Efforts to Manage and Irreversibly Reduce Existing Stocks of Fissile Material

in the Nuclear Weapon States

by Kevin O'Neill

Deputy Director, Institute for Science and International Security (ISIS)

Paper presented to the "Fissile Material Information Workshop"

sponsored by ISIS and the Canadian Mission to the Conference on Disarmament

Geneva, Switzerland

January 25 - 26, 1999

(as delivered)


The United States and Russia have proposed and in some cases initiated a number of measures to provide each other with information about their nuclear weapons and fissile material stocks and to ensure each other and the international community that their arms reductions will not be reversed. The consideration of such measures results from decisions made after the end of the Cold War to scale back nuclear weapons production capabilities and to end the nuclear arms race between the United States and Russia. As such, these measures broaden the traditional nuclear arms control agenda. They include providing more information about military stocks and production capabilities, declaring portions of these stocks to be excess, verifying that excess materials are not returned to weapons, and disposing of these materials in ways to make future weapons-use very difficult or impossible.

Making information about fissile material stockpiles and production activities more open to scrutiny by other governments and international agencies is already an accepted condition in most countries. Making civil nuclear programs open to such scrutiny has long been a central goal of International Atomic Energy Agency (IAEA) full-scope safeguards where, for example, governments allow international inspectors to verify that stocks of nuclear material are not diverted to purposes proscribed by the NPT. The decision last year by key states with large civil plutonium stocks--including both weapon states and non-weapon states--to make public the size of these stocks also contributes to the openness of civil nuclear programs.

In contrast to civil programs, military programs are characterized by secrecy and not openness. The notion that making military nuclear programs more accountable actually contributes to and does not detract from national security has not been universally accepted. Only the United States and Britain have taken steps to make their military stocks of fissile material more open.

In cases where nuclear weapons exist, achieving disarmament through a step-wise process (as the United States and Russia prefer) requires more than information about stockpiles and production histories. Measures also are required to assure that reductions are undertaken in a permanent manner. There is no analogy for these steps in the non-weapon states, since they presumably lack unsafguarded fissile material or nuclear weapons.

To be sure, many of the proposals and initiatives undertaken to reduce the size of military fissile material stocks are proceeding slowly. The "newness" of these concepts and ideas in the weapon states partially accounts for this slow progress. Other reasons include the residual legacy of secrecy about nuclear weapons, technical difficulties, and financial considerations. So far, these steps have largely been confined to unilateral initiatives and bilateral proposals and initiatives between the United States and Russia. Britain has also provided more information about its military stocks. Nevertheless, a process of providing information about and reducing military fissile material stocks has begun.

Providing Information about Military Fissile Material Stocks and Production

To date, some of the weapon states have found it acceptable to declare unilaterally some information about their military fissile material stocks. The United States and Russia have also pledged to exchange, on a bilateral basis, information and data about fissile materials and nuclear weapons.

Unilateral Transparency Measures. The United States and the United Kingdom have unilaterally declared information about their military fissile material stocks. In February 1996, the United States released a report detailing information about U.S. plutonium stocks, and their production, acquisition and use. In addition to declaring the U.S. plutonium inventory, the report provides detailed information about historical plutonium acquisitions from military production reactors, other government reactors, civilian industry and from foreign countries. On the other side of the balance, the report describes quantities of plutonium consumed in nuclear tests, losses to waste and through decay, fission and transmutation and through transfers abroad. In most cases, data are presented in annual increments. A special effort is also made to describe so-called inventory differences between amounts of plutonium accounted for in the books and in the actual physical inventory.

The United States is also compiling a report on HEU. Like the plutonium report, the HEU report is expected to include detailed information about how much HEU is currently in the inventory, how and when it was acquired, and how much has been lost through tests, fission or transmutation and through waste, and other categories. Although the data has been collected for this report, its release awaits declassification approval from elements of the Department of Defense--a process that has taken much more time than originally expected.

In 1998 Britain released aggregate totals of its fissile material stocks as part of its Strategic Defense Review. Britain also pledged to compile reports on the historical production, acquisition and use of fissile materials that are to be similar to the U.S. reports.

The undertaking that these reports represent should not be underestimated. In the case of the U.S. HEU report, it was necessary to review literally millions of transactions. From the early years of the program through the late 1960s, many of these records were kept on hand-written ledger sheets or other perishable forms, and in some cases the original methodology used to keep track of production was difficult to understand. Definitions and methodologies used to compile operating records and transactions were not always uniform or consistent from site-to-site or year-to-year. The process of records collection and analysis was further complicated by the closure of facilities and the retirement or death of those involved in the earliest years of the program.

