Selected chapters from:

Fissile Materials in a Glass, Darkly:

Summary and Recommendations

• Return to Beginning
• Chapter 1: Plutonium and Highly Enriched Uranium as Liabilities
• Chapter 2: Criteria for Plutonium Disposition
• Chapter 8: Policy Issues
• Table of Contents to the Full Report
• Ordering Information

Summary and Recommendations

Despite the progress that has occurred between the United States and Russia on many nuclear-weapons-related issues, neither country has a coherent policy for disposition of nuclear materials. Russia is unlikely to act without U.S. leadership and reciprocity, especially given the rising nationalist sentiment that has accompanied economic decline in Russia in the last two to three years. There are already signs that such sentiment may take the form of Russian government policies favoring of preserving large stores of weapon-usable fissile materials and nuclear weapons, rather than reducing them. (1) Thus, the U.S. must develop its disposition policy with an eye to its effects in Russia. Given the danger that a global black market in weapons-usable fissile materials originating in Russia may develop, it is imperative that the United States choose a disposition policy and persuade Russia to do the same.

Weapons-usable plutonium also arises from the reprocessing of civilian spent fuel and this must be included in overall disposition policy. The governments of five key countries -- Russia, France, Japan, Britain, and India -- regard plutonium as a valuable long-term energy resource. They continue to operate reprocessing plants to separate plutonium from civilian spent fuel, but their capacity to use plutonium has lagged far behind the rate of its production. As a result, surpluses of civilian plutonium continue to mount, including in Russia. The United States is the only leading country that has wisely rejected the use of civilian plutonium because of its proliferation dangers and its high costs. It is therefore the only country that is in a position to exercise the leadership to persuade other countries to forgo civilian plutonium production at least for the time being, and to put all separate plutonium into non-weapons-usable forms.

Low uranium prices and an abundant resource base mean that plutonium will not be an economically viable nuclear fuel for many decades (if ever) even for those who regard it as a valuable resource for the long-term. This could provide a basis for attempting to achieve an interim, but universal, halt to civilian and military reprocessing. U.S. disposition policy must be compatible with exercising the leadership to get to this goal. An interim halt to reprocessing would allow time for the energy and security issues associated with plutonium to be negotiated without continuing to separate plutonium in the meantime.

Most studies have advocated that the United States consider the option of turning plutonium into highly radioactive spent fuel by "burning" some of it nuclear reactors as plutonium-uranium mixed oxide (MOX) fuel. Despite some advantages of this approach, it would create an infrastructure for long-term use of plutonium as a fuel in civilian power plants. This is highly undesirable from a non-proliferation standpoint, and has no economic advantages whatsoever.

Appropriate institutional arrangements for managing nuclear-weapons-usable materials for the long-term are needed. The DOE has made great progress on openness at the national level; it created a new office for disposition of nuclear materials in January 1994. It has also boldly taken the lead in rejecting the Advanced Liquid Metal Reactor, which would legitimize plutonium-based fuels, for plutonium disposition, despite pork-barrel pressures to continue funding it. Yet, nuclear weapons spending continues to be very high. This is evidence that the hold of the nuclear weapons makers, which produced conflicts on interest regarding health and environmental issues in the past, continues to be strong, despite the end of the Cold War. It remains to be seen whether the gains of the past few years, and notably of the last two on openness at the national level can be generalized throughout the weapons complex and sustained. Accomplishing that consolidation is essential to successful implementation of disposition policy.

Our principal recommendations for plutonium disposition are as follows:

• The United States should formally declare excess plutonium a security, economic, and environmental liability, and forswear its re-use in weapons.

• The U.S. should adopt vitrification of plutonium as the strategy for putting plutonium into a non-weapons-usable form. It should forgo all options that involve the use of any reprocessing or reactor technologies for plutonium disposition, in order to help promote the objective of an interim, global halt to reprocessing and to discourage the use of plutonium as a fuel in other countries.

