A great deal has been written about surplus military plutonium, including a considerable amount of literature produced by IEER, the US National Academy of Sciences, and others. In January 2001, IEER released a report on management of commercial plutonium, and how its disposition could and should be integrated with that of surplus military plutonium. This article summarizes that work. For references, please see the full report.¹

Plutonium-239 is made by irradiating relatively abundant, naturally-occurring uranium-238 in a nuclear reactor. This can be done for military purposes, whereby plutonium is extracted from the fuel and targets rods that have been irradiated in a nuclear reactor (collectively called the irradiated reactor fuel, or spent fuel). Plutonium is also created in commercial nuclear reactors, since uranium-238 is present in large amounts in commercial nuclear reactor fuel. Since there are a large number of such reactors (more than 400 worldwide), the total quantity of plutonium that has been generated in the commercial nuclear power industry has been far greater than that produced in military nuclear weapons programs. By the end of 1999, the total plutonium created in commercial power reactors amounted to over 1,400 metric tons, compared to about 270 to 300 metric tons in military programs.

Plutonium can also be used to fuel reactors. In order to be used as a nuclear fuel, plutonium must first be separated from residual uranium and fission products in the irradiated fuel rods. The chemical and electrochemical processes used to accomplish that separation go under the general rubric of "reprocessing." Of military plutonium, about 250 metric tons remains in government stocks. The rest was used up in nuclear tests, scattered about the world and in underground cavities, as the unused residue from tests, and stored or dumped as waste. Of the commercial plutonium, about 280 metric tons has been separated, while the rest remains in the spent fuel. Some of the separated commercial plutonium has been used as a mixed plutonium oxide-uranium oxide (MOX) fuel, while the rest is stored. Table 1 shows the current inventory of commercially separated plutonium in the world.

The stock of commercial plutonium is growing at roughly ten metric tons per year, since the amount of plutonium being used as MOX fuel is considerably lower than the amount separated. The military stock is growing at about one metric ton per year, mainly in Russia and the United States, both which claim that they are reprocessing for environmental, not military, reasons. At this rate, the stock of commercial separated plutonium is set to exceed the stock of military plutonium in the next few years. It is already so huge that it represents a serious proliferation problem. An Interagency Working Group of the US government on plutonium disposition has clearly stated that:

One metric ton of weapon-grade plutonium could be used to make about 200 nuclear bombs - more, if sophisticated bomb designs are used. It takes roughly 40 percent more commercial-grade plutonium to make a similar bomb. Stored commercial plutonium is therefore sufficient to make at least 30,000 nuclear bombs of a size similar to the one that destroyed Nagasaki.

For much of the period after World War II, plutonium was viewed not only as the currency of power in a nuclear weapons world, but also as a "magical" energy source. This was because a special type of reactor, called a breeder reactor, would convert uranium-238 into more plutonium-239 than was actually needed to run the reactor. Hence there would be more fuel (plutonium-239) at the end of the process than at the beginning, even though electricity had been generated.³

The high hopes of the 1950s that plutonium would provide such a "magical" energy source - one that might even be "too cheap to meter" - have run aground on the shoals of a host of practical problems that have steadily grown worse over the past 25 years:

1. Uranium turned out to be far more plentiful than anticipated, and the price of uranium declined rapidly (with an upward blip in the 1970s). It is currently at or near historic lows.
2. Sodium-cooled breeder reactors, the technology of choice for creating a plutonium economy, and the one in which the greatest efforts and money have been invested, have turned out to be a very difficult technology to master and make economical. Despite over $20 billion (1999 dollars) in construction expenditures over more than four decades for just the large completed plants, the technology continues to be plagued by technical problems and high costs. Table 2 shows the approximate worldwide capital expenditures on major sodium-cooled breeder reactors (in 1996 dollars), and the current status of the various reactors.
3. Separated commercial plutonium can be used to make nuclear weapons, so that the development of a plutonium economy incurs considerably increased proliferation risks compared to those posed by uranium-fueled nuclear power reactors.
4. Reprocessing proved to be a costly technology, thereby increasing costs of plutonium relative to uranium.
5. Reprocessing results in discharges of large amounts of liquid radioactive waste and also creates other radioactive wastes that pose environmental problems and create safety and health risks.