Bilateral Initiatives. In addition to these unilateral measures, several proposals have been offered for the sharing of information about nuclear weapons and fissile material inventories on a bilateral, U.S.-Russian basis. However, little has been done to fulfill these pledges.

In March 1994, the U.S. and Russian nuclear energy establishments agreed to establish a mutual reciprocal inspection regime to confirm inventories of plutonium and HEU removed from dismantled nuclear weapons. Subsequently, at their September 1994 summit, presidents Clinton and Yeltsin broadened the transparency agenda to include the exchange of "detailed information" on "aggregate stockpiles of nuclear warheads [and] on stocks of fissile materials." In May 1995, Clinton and Yeltsin called for an additional agreement on "other cooperative measures, as necessary to enhance confidence in the reciprocal declarations on fissile material stockpiles."

None of these agreements have been carried out. While there were some initial reciprocal visits between the two countries, mutual reciprocal inspections were never implemented because of a lack of an agreement between the United States and Russia to exchange classified information. The proposed data exchanges were never carried out for the same reason, and negotiations on an agreement to exchange classified information have not occurred since late 1995. The two sides also failed to reach an agreement on other cooperative measures, as called for in the May 1995 summit, after Russian negotiators balked at a U.S. proposal to open all fissile material sites, except for sites containing intact nuclear weapons and naval fuel, to reciprocal visits. A U.S. government official who was involved in creating the U.S. proposal later said that the proposal was too sweeping for the Russians to accept.

Bilateral transparency was revived in March 1997 at the Helsinki summit between Clinton and Yeltsin. As part of a joint statement on the parameters of the START III talks, Clinton and Yeltsin agreed that the treaty would include "measures relating to the transparency of strategic nuclear warhead inventories and the destruction of strategic warheads."The two presidents also "agreed that the two sides will consider the issues related to [the] transparency in nuclear materials" during the negotiations. The United States introduced this proposal and linked it to arms reductions in part to satisfy Russian concerns about the ability of the United States to quickly rearm its multiple warhead missiles under START II. However, the Russian Duma has still not ratified START II, and enthusiasm for transparency, stockpile information exchanges and warhead dismantlement may be fading away.

Reducing Military Stocks of Fissile Materials

In parallel to initiatives to provide more information about military fissile material stockpiles, some of the nuclear weapon states have also begun the process of reducing their fissile material stocks. This process involves declaring portions of their military stocks to be excess, placing these stocks under a form of verified or monitored storage to ensure that they are not returned to weapons use, and disposing of these stocks in a manner that makes it difficult to reuse these materials in weapons.

At present, the United States, Russia and Britain have declared portions of their military stocks to be excess to military needs. Some of these stocks have been placed under voluntary IAEA safeguards or, in the case of Britain, under Euratom safeguards. For the remainder of these materials, special procedures are being negotiated with the IAEA to ensure that excess materials are used only for non-explosive purposes.

Declaring and Verifying Excess Materials. The United States has declared roughly 226 tonnes of fissile material, including 174 tonnes of HEU of various enrichments and 52 tonnes of plutonium to be excess. These materials are in a variety of forms and are spread across many U.S. nuclear weapons production complex sites. A substantial portion of the excess plutonium is in the form of weapons or weapons components, but the vast majority of the U.S. excess material is composed of impure plutonium and HEU byproducts of the nuclear weapons production process.

Russia has declared, at least in theory, a much larger quantity of fissile material to be excess. In September 1997, at the IAEA General Conference, Russia announced "the decision to remove gradually from military programs up to 500 tonnes of HEU and 50 tonnes of plutonium which has become available through the nuclear disarmament process." The Russian announcement followed a previous decision to blend down and sell 500 tonnes of excess HEU to the United States over a 20-year period.

The United Kingdom is the latest nuclear weapon state to declare a portion of its stocks to be excess. As part of its 1998 Strategic Defense Review, Britain announced that 4.4 tonnes of plutonium, including 300 kilograms of weapon-grade plutonium, are excess to military needs. However, Britain failed to declare any of its HEU to be excess, reserving its materials for nuclear propulsion purposes.

Verifying the excess stocks in the United States, Russia and the United Kingdom has slowly followed their declarations. Of the U.S. excess, 10 tonnes of HEU and 2 tonnes of plutonium have been placed under voluntary IAEA safeguards. In addition, the IAEA verified that 3.5 tonnes of HEU, out of a total of 13 tonnes, was blended down to LEU in 1997 - 1998. Additional amounts of fissile material--including 15 tonnes of plutonium and 50 tonnes of HEU-- have been offered for safeguards or other forms of verification, which would begin at unspecified dates.

