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Perspectives

LUTHER J. CARTER

THOMAS H. PIGFORD

Confronting the Paradox in Plutonium Policies

A major threat of nuclear weapons proliferation is to be found in the plutonium from reprocessed commercial fuel.

The world's huge stocks of separated, weapons-usable military and civil plutonium are at present the subject of profoundly contradictory, paradoxical policies. These policies fail to squarely confront the serious risks to the nuclear nonproliferation regime posed by civil plutonium as a fissile material that can be used by rogue states and terrorist groups to make nuclear weapons.

About 100 metric tons of weapons plutonium has been declared surplus to military needs by the United States and Russia and will be converted to a proliferation-resistant form (ultimately to be followed by geologic disposal) if present policy commitments are realized. But no comparable national or international policy applies to the civil plutonium stocks, although these are already more than 50 percent greater than the stocks of military plutonium arising from the dismantling of bombs and warheads.

Most of the separated civil plutonium has been created at commercial fuel reprocessing plants in Britain and France, to which various other countries, especially Germany and Japan, have been sending some of the spent fuel from their commercial uranium-fueled reactors, expecting to eventually use the returned plutonium as reactor fuel. But plans for recycling plutonium as reactor fuel have been slow in maturing, so large inventories of civil plutonium have accumulated.

Risks of separated plutonium

The greatest concentration of civil plutonium stocks is at the nuclear fuel reprocessing centers in France at La Hague, on the English Channel; and in Britain at Sellafield, on the Irish Sea. The total for all French and British civil stocks, at the reprocessing centers and elsewhere, is over 132 tons, part of it held for utilities in Germany, Japan, and other countries. Russia's stock of about 30 tons is the third largest, nearly all of it stored at the reprocessing plant at Chelyabinsk, in the Urals. Smaller but significant stocks of plutonium are present in Germany, Japan, Belgium, and Switzerland, converted in considerable part to a mixed plutonium-uranium oxide fuel called MOx, now waiting to be used in designated light water reactors. The recycling of plutonium in breeder reactors is quite different technology from that found in light water reactors, and commercial development of breeders has been beset by repeated economic and technical reverses that have left the future of breeders very much in doubt. In the United States, early ventures in fuel reprocessing, plutonium recycling, and commercial breeder development all came to an end by the late 1970s and early 1980s. But several tons of separated civil plutonium remain in this country from the early reprocessing effort.

According to estimates by the International Atomic Energy Agency (IAEA), total global civil stocks of separated plutonium may exceed 250 tons by the year 2010. The stakes will continue to be enormous for keeping the separated civil and military plutonium secure and well guarded against intrusions by outsiders and malevolent designs by insiders. Granted, there are national and IAEA safeguards for closely accounting for and protecting all separated plutonium and fresh MOx. We believe that these safeguards reduce the risk of plutonium diversions, thefts, and forcible seizures to a low probability. But in our view the risk is still too great in light of the horrendous consequences of failure.

Separated plutonium could become a target for theft or diversion by a subnational terrorist group, possibly one assisted by a rogue state such as Iraq or North Korea. Less than 10 kilograms of plutonium might suffice for a crude bomb small enough to be put in a delivery van and powerful enough to explode with a force thousands of times greater than that of the bomb that destroyed the federal building in Oklahoma City.

The risk posed by separated plutonium has partly to do with the possibility of diversions for weapons use by a nation whose utilities own the plutonium. Indeed, the potential for such a diversion by a state that has a store of plutonium could increase over time. Even a respected