Presentations
Presented at the International Conference on Geologic Repositories, held 31 October - 3 November, 1999, in Denver, CO.
Transparencies from an invited presentation on
NON-PROLIFERATION ASPECTS
OF
GEOLOGIC REPOSITORIES
by JOHN P. HOLDREN
Director, Program on Science, Technology, & Public Policy John F. Kennedy School of Government
Professor of Environmental Science & Public PolicyDepartment of Earth and Planetary Sciences
HARVARD UNIVERSITY
Chair, Committee on International Security & Arms Control U.S. NATIONAL ACADEMY OF SCIENCES
International Conference on Geologic Repositories
DENVER, COLORADO
31 October - 3 November 1999
(presented 1 November, finalized for distribution 28 November)(views are the author's, not those of his institutions)
OUTLINE OF THE PRESENTATION
CONTEXT
Global quantities of civilian and military plutonium
Utility of civilian plutonium for nuclear weapons
COMPLEXITIES
Diverse threats, time scales, nuclear-energy & nuclear-weapon futures
Diverse waste-management options
Interactions of facts, perceptions, values
Interactions of the policies of diverse nations
CONTROVERSIES
How urgent is the need for geologic repositories?
What kind of spent-fuel storage in the meantime?
Must Pu be eliminated to control repository risks?
CONCLUSIONS
PREVIEW OF A PRINCIPAL CONCLUSION
The most important non-proliferation issue relating to geologic repositories is not the vulnerability or invulnerability of plutonium in the repository to theft or diversion in the short or long term.
The most crucial issue is, rather, the ways in which decisions about repositories --and, relatedly, about interim storage of spent fuel— may affect decisions about reprocessing and the inventories of separated military and civilian plutonium worldwide.
SOME RELEVANT QUANTITIES OF PLUTONIUM
(all numbers are metric tons, i.e., 1000s of kilograms)
WEAPON Pu IN WORLD STOCKPILES 250
OF WHICH OFFICIAL SURPLUS 100
TOTAL REACTOR Pu (as of end 1998) 1,120
OF WHICH
IRRADIATED (SPENT) FUEL 920
MOX FUEL 50
STORED OXIDE 150
ANNUAL PRODUCTION OF REACTOR Pu 65
ON THE UTILITY OF REACTOR-GRADE Pu FOR WEAPONS
Even if pre-initiation occurs at the worst possible moment (when the material first becomes compressed enough to sustain a chain reaction), the explosive yield of even a relatively simple device similar to the Nagasaki bomb would be of the order of one or a few kilotons. ... With a more sophisticated design, weapons could be built with reactor-grade plutonium that would be assured of having higher yields.
Committee on International Security & Arms Control, National Academy of Sciences, Management & Disposition of Excess Weapons Plutonium, Jan 1994
At the other end of the spectrum, advanced nuclear weapon states such as the United States and Russia, using modern designs, could produce weapons from reactor-grade plutonium having reliable explosive yields, weight, and other characteristics generally comparable to those of weapons made from weapons-grade plutonium.Final Nonproliferation and Arms Control Assessment of Weapons-Usable Fissile Material Storage and Excess Plutonium Disposition Alternatives, U.S. Department of Energy, Report No. DOE/NN-0007, January 1997
COMPLEXITIES: THREATS & TIME SCALES
THREATS
Diversion: covert or overt, large or small, from interim or final storage or from processing steps in between, by a host nation
Theft: covert or overt, large or small, from interim or final storage or processing steps in between, by another nation or subnational group
Loss of confidence in prevention of the above: leading to stopping or reversing progress in arms reductions, promotion of proliferation, weakening of institutions for safeguards & MPC&A
TIME SCALES Short term: next 10 years
Medium term: 10 - 25 years
Imaginable long term: 25 -100 years
Unimaginable long term: 100 - 100,000+ years
COMPLEXITIES: ALTERNATIVE NUCLEAR-ENERGY AND NUCLEAR-WEAPONS FUTURES
NUCLEAR ENERGY
Low-fission future: by around 2050, fission power has been or is being phased out every-where or nearly everywhere.
High-fission, low-recycle future: by 2050 or soon thereafter, fission power grows to $10 times its 1999 contribution (hence ~3300 GWe), using mainly once-through LEU (hence discharging ~70,000 MTHM/yr containing ~700,000 kgPu/yr).
High-fission, high-recycle future: same fission power as previous, based on ALMRs burning 20% Pu in MOX to 100,000 MWd/MTHM discharges ~30,000 MTHM/yr containing ~5,000,000 kgPu/yr, which is reprocessed & recycled.
NUCLEAR WEAPONS
Nuclear disarmament future: by around 2050, the world has achieved or moved decisively toward a global prohibition of nuclear weapons.
High proliferation future: by 2050 there are 15 or more nuclear-weapon states possessing 100s to 1000s of nuclear weapons each.