The United Kingdom's excess plutonium, nearly all of which is not weapon-grade, is to be placed under Euratom safeguards. All but a very small fraction of this material has already been placed under Euratom safeguards.

Unlike the United States and Britain, Russia has not placed any of its excess materials under international safeguards at this time. However, technical measures have been used by the United States and Russia to confirm the blending of the excess Russian HEU to LEU. In addition, the United States has agreed to accept measures to verify that the resulting LEU is not re-enriched for weapons purposes once it reaches the United States.

Under current plans, Russia's excess plutonium stock is to be placed in a new storage facility that is now under construction with U.S. assistance. Under U.S. Congressional direction, continued U.S. support for the construction of this facility has been linked to the successful negotiation of procedures that would allow U.S. inspectors to verify that the materials placed in this facility originated from weapons. So far, U.S. and Russian negotiators have failed to reach this verification agreement.

The Trilateral Initiative.
One reason for the slow pace of placing excess materials under international controls is the need to protect sensitive information about nuclear weapons. To address this concern, the United States, Russia and the IAEA are parties to the Trilateral Initiative, where they are negotiating formal procedures to provide for the verification of fissile materials that contain sensitive information about the design, manufacture or performance of nuclear weapons. Under this effort, the three parties are seeking to "define the verification measures that could be applied at Russia's Mayak storage facility ... and at one or more U.S. facilities" that store excess fissile materials. The trilateral initiative is also exploring the legal and financial aspects of internationally verifying excess fissile material stocks.

The main issue of the Trilateral Initiative is to devise appropriate techniques and procedures for the long-term, verified storage of classified forms of plutonium, which could include weapon components. To shield inspectors from classified information, it is expected that the United States and Russia would verify bilaterally that the materials originated from weapons, while the IAEA would be left to draw "independent and meaningful conclusions" that the bilateral verification is correct. While many questions remain unresolved, the testing of prototype equipment and the development of specific verification approaches at different facilities are now under way.

The parties to the Trilateral Initiative are also seeking to develop a model verification agreement, which would form the basis for future bilateral agreements between the IAEA and each weapon state to verify weapon-origin fissile materials. The proposed model agreement is to be more restrictive than current voluntary offer agreements; once materials are submitted, they would remain under IAEA verification until they are determined to be unusable for the manufacture of nuclear weapons. Draft agreements are now being considered by the U.S. and Russian governments.

The Trilateral Initiative has also begun to consider options for financing. In September 1998, the IAEA Director General suggested the creation of an IAEA Nuclear Arms Control Verification Fund as a possible way to provide necessary financial support. However, other options are likely to be considered, as well.

Disposition of Excess HEU and Plutonium

The final issue is the disposition of excess fissile materials. The national security objective of disposition is to render excess military fissile material stocks unusable or unattractive for use in nuclear weapons. Efforts to arrive at acceptable disposition arrangements are progressing slowly. The main obstacles are related to finances and domestic political controversies, rather than government secrecy or international politics. Russia and the United States have found that it difficult and expensive to eliminate their excess fissile material stocks.

HEU Disposition. HEU disposition has already begun. In 1993, the United States and Russia agreed to a complicated arrangement that would blend down 500 tonnes of excess, Russian-origin weapon-grade uranium to low enriched uranium that is suitable for fuel for light water reactors. Such uranium could not be used for nuclear explosive purposes unless it were to be re-enriched.

Through the end of 1998, approximately 50 tonnes of HEU had been blended down to LEU, resulting in nearly 1,500 tonnes of low-enriched fuel. As previously mentioned, verification arrangements in Russia have been put into place to ensure that the Russian HEU is, in fact, weapon-grade. In the United States, arrangements have also been made to ensure that the transferred LEU is not re-enriched to weapon-usable levels.

The technological process of blending HEU to LEU is relatively straightforward. But fluctuations in the commercial uranium market have plagued the HEU Purchase Agreement from the beginning. In November 1996, the U.S. and Russia agreed to a five-year price and quantity schedule to provide some predictability in the agreement. In addition, the agreement increased the amount of HEU to be blended down through 2001 to 150 tonnes, or about 50 percent more than the original schedule.

Last August, problems in the HEU agreement were amplified following the privatization of USEC, the U.S. executive agent of the agreement, and the decision by USEC to sell more than 70 million pounds of uranium on the open market over the next several years. Predictably, this lowered uranium prices, making it difficult for Russia to recoup much of the revenue they expected to generate. U.S. and Russian negotiators are now trying to resolve this crisis, and public statements by U.S. government officials indicate that they may be close to a solution.

