for UK Defence Highly Enriched Uranium.”

24. “Plutonium: The First 50 Years: United States Plutonium Production, Acquisition and Utilization from 1944 through 1994,” Department of Energy, DOE/DP-0137, 1996, <www.ipfmlibrary.org/doe96.pdf>; see also “Highly Enriched Uranium: Striking a Balance. A Historical Report on the United States Highly Enriched Uranium Production, Acquisition, and Utilization Activities from 1945 through September 30, 1996,” Draft, Rev. 1., Department of Energy, January 2001 (publicly released in 2006), <www.ipfmlibrary.org/doe01.pdf>.

25. In fact, even the initial declarations of the non-nuclear weapon states made upon joining the NPT were never explicitly verified for completeness. As part of the IAEA's INFCIRC/153 negotiations, “the [International Atomic Energy] Agency shall be provided with an initial report on all nuclear material which is to be subject to safeguards thereunder.” See IAEA, “The Structure and Content of Agreements Between the Agency and States Required in Connection with the Treaty on the Non-Proliferation of Nuclear Weapons,” INFCIRC 153 (corrected), Section §62, June 1972, <www.nti.org/db/nisprofs/fulltext/treaties/inf153.html>.

26. One example, of course, is North Korea. Western estimates are as high as 60 kilograms, but North Korea in 2008 reportedly declared a total production of only 37 kilograms. It is quite possible that low capacity factors, fuel failures, and losses to waste can explain this difference. Nuclear archaeology would provide the methods and tools to resolve this discrepancy. Similar situations could possibly apply to all nuclear weapon states.

27. When irradiated spent fuel is dissolved in acid to recover plutonium, gaseous fission products are released. Radioactive isotopes of the noble gases are emitted to the atmosphere because they pose little risk to the environment. Among these, krypton-85 is a particularly useful indicator for reprocessing because its concentration in the irradiated fuel scales directly with the amount of fission in the fuel. Also, due to its half-life of 10.8 years, krypton-85 gradually accumulates in the atmosphere.

28. Frank von Hippel, David H. Albright, and Barbara G. Levi, “Stopping the Production of Fissile Materials for Weapons,” Scientific American 253 (September 1985), pp. 40–47.

29. C.J. Gesh, “Graphite Isotope Ratio Method Primer—A Method for Estimating Plutonium Production in Graphite Moderated Reactors,” Pacific Northwest National Laboratory, PNNL-14568, February 2004, <www.pnl.gov/main/publications/external/technical_reports/PNNL-14568.pdf>.

30. For an excellent discussion and a review of several case studies, see: Thomas W. Wood, Bruce D. Reid, John L. Smoot, and James L. Fuller, “Establishing Confident Accounting for Russian Weapons Plutonium,” Nonproliferation Review 9 (Summer 2002), pp. 126–37.

31. Alex Gasner and Alexander Glaser, “Nuclear Archaeology for Heavy-Water-Moderated Plutonium Production Reactors,” Science & Global Security 19 (2011), pp. 223–33.

32. M. Sharp, “Applications and Limitations of Nuclear Archaeology,” unpublished draft, as quoted in IPFM, “Global Fissile Material Report 2010: Balancing the Books.”

33. Russia has been particularly secretive about the isotopics of its weapons plutonium and HEU. In contrast, the Unites States has revealed data on both.

34. IPFM, “Global Fissile Material Report 2009: A Path to Nuclear Disarmament,” p. 57.