by Arjun Makhijani and Michele Boyd
Institute for Energy and Environmental Research
Paper presented at the Krasnoyarsk conference on plutonium disposition on June 5, 2000

The end of the Cold War has seen many positive developments as well as some negative ones. One of the more positive developments has been that both Russia and the United States have declared 50 metric tons each of military plutonium surplus to their military requirements. Governments and NGOs alike share the goal of safely and securely storing this plutonium in a form in which it cannot be used to make nuclear weapons. There are two basic ways to do this: immobilization, which would put plutonium into a ceramic matrix and then a glass waste form so that it cannot be used in weapons or mixed oxide (MOX) fuel for nuclear reactors, mostly light water reactors. In our view, the approach of converting this plutonium into a reactor fuel is not a sound one for a number of reasons.

According to the agreement arrived at by Presidents Clinton and Putin on June 4, 200, each side will disposition 34 metric tons of plutonium at a rate of at least 2 metric tons per year. The United States will used immobilization for 8.5 metric tons and MOX fuel for 25.5 metric tons. Russia will convert all 34 metric tons into MOX fuel at a plant to be built in Russia with western money. The United States and Russia will bring this up at the G-8 meeting in Okinawa in July. The United States and Russia have also agreed that future surplus plutonium will be dealt with in a similar way.

The United States and Russia lack only a MOX fuel fabrication plant and some related processing facilities to complete the infrastructure for MOX fuel production. Once that is done, there will be an incentive to continue plutonium separation, which would entrench plutonium use. And indeed, the US-Russian agreement would allow Russia to reprocess MOX spent fuel after the 34 metric tons of plutonium are used as MOX fuel. The MOX spent fuel can be expected to contain a large amount of residual plutonium, since only a fraction of the plutonium will be used as fuel. At the same time new plutonium will be made from the depleted uranium that is part of MOX fuel and also from the uranium fuel that will be used in part of the reactor core.

The MOX program will increase proliferation and safety concerns, while also increasing the cost for disposition and the waste generated in the process. Immobilization will cost less, be completed faster, and produce less waste that even one-time use of MOX. The US-Russian plutonium agreement is unsound and should be rejected by their people. It is even worse than we had anticipated because all of the discussions leading up to the summit led us to believe that Russia would immobilize at least some plutonium, so that some of the money would have been used to create an immobilization infrastructure in Russia. Under the present agreement, there is no provision for such an infrastructure in Russia, though one would be built in the United States.

First, I will discuss some of the problems with the MOX program in more detail. Then, I will discuss an alternative plan based on immobilization that has been supported by more than 150 groups from several countries, including the United States, Russia, Britain, Japan, and so on. A letter describing this plan was sent to Presidents Clinton and Putin on June 1.


A MOX fuel program would create the infrastructure of facilities and financial interests for continuing “commercial” plutonium use. Once begun for weapons plutonium, the MOX plant is likely to be used for plutonium separated from commercial spent fuel. This intent is explicit in Russia, and currently denied in the United States. But once the plant is there, it will be politically difficult to shut it. As evidence, we point to the fact that two military reprocessing plants are still operating at Savannah River Site in South Carolina, supposedly for reasons of “environmental management.” In the same way, Russia is also operating two military reprocessing plants, one at Tomsk-7 and the other at Krasnoyarsk-26, as a way of managing its spent fuel. So what was once a plutonium separation technology for military and commercial purposes has become a waste management tool!

Like weapons-grade plutonium, commercial plutonium can also be used to make nuclear weapons. A MOX program would put these materials on the roads and in commercial nuclear power plants. At every step of the MOX process until it is loaded into a reactor and its irradiation has begun, the plutonium would need to be safeguarded with a military level of security. This is because plutonium can be separated from the uranium in MOX fuel by relatively simple steps and facilities compared to reprocessing spent fuel. The MOX production facilities, transport to power plants, and its storage at power plants would all be points of potential theft. Unless steps are taken to militarize security at these facilities, there will be a risk of diversion of weapons-usable, including weapons-grade, plutonium.