The United States also is blending down excess HEU. By the end of 1998, about 13 tonnes of HEU has been blended down. Between 1999 and 2005, an additional 50 tonnes of excess U.S. HEU is to be blended down. The remaining materials are to be blended down or disposed of as waste through 2015 under current schedules.

Plutonium Disposition. Plutonium disposition in the United States and Russia has proven more difficult to start. Last September, after several years of technical discussions between the U.S. and Russian governments, Presidents Clinton and Yeltsin pledged: (1) to convert approximately 50 tonnes each of excess military plutonium to forms that are unusable for nuclear weapons; (2) to cooperate in this goal through burning this excess plutonium in reactors or immobilizing it in high-level waste; (3) to encourage the participation of other governments and private industry in this effort; (4) to develop and operate an initial set of industrial scale facilities to convert military plutonium to forms usable in nuclear reactors; (5) to seek to develop international verification measures to be applied to the disposition programs; and (6) to seek appropriate financial arrangements. Shortly thereafter, the U.S. Congress appropriated $200 million to support cooperative plutonium disposition efforts. Negotiations on an agreement to fulfill the Clinton-Yeltsin pledge are now underway.

The joint statement by Clinton and Yeltsin follows several years' worth of discussion and analysis in both Russia and the United States about how to best dispose of its excess plutonium. In essence, the statement summarizes the conclusions of this discussion at the present time. The objective of the plutonium disposition effort in both countries is to reach the "spent fuel standard"--that is, to make excess military plutonium as attractive for use in nuclear weapons as commercial spent fuel. However, many factors may yet complicate the implementation of plutonium disposition in either country.

For Russia, the question of plutonium disposition is relatively straightforward. Russia has proposed to burn as much of this plutonium as possible as mixed oxide ("MOX") fuel in nuclear reactors. It has suggested that several existing light water reactors and one breeder reactor may be used for the mission. Additional reactors would be built, if necessary. However, Russia lacks the infrastructure to convert its weapons plutonium to oxide and to fabricate MOX fuel for these reactors. Notwithstanding the on-going discussions and negotiations with western countries, including the United States, France and Germany, to provide the necessary facilities, whether or not there will be the financing needed to support the Russian plutonium disposition program remains to be seen.

In the United States, the plutonium disposition program is the subject of intense domestic political controversy. The United States has officially adopted a dual-track strategy for plutonium disposition, which would burn much of the excess plutonium in reactors as MOX fuel and immobilize the rest. However, the United States officially halted its civil plutonium recycle program in the late 1970s, and strong opposition remains in some quarters to using military plutonium to fuel civilian reactors. The U.S. also lacks the facilities needed to convert plutonium to oxide and to fabricate MOX fuel. At the same time, proponents of the so-called "MOX track" argue that the United States must pursue the reactor option to maintain a credible dispostion program in the eyes of Russia and others in the international community.

Conclusion and Observations

To conclude, several observations about efforts to reduce stocks of military fissile materials are offered:

1) Among the efforts undertaken to date, the easiest steps have had the most success. HEU dispostion, which is technically straightforward and carries relatively little political controversy, has made the most progress among the tasks discussed here. On the other end of the spectrum, providing information about military stocks and production capabilities, and the declaration that portions of these stocks are now excess to military requirements, remain highly controversial and have not been universally accepted by the weapon states. However, taking the easy steps paves the way for the more difficult ones that await attention.

2) The steps that need to be taken to reduce military fissile material stocks are expensive. It will cost billions of dollars to safeguard existing facilities; construct new facilities to store and convert excess materials; and to convert weapons materials to forms for civil use. The issue of cost should not be surprising, given the trillions of dollars that were spent during the Cold War to develop and maintain nuclear arsenals. In this regard, the participation of the international community to help fund the costs to reduce military fissile material stocks is essential.

3) Time is also a factor. The development and construction of new facilities can not be accomplished over night. It will also take time to overcome bureaucratic inertia and the Cold War legacy of secrecy that continues to define nuclear weapons and the management of military fissile material stocks. Meanwhile, steps need to be taken to ensure that whatever gains are made towards reducing fissile material stocks are not lost through inattention.

4) Reducing military fissile material stocks is not a linear process. For every two steps forward, there is often one step back. Obstacles include not only those directly related to the process of disarmament, but also to the broader domestic political and national security environments of the countries involved.

Nevertheless, a process of verifiably reducing military fissile material stocks has begun. To be sure, many steps are only in their infancy and in some cases are awaiting to be born. But the progress that has been made so far paves the way for additional steps that would significantly reduce the threat posed by military fissile material stocks. Each of these initiatives need time, resources and attention to grow.