• In the next two years, the U.S. should build three or four pilot plants for the vitrification of plutonium so that any technological problems can be cleared up prior to large-scale implementation, and so that the choice of the best vitrification technology can be made on the basis of a technically sound Environmental Impact Statement on vitrification under the National Environmental Protection Act.

• The U.S. should take the initiative in the creation of an international financial guarantee for the re-extraction of plutonium from glass, should it become an economical fuel in the future. It should link this guarantee to achieving an interim, global halt to reprocessing and vitrifying all civilian and all excess military plutonium globally. Appropriate restraints, including public hearings, must be built into this guarantee, so that plutonium is not re-extracted without a clear and unequivocal economic justification. On no account should plutonium be re-extracted for use in weapons.

• A reserve of low-enriched uranium (LEU) reactor fuel, created by blending down HEU into LEU, should be created so that an alternative to plutonium will be available for decades.

It does not appear at this stage that there are any serious technical hurdles to the implementation of this policy, which is based on combining already commercial technologies. If this policy is carried out from the beginning with due attention to environmental, health, and safety concerns of workers and the communities near proposed facilities, it should be possible to put all separated civilian and all excess military plutonium into non-weapons usable form in a decade or less once the political decision is made to do so.

Other Findings and Recommendations - Plutonium

• There is no satisfactory solution for plutonium disposition that addressees all important security and environmental concerns for all time frames. We must choose from a menu of options that are all partly unsatisfactory in some respects.

• The U.S. should evaluate three options for plutonium vitrification:
  1. Vitrification of plutonium mixed with gamma-emitting fission products so that the resulting glass logs meet the spent fuel standard;
  2. Vitrification of plutonium mixed with depleted uranium, or some other similar alpha-emitting element;
  3. Vitrification of plutonium with a non-radioactive element, such as europium, that would render the extracted mixture unusable for weapons without expensive and difficult processing.

• Vitrification of plutonium alone could also be considered, but it does not appear to present a sufficient barrier to re-extraction by sub-national groups, and therefore is probably unacceptable from a non-proliferation standpoint.

• The "spent fuel standard" for military plutonium disposition -- that is, making plutonium as difficult to re-extract as it is from civilian power plant spent fuel -- would be the most appropriate one for the short and medium-term if the only concerns were technical ones of re-extraction difficulty and protection against diversion. Such a standard for disposition using vitrification is currently unacceptable to countries that are reprocessing civilian spent fuel because of the very high cost of re-extraction and because vitrification does not extract any energy from plutonium. The security criteria for evaluation of the choice of a disposition policy should include the potential of the policy to contribute to the goal of an interim, global halt to reprocessing and the speed at which all civilian plutonium and excess military plutonium can be put into non-weapons-usable forms.

• An option with lower re-extraction costs compared to the spent fuel standard but still high enough to pose great challenges to sub-national groups should be explored. Such an option may help to further the goal of achieving a universal, interim halt to reprocessing. If there were financial guarantees for plutonium re-extraction, should it become economical for civilian power production in countries that are now reprocessing civilian spent fuel, these countries may agree to vitrify their plutonium. Vitrification of plutonium with alpha-emitting heavy metals, such as depleted uranium (or other elements with low gamma-emitting properties belonging to a class of elements called actinides), or with certain non-radioactive elements, such as europium or gadolinium, are options that could meet this criterion if there are appropriately high levels of plutonium dilution. The glass so produced should be safeguarded at the same level as plutonium pits or nuclear warheads. (Pits are the metal spheres that form the nuclear triggers of warheads.) This option by itself will not meet the spent fuel standard, especially so far as resistance to diversion is concerned.

• One way of achieving the spent fuel standard and still having a disposition policy that is compatible with policies needed for an interim halt to reprocessing would be to vitrify plutonium with rare earths or actinides first and add a gamma-emitting fission product, such as cesium-137, to the canister (instead of adding fission products to the glass). This would provide the same high resistance to theft as spent fuel and also greatly reduce the amount of fission products for achieving it compared to the option of mixing the fission products in the glass itself. As a result worker exposures and other health and environmental risks may be lower compared to other spent fuel standard options. A feasibility study and laboratory experiments should be initiated to examine this option. This option appears to be the most promising of all the options that we have examined for achieving the principal disposition goals to the maximum feasible extent.