Proponents of the current US-Russian MOX plans argue that a moratorium on reprocessing of MOX spent fuel during the disposition program would be a sufficient safeguard against proliferation. But it is irrelevant whether MOX spent fuel is reprocessed now or in a few decades. There is plenty of other spent fuel to reprocess now, without this MOX spent fuel. There is already about 30 metric tons of separated commercial plutonium at Chelyabinsk-65 that is not addressed under the disposition plan. This can keep reprocessing plants going until the moratorium on MOX spent fuel reprocessing expires. So the net result will be that first military plutonium will be used in the MOX plant, while commercial spent fuel is reprocessed to build up the commercial plutonium stock. Then the MOX spent fuel can be reprocessed while the already separated commercial plutonium is fabricated into MOX fuel. This seems to be the plan the Minatom is banking on.


The vast majority of light water reactors were not designed to use plutonium as a fuel. Several specific differences between MOX fuel and low-enriched uranium fuel affect safety:

  • The rate of fission of plutonium tends to increase with temperature. This is called a positive temperature coefficient of reactivity and can adversely affect reactor control.
  • Reactor control depends on the small fraction of neutrons emitted in the seconds to minutes following fission of uranium or plutonium. These neutrons are called delayed neutrons. On average, plutonium yields about three times less delayed neutrons per fission than uranium. This means that provisions must be made for increased reactor control if MOX is used. Otherwise, the reactor would become more unsafe. How many more control elements are needed, where they must be placed and whether any particular reactor can be modified to accommodate MOX fuel, are questions that must be examined with very specific light water reactor design. For instance, only one of the three designs of pressurized water reactors that are being used in France for power production can be modified to accept MOX fuel.
  • MOX fuel also causes more irradiation damage to the reactors than traditional fuel, because the neutrons resulting from MOX fuel use in light water reactors have a greater average energy than those resulting from uranium fuel. This is due to differences in the fission cross sections between plutonium and uranium in various parts of the thermal neutron spectrum.
  • Irradiated MOX fuel is thermally hotter than uranium fuel because of the larger quantities of transuranic elements produced during reactor operation with MOX fuel, which complicates repository disposal of MOX spent fuel.

The larger amount of transuranic elements, like americium, present in irradiated MOX fuel makes it far more dangerous in the case of an accident. According to a report by Dr. Edwin Lyman from the Nuclear Control Institute in Washington, DC, the public health consequences of severe accidents involving light water reactors with MOX cores are likely to be considerably greater then those involving low-enriched uranium (LEU) cores. This is because the higher proportion of plutonium in the fuel would increase the release of plutonium and other transuranic elements to the environment in case of a severe accident. Proposed funding by the United States for safety upgrades of Russian VVER-1000 light water reactors will only cover modifications to bring the reactors up to Russian safety standards.

I understand that, historically, VVER-1000 reactors have experienced significant problems in the past, just using the uranium fuel for which they were designed. Vladimir Kuznetsov, a reactor expert, who worked for Gosatmonadzor for many years, Russia’s nuclear regulatory agency, has expressed seroius concerns about VVER-1000 reactor safety and published a book on the subject. Use of MOX fuel in VVER-1000 reactors would greatly complicate the issues associated with the operation of these reactors. It would become more complex to assess the conditions of their safe operation, for example.

We urge our Russian colleagues to undertake and evaluation of whether these safety standards would be comparable to those in the United States. Not to say that we are happy with the safety standards there. Many of us believe that regulation is too lax in the United States. In my opinion, the US Nuclear Regulatory Commission has not exercised adequate oversight in the process of selection of which reactors might be suitable or not for MOX fuel use. In fact, it has allowed commercial interests to dominate the process by allowing any reactor owners to bid for MOX fuel contracts. A prudent process would Have ruled out some reactors on the basis of design or other safety considerations.

One specific problem in Russia is that Gosatmonadzor appears to have far less authority over actual decision-making in regard to licensing and operation of facilities compared to the Nuclear Regulatory Commission in the United States. And while the US NRC might seem a good model to you from afar, many of us are dissatisfied with the degree of oversight that it exercises over nuclear power plants. Moreover, Gosatomnadzor will likely depend on US money for regulating MOX fuel use. This is a serous vulnerability and shows the relatively weak position of this agency in the Russian nuclear establishment.