COMPLEXITIES: WASTE-MANAGEMENT OPTIONS
WASTE FORMS
Once-through spent fuel: LEU, WPu-MOX, RPu-MOX
Other immobilized forms: WPu, RPu in ceramics or glass, homogeneous or can-in-canister, with or without radiation barrier from mixed HLW or Cs-137
Reprocessed HLW and TRU wastes: various forms
INTERIM STORAGE FOR UNREPROCESSED FORMS
At the generating facility (reactors, immobilization sites): pools, dry storage in diverse configurations
Other: few/large/centralized or many/smaller/dispersed, co-located with envisioned geologic repository sites or not, national or international w resp to waste sources, ownership, MPC&A...
GEOLOGIC REPOSITORIES: One, or more, or fewer, per country; national or international w resp to waste sources, ownership, MPC&A; opened sooner or later; closed sooner or later
MORE EXOTIC OPTIONS: deep boreholes, seabed emplacement, space launch
CONCLUSIONS: ON THE RELATIVE PROLIFERATION VULNERABILITY OF ALTERNATIVE FORMS & OPTIONS
HUGE DIFFERENCE:
SEPARATED Pu vs. SPENT FUEL
BIG DIFFERENCE:
WELL PROTECTED vs. BADLY PROTECTED HEU & SEPARATED Pu
CLOSED REPOSITORY vs. INTERIM STORAGE
INTERNATIONAL vs. NATIONAL INTERIM STORAGE (in some cases)
SMALL-TO-MODERATE DIFFERENCE :
HOMOGENEOUS vs. C-IN-C IMMOBILIZATION
CENTRAL vs. AT-REACTOR INTERIM STORAGE IN A GIVEN COUNTRY
SMALL DIFFERENCES: REACTOR vs. WEAPON vs. "REPOSITORY" Pu
SPENT FUEL vs. HOMOGENEOUS IMMOBILIZATION
LEU SPENT FUEL vs. MOX SPENT FUEL
CONCLUSIONS: NEAR-TERM THREATS & PRIORITIES
The greatest proliferation dangers in the decades immediately ahead will be associated not with spent fuel and immobilized Pu forms meeting the Spent Fuel Standard, but with separated military and civilian Pu, with HEU in the military and civilian sectors, and with the operations that continue to produce and handle these directly weapons-usable materials.
Minimizing the inventories and flows of these materials and maximizing the protection afforded to them are therefore of paramount importance, including, in the last connection, accelerating efforts to improve MPC&A for the large inventories of HEU & separated plutonium in the FSU.
From the nonproliferation standpoint, the most important aspect of decisions made in the decades immediately ahead about interim storage and geologic repositories for spent fuel and immobilized waste forms will be the effects of these decisions on
(a) incentives to refrain from reprocessing, and to reduce existing inventories of separated Pu by once-through irradiation in MOX and by immobilization with wastes; (b) confidence in the institutions for, commitment to, and continuity of progress in moving weapons-usable nuclear materials into proliferation-resistant forms in difficult-to-access locations.
A timely and orderly progression toward emplacement in geologic repositories - with centralized interim storage along the way if repositories can't be available in a timely way - is important in both respects (as well as for the public's perception that the radioactive-waste problem is under control).
For at least the next two decades, the United States and Russia - and probably the other nuclear-weapon states - will retain substantial reserves of HEU and separated military plutonium. If such states choose to build up their arsenals, they will use these materials first, and Pu and HEU from manipulating the output of existing fuel-cycle facilities second.
In this same time frame, most non-nuclear weapon states & subnational groups seeking to acquire weapons will find it easier to divert or steal the needed materials from military & civilian stocks of HEU and separated Pu - or (in the case of states with sizable nuclear-energy programs) to manipulate the output of existing fuel-cycle facilities - than to steal & reprocess spent fuel or Pu immobilized with HLW.
There are circumstances, however, in which certain potential proliferant states might find the reprocessing of spent-fuel in their possession to be an attractive route to nuclear weapons. Regional, internationalized interim-storage facilities or geologic repositories would provide useful protection against this danger.
CONCLUSIONS: LONGER-TERM THREATS
In the medium term and the imaginable long term (out to 100 years hence), large uncertainties attend both the role of nuclear energy and the status of nuclear arsenals worldwide. The combinations of circumstances under which closed geologic repositories might be attractive sources of plutonium for theft or diversion in this time frame constitute only a narrow subset of the possible circumstances.
These potential long-term proliferation risks from geologic repositories are sufficient to justify planning for international safeguards for closed (as well as open!) geologic repositories, and to justify building into repository design some practicable barriers against clandestine re-excavation after repository closure.
It would be wildly premature, however, to conclude that residual proliferation risks from closed spent-fuel repositories, in the narrow range of circumstances in which such risks could be significant at all, would be greater than the proliferation risks of reprocessing-recycle-transmutation programs aimed at minimizing the amounts of plutonium sent to repositories.
Continuing research both on reducing the proliferation vulnerability of spent-fuel repositories and on proliferation-resistant approaches to reprocessing-recycle-transmutation is desirable, but there is no need and no basis for an early decision to deploy the latter.
The argument that we should reprocess & recycle now, using existing technology, in order to limit the accumulation of plutonium in spent fuel, is particularly misguided.