• The U.S. should address disposition of plutonium scrap and residues as part of its overall plutonium disposition plan. Because of proliferation concerns, it should rule out all options for processing of residues that, in practice, promote development of reprocessing technologies, such as pyroprocessing. The inclusion of residues in disposition policy will also be very important for non-proliferation and materials accounting in Russia. The U.S. should stop funding the development of pyroprocessing even as a plutonium disposition option. One pilot plant for plutonium vitrification should be devoted to the problem of processing of scrap residues. According to our preliminary evaluation the use of a new technology for direct vitrification of residues, developed by Oak Ridge National Laboratory, appears to be a promising choice for this plant.

• The use of the existing vitrification plants at Savannah River Site, South Carolina and West Valley, New York, presents severe practical difficulties. A feasibility study to examine the use of the plant at Savannah River Site for plutonium vitrification at the time when the melter is scheduled to be replaced should be initiated. The start-up of these two plants for high-level waste vitrification should not be delayed because of their potential use for plutonium vitrification.

• The security problems arising from plutonium cannot be fully resolved even in theory until there is a halt to nuclear power, since nuclear power plants generate plutonium. The U.S. Department of Energy should initiate a fresh evaluation, with full public participation, of the long-term security issues arising from the use and spread of nuclear power plants in light of the severe practical difficulties that have arisen in considering disposition of excess military plutonium.

Other Findings and Recommendations - HEU

• Unlike plutonium, HEU could, in principle, be blended down to provide an economical nuclear power reactor fuel substitute for uranium from mines, so long as there is a market for such fuel.

• The use of LEU made by blending down HEU as a substitute for mined uranium has a number of environmental advantages, such as preventing the accumulation of new radioactive mill tailings and saving energy used in uranium enrichment. These advantages can be realized only if blending down is done in strict conformity with U.S. health and environmental laws. It should be noted that this conclusion assumes that a substantial fraction of existing nuclear power plants will continue to operate for at least the next decade-and-a-half or so. It does not address any environmental or economic issues associated with continuing to run particular nuclear power plants relative to implementing efficiency measures and/or building other types of power plants to replace nuclear capacity.

• The potential re-enrichment of LEU, especially using gas centrifuge technology, will continue to pose proliferation risks even after HEU is blended down.

• The potential advantages of using LEU derived from HEU are partly offset by the realities that U.S. blending down capacity is at present small and verification provisions in Russia to ensure that HEU is actually being blended down are not in place. As a result, storage of HEU in the United States and Russia will continue for a considerable time unless the pace of implementation is increased. Long storage periods increase security risks from potential black-market sales, notably of Russian HEU. Greater capacity for blending down HEU is needed in the near-term, if the blending down option is pursued.

• The U.S. should adopt a policy of reciprocity vis-(-vis Russia as regards HEU disposition policy. This will lead to a more equitable and secure reduction of a larger portion of global HEU stocks than planned under the current U.S.-Russian agreement.

• Vitrification of HEU as an interim measure may reduce security risks arising from the potential for black market sales. However, it may also make the use of future use of LEU derived from vitrified HEU uneconomical relative to LEU from mined uranium. Prior to choosing an option, the DOE should include in its Programmatic Environmental Impact Statement on disposition of fissile materials a careful evaluation, with full public participation, of the security and environmental concerns of extended HEU storage compared to conversion of larger amounts of HEU to LEU and vitrification of much or most HEU.

• Return to Beginning
• Chapter 1: Plutonium and Highly Enriched Uranium as Liabilities
• Chapter 2: Criteria for Plutonium Disposition
• Chapter 8: Policy Issues
• Table of Contents to the Full Report
• Ordering Information

Institute for Energy and Environmental Research

Comments to Outreach Coordinator: ieer@ieer.org
Takoma Park, Maryland, USA

Last Updated April 17, 1996