Another safety issue specific to weapons grade plutonium is that it has never been used as a commercial fuel. Reactor-grade plutonium has different isotopic characteristics than weapons-grade plutonium. Reactor grade plutonium from light water reactors has roughly 60 percent plutonium-239. Weapons-grade plutonium has about 94 percent plutonium-239. The US Department of Energy is proposing 40 percent MOX fuel in the reactor core, compared to 30 percent which is normal in the reactors which use MOX fuel in France. This means that in US reactors fueled with MOX, there will be about 38 percent plutonium-239 as fuel, compared to about 24 percent for commercial reactors, an increase of more than 50 percent. Despite this crucial difference, the US Department of Energy intends to use the computer codes from French reactors using commercial MOX fuel to analyze weapons plutonium MOX performance in reactors. We believe that such large extrapolations from commercial experience would create significant uncertainties about safety.

In Russia, the pressure to increase the MOX fuel loading of the core will be even greater. Achieving the 2 metric tons per year rate disposition rate in Russia has been a concern, because the number of Russian light water reactors is limited. Moreover, all of the existing reactors that are under consideration for MOX will reach the end of their 30-year lifetimes within the next 25 years and many of them much earlier. The pressure to extend the lifetimes of the reactors will be very great. Other possible measures include using 100% MOX cores in the BN-600 reactor, using reactors in Ukraine, or using CANDU reactors in Canada. All of these approaches pose additional safety risks that that have not been adequately addressed.


In order to satisfy US demands, Minatom has agreed to use MOX in light water reactors, rather than breeder reactors as they would prefer. So far as we understand, Minatom had never seriously considered the use of MOX fuel in its light water reactors, until the United States brought the idea to the table as part of the military plutonium disposition plan. This raises some liability questions, such as who will pay for the costs, if an accident should occur in a light water reactor using MOX fuel.

According to Laura Holgate, head of the Office of Fissile Materials Disposition in the US Department of Energy, the liability issue has been a major outstanding issue to be resolved in the US-Russian agreement. However, it is naïve to think that, even if an agreement on liability is reached, it will prevent problems if an accident occurs. It is possible that an accident in an LWR using MOX fuel could cause a serious political crisis over liability between the two countries, because the MOX program in light water reactors is a US government program, especially if the Russian government agrees to assume the liability for the program. In the United States, the Price-Anderson Act provides free insurance to nuclear power plant owners in case of an accident up to a limit of $10 billion dollars. The plant owners themselves have very little liability. Beyond this limit, the public would have to bear the costs, unless special legislation is passed to compensate them. Although $10 billion is highly inadequate for addressing a large nuclear accident, such a level of financial compensation would be unlikely in Russia. Moreover, any liability agreement between the US and Russia will not cover damage to third countries. As we know from the experience of the Chernobyl accident, such damage can be substantial.

In case the US government agrees to assume a portion of the liability, it is far from certain that the US Congress would actually provide the money, should it be needed. This could create its own set of political difficulties. In sum, the liability for use of MOX fuel in Russian light water reactors presents a very difficult problem, even if the US and Russia can arrive at a paper agreement on how to address it.


The current estimate is that the Russian MOX program will cost $1.7 billion and the US program will cost about $4 billion. According to the US Department of Energy, this cost estimate does not include many items such as the cost of insurance or the costs of electricity while the reactors are shut down for modifications. These costs could be significant, and it is likely that the Russian people would have to pay them. Even though plutonium will be used to generate electricity, the use of MOX fuel will involve net costs. This because it is more expensive to fabricate MOX fuel even when the plutonium is free Than it is to purchase low-enriched uranium fuel. In addition, the extra security, which will add to the cost of the whole process, has not been adequately considered in the evaluation of the MOX program.

The total amount of the net cost of the MOX plan is a matter of some debate. It will depend on the actual costs of processing weapons grade plutonium into MOX fuel and the costs of reactor modifications, as well as the time it will take to make reactor modifications and to certify the reactors as safe, and so on.

A considerable amount of discussion has revolved around the financing of the Russian portion of the plutonium disposition plan. In order for the MOX plan to be implemented, the G-8 meeting in July must decide on a financing approach. Then the Parliaments of the countries that agree to contribute must agree to this plan and provide the money.