To do this would make worse a large proliferation vulnerability that is here now - associated with large stocks and flows of directly weapon-usable material in civilian nuclear energy systems - in order to try to make smaller a longer-term, lower-order, vastly more uncertain risk associated with spent fuel in repositories.
Not only would this constitute the classic blunder of making a big problem bigger in the course of trying to make a small one smaller; it would also incur additional penalties insofar as reprocessing/recycle with existing technologies is -- economically costlier than the once-through fuel cycle
-- more accident-prone than once-through
-- a bigger routine emitter of radionuclides than once-through
As for the very long term ($100 years hence), because we cannot even imagine either its technical or its political characteristics, we should not take any action today based on conceptions about it except research to understand the possibilities and develop options.
CONCLUSIONS: ABOUT THE CONTROVERSIES
How urgent is the need for geologic repositories?
From a nonproliferation standpoint, moving in an orderly and timely way toward certifying, opening, filling, and closing geologic repositories brings important benefits, related largely to incentives for shrinking the inventories of directly weapon-usable materials and to confidence in the intended irreversibility of these reductions, but also related ultimately to the additional physical barriers that closed repositories provide. This is an "all deliberate speed" issue, not a "complete it immediately" issue. We should not be in such a hurry that we make mistakes in repository selection and design. What kind of spent-fuel storage in the meantime?
The case for moving rapidly from at-reactor storage to centralized interim storage facilities is not generally compelling on nonproliferation grounds except where public opposition to providing adequate at-reactor storage is generating incentives to reprocess or where unusual national circumstances make stored spent fuel a potentially attractive source of weapons material for the state that generated the fuel. When and where centralized interim storage is pursued, it should be done in ways that do not imperil a timely transition to geologic repositories.
The third question, "Must Pu be eliminated to control repository risks?", was answered in my ruminations about the long-term a moment ago: "Certainly not now!"
A RECOMMENDATION ON INTERNATIONAL COOPERATION
A recent panel I chaired for the White House on international cooperation on energy-technology innovation concluded that increased cooperation was warranted in the study of both geologic-repository issues and international interim-storage facilities. Here is the relevant passage from that report:
[The United States should] expand and strengthen international cooperative efforts in studies and information exchange on geologic disposal of spent fuel and high-level wastes, to include expanded participation, studies of international interim-storage facilities, and development of a consistent and rigorous international regulatory framework for both interim storage and geologic disposal of these materials.
President's Committee of Advisors on Science and Technology, Powerful Partnerships, Report of the Panel on International Cooperation on Energy Technology Innovation, Executive Office of the President of the United States, June 1999
[at www.whitehouse.gov/WH/EOP/OSTP/PCAST]
SELECTED REFERENCES (chronological)
John P. Holdren, "Radioactive Waste Management in the United States: Evolving Policy Prospects and Dilemmas", Annual Review of Energy and The Environment 17: 235-259, 1992.
Committee on International Security and Arms Control, National Academy of Sciences, Management and Disposition of Excess Weapons Plutonium, Vol. 1 (January 1994), Vol. 2 ("Reactor-Related Options", July 1995), National Academy Press.
US Department of Energy, Final Proceedings: Plutonium Stabilization and Immobilization Workshop, 12-14 December 1995, Conf-951259.
Per F. Peterson, "Long-Term Safeguards for Plutonium in Geologic Repositories", Science and Global Security 6: 1-29 (1996)
David Albright, Frans Berkhout, and William Walker, Plutonium and Highly Enriched Uranium 1996, Oxford University Press, 1997.
National Research Council, Committee on Separations Technology and Transmutation Systems, Nuclear Wastes: Technologies for Separation and Transmutation, National Academy Press, 1997.
Matthew Bunn and John P. Holdren, "Managing Military Uranium and Plutonium in the United States and the Former Soviet Union", Annual Review of Energy And The Environment, 22, 1997.
Edwin S. Lyman and Harold A. Feiveson, "The Proliferation Risks of Plutonium Mines", Science & Global Security 7:119-128 (1998)
Luther J. Carter and Thomas H. Pigford, "The World's Growing Inventory of Spent Fuel", Arms Control Today, January/February 1999, pp 8-14.
David Albright and Lauren Barbour, "Separated Inventories of Civil Plutonium Continue to Grow", ISIS Plutonium Watch, May 1999, http://www.isis-online.org/publications/ puwatch/putext.html
Matthew Bunn, "Enabling a Significant Future for Nuclear Power: Avoiding Catastrophes, Developing New Technologies, Democratizing Decisions -- and Staying Away from Separated Plutonium", in Proceedings of Global 99: Nuclear Technology -- Bridging the Millennia, Jackson Hole 30 August - 2 September 1999, American Nuclear Society, 1999.
Allison Macfarlane, "Standoff at Yucca Mountain: High-Level Nuclear Waste in the U.S.A.", in Geology's Gaze: Looking Toward a Livable Future, Jill Schneiderman, ed., W. H. Freeman, 1999 (forthcoming).