These structural factors have been accompanied by recent events, all but one of which are highly unfavorable to continued commercial reprocessing and MOX fuel use:

1. After the election of the Social Democratic-Green coalition government in late 1998, Germany decided to phase out nuclear power. This phase-out schedule, as it stands at the present time, will be relatively slow, corresponding approximately to the lifetime of the existing power plants. But the phase-out necessarily includes a stoppage of reprocessing German spent fuel. This will make it even more difficult to rationalize continued operation of UP2 in France (a facility dedicated to foreign spent fuel reprocessing) and the reprocessing plant in Britain, called THORP, belonging to the government-owned company, British Nuclear Fuels (BNFL), also commissioned to serve foreign customers.
2. The German government's decision to phase-out nuclear power, and hence also reprocessing, is causing reverberations in France and elsewhere, where the topic of a phase-out of nuclear power is no longer as politically difficult as before. The subsidies to plutonium in France particularly stick out as a sore thumb. (See accompanying article on French doubts about reprocessing and MOX.)
3. The Science and Technology Committee of the British House of Lords concluded in 1999 that most British commercial plutonium should be declared a waste. This was a severe blow to the prospects for plutonium fuel subsidies in Britain.
4. The sodium-fire accident at the Monju demonstration breeder reactor in Japan in 1995 - only about a year-and-a-half after it went critical - and the September 1999 criticality accident at the Tokaimura plant (which killed two workers from high-level radiation exposure and injured many others) have increased opposition to Japan's MOX fuel use plans. The entire future of nuclear power in Japan is now far more open to question than seemed possible before the Tokaimura accident.
5. The revelation that some BNFL MOX fuel quality control data were fabricated, including data relating to some of the fuel shipped to Japan, has thrown the British MOX program as well as reprocessing into disarray.
6. Russia's Minatom, the nuclear energy agency with the strongest attachment to a plutonium economy, has been and continues to be strapped for funds and cannot pursue an ambitious breeder reactor program on its own. Russia also lacks a commercial-scale MOX fuel fabrication plant.
7. The sole recent factor favoring MOX fuel use comes from the military sector. The 1 September 2000 US-Russian agreement would fill the only gap in the Russian plutonium fuel cycle infrastructure, if it is fully funded by the West and proceeds as envisioned (see below). This agreement is aimed at putting military stocks of plutonium that have been declared surplus by the two countries into non-weapons usable form, mainly by using it as MOX fuel in light water reactors. Russia also wants the MOX fuel fabrication plant to be capable of making MOX fuel for breeder reactors. However, Russia and the United States have not been able to arrive at an agreement about who would bear the liability for the program, including in case of an accident. The agreement leaves that question open for further negotiations. (See accompanying article on the US-Russian plutonium disposition deal.)

The net result of the historical and current trends and events is that there is now a large policy issue of what should be done with the huge but uneconomical stock of commercial plutonium that is growing rapidly. The problem is exacerbated by the fact that the plutonium stocks and facilities are run by institutions that have a declining command of public confidence and respect, not least because of the data fabrication, safety, and environmental scandals that afflict BNFL. These factors have compounded the underlying problems arising from poor economic decision-making by governments and plutonium-related corporations.

Unsurprisingly, the plutonium industry continues to push for subsidies, upon which it should have no reasonable claim. A huge and unjustifiably large sum - on the order of $100 billion worldwide - has already been spent over the past five decades on attempts to create a plutonium economy. Much of this was on large breeder reactors, most of which are now shut. Most of the rest was on reprocessing and the use of the resulting uneconomical plutonium as a reactor fuel. These costs are summarized in Table 3. There is no end in sight to the subsidies and there is no reasonable way to resolve the many problems that are still outstanding in the foreseeable future.

By any rational economic and security criteria, the commercial plutonium fuel and breeder industries should have made a complete exit from the stage of energy choices at least a decade ago. Yet, commercial plutonium separation continues in several countries. Plans for breeder reactors also remain in place in some countries. Use of plutonium as a fuel (in the form of mixed uranium and plutonium oxide or MOX) in existing reactors grew considerably in the 1990s, creating a new set of subsidies for the plutonium industry.

These subsidies and unrealistic plans persist because those who fervently hope and believe in the long-term future of plutonium as an energy source have had enough muscle in the political and economic arenas to keep the plutonium flame alive. Indeed, they have been able to vastly increase the amount of plutonium being separated and used as MOX fuel in light water reactors - the most common kind of commercial reactor - the vast majority of which were not designed for plutonium fuels. In France alone, the use of MOX fuel amounts to a subsidy of about $1 billion per year for the commercial plutonium industry. (See accompanying article on French doubts about reprocessing and MOX.)

The prospects for plutonium fuel have also received a boost from the end of the Cold War. The United States and Russia are proposing to use most of their declared surplus weapons plutonium as a fuel in commercial nuclear power plants. This would provide an immense new subsidy to the plutonium fuel industry, in the name of non-proliferation, and provide the nuclear establishments of both countries with the arguments they need to continue reprocessing and breeder reactor programs. In particular, Minatom, Russia's ministry of atomic energy, has explicit plans to use the infrastructure created with Western non-proliferation funds for its breeder reactor program.

Minatom has explicitly stated that that US-Russian weapons plutonium disposition program "must be seen as the first step in developing a technology for a future closed nuclear fuel cycle..." This would involve "the use of mixed uranium-plutonium fuel of fast reactors" (another name for breeder reactors).⁴ The United States has agreed to such a system in Russia in the context of weapons plutonium, even though it was rejected in the United States in the 1970s as too proliferation prone. (See accompanying article on the US-Russian agreement.)

Converting surplus military weapon-grade plutonium into a fuel and using it in commercial power reactors not only raises proliferation concerns but also concerns related to safety. The vast majority of commercial reactors were designed for uranium, not mixed oxide (MOX) fuel, in which plutonium isotopes provide the fissile material. Modifications to these reactors to accommodate more control elements may be needed. Weapon-grade plutonium has never been used as a commercial fuel in reactors, though plutonium derived from commercial spent fuel is now being used in commercial power reactors in France, Germany, Belgium, and Switzerland. The computer codes that would be used to evaluate the safety of MOX made from weapon-grade plutonium would be those developed for and tested for reactor-grade plutonium. How safety concerns arising from the different plutonium composition of weapon-grade plutonium and reactor-grade plutonium and the different patterns of loading MOX fuel will be resolved remains unclear.

The consequences of an accident in a reactor with MOX fuel would be more severe than one with uranium fuel because MOX fuel contains a larger proportion of plutonium and transuranic radionuclides. The regulatory infrastructure in Russia is relatively weak, leading to questions as to how safety concerns would be brought up or resolved. Moreover, new proliferation risks will also be created, since fresh MOX fuel would be transported on highways and stored at commercial nuclear power plants that do not now have military levels of security.

Even if all plutonium separation in the commercial and military sectors were to stop immediately, there would still remain an immense problem of the management of separated commercial plutonium and surplus military stocks. It is therefore urgent both to stop commercial reprocessing and to create a plan to put separated commercial plutonium and surplus military plutonium into non-weapons-usable form as expeditiously as is consistent with safety, health, and environmental protection.

IEER has shown in previous analyses that immobilization of plutonium in one of several ways would be a safer, faster, and cheaper way to put separated plutonium into non-weapons-usable form.⁵ The primary purpose of this immobilization should be to prevent theft of plutonium by non-nuclear weapons states or terrorist groups. The idea of immobilizing all separated commercial plutonium and all surplus military plutonium has not made progress because of two reasons:

It is generally believed that Russia will not accept any other alternative than to use plutonium as a fuel. Hence the MOX fuel option for surplus military plutonium is seen as essential for putting Russian weapons plutonium into non-weapons-usable form (spent fuel in this case).

The plutonium lobby in the West and Japan has been steadfast in their support of the creation of a MOX fuel infrastructure using non-proliferation funds.

While it is true that Minatom wants western funds to create a MOX fuel infrastructure, this does not mean that a different proposal would be rejected by all parts of Russian society or government. For instance, no offer to purchase all Russian separated commercial plutonium and all surplus weapons plutonium for immobilization and storage in Russia under international safeguards has ever been officially presented to the Russian government. It would cost at most $2 billion for the purchase of 80 metric tons of plutonium, if is valued at its maximum possible theoretical price (that is if it were magically transformed into MOX fuel at zero cost).⁶ It would cost a comparable sum to immobilize the plutonium. Existing cooperative nuclear security arrangements indicate a Russian willingness to consider programs that it would not otherwise have undertaken. Yet no Western offer to purchase Russian surplus plutonium for immobilization has officially been made to the Russian government. Such an approach, coupled with a complete halt to reprocessing all over the world, deserves urgent consideration for non-proliferation, safety and environmental reasons.

6. The actual economic value of plutonium as a fuel (whether of commercial or military origin) is negative since it is more costly than uranium fuel.