It is also possible that private financing might be developed. One financing plan has been put forward by a US corporation known as the Non-Proliferation Trust, Inc. This would involve importation of up to 10,000 metric tons of foreign spent nuclear power reactor fuel for storage in Russia, a complete halt to commercial reprocessing, and a payment to Russia for building storage facilities, a nuclear waste repository and other purposes. Such a plan is currently illegal under Russian law and hence attempts are being made to amend the law. However, the Russian people are overwhelmingly opposed to such a plan, as demonstrated by polling and by the firm opposition of environmental NGOs in Russia. Many US NGOs and those in other countries also oppose this plan.

The commercial plutonium industry is dying in Europe. A US-Russian MOX program would help resuscitate it and renew hopes for a plutonium economy in the nuclear establishments of the two countries. Some of the beneficiaries of such a change would be European companies, whose contracts are drying up at home because of increasing skepticism about the worth of plutonium as an energy source. British Nuclear Fuel, Ltd. (BNFL) has lost contracts to make MOX fuel from commercial plutonium for Japan, Germany, Sweden, and Switzerland due to scandals over the company’s environmental and safety records. The French reprocessing company, COGEMA, faces an uncertain future with its main customer, Electricite de France, because of the higher costs of MOX fuel relative to uranium fuel. Cogema is now part of the consortium to fabricate MOX fuel from weapons-grade plutonium at Savannah River Site (SRS) in the United States.

In our view, it would be far better to spend money developing wind energy resources, since wind power is already more economical that MOX fuel use in reactors. IEER has published a report on this subject and a summary has been published in our newsletter.

Alternative Plan

Simply opposing the MOX program is unlikely to be enough to stop it. It is necessary for the international NGO community to support an alternative plan for plutonium disposition. This is because the underlying goal of putting plutonium into non-weapons usable form is a sound one that is shared across the political spectrum and across the world. At IEER, we have worked with our colleagues in the United States, Russia, France, and Germany to develop an alternative plan based on immobilization. We have sent this proposal to Presidents Putin and Clinton as a sign-on letter, which included more than 150 groups from the US, Russia, France, Germany, England, Canada, and Australia. Many of the people and groups at this conference are signatories to this letter.

According to this plan, the immobilization of plutonium, which Russia and the US have adopted for only a small proportion of the plutonium, should be extended to cover the full amount for both surplus weapons and all separated commercial plutonium in both countries. This is a safer, faster, and more economically efficient option. It involves putting plutonium into a non-weapons usable form by mixing it with other materials and making the resultant waste form proliferation resistant. The MOX option should be discarded.

The plan also requires a halt to commercial reprocessing. The immobilized plutonium in each country would be stored in that country under International Atomic Energy Agency (IAEA) safeguards. Furthermore, Russian plutonium is to be leased or purchased by the West. The price would be the value of the fuel normally used in light water reactors low enriched uranium equivalent of the MOX that could be make out of the plutonium, not including the fuel fabrication costs of MOX. The West would also pay for the immobilization of plutonium in Russia.

There are numerous potential funding mechanisms for this program.

  • G-7 countries could contribute to the cost.
  • The European Union could create a Russian plutonium fund.
  • A small tax could be imposed in the European Union on natural gas imported from Russia to fund the program.
  • The United States could supply part of the funds.
  • NATO could contribute to the plan, as it will enhance security for all of its members.

These funding mechanisms are not mutually exclusive.

The next step in promoting an alternative proposal to MOX is for the international NGO community to pressure their governments to financially support this plan. We are planning a fax campaign for NGOs and individuals to show their support for this plan from now until the G-8 meeting at the beginning of July. We hope that the G-8 will seriously consider our alternative plan at that time. We believe that our alternative plan is a far better approach to plutonium disposition. It will provide the Russian people with financial benefits, and at the same time be better overall for the environment, for safety, and for non-proliferation.

The debate should be shifted back to the real central issues: the need to reduce the weapons-useable stocks of plutonium in both the US and Russian and to provide safe, theft proof storage. Immobilization followed by secure storage would be a safer, faster, and more economical way to address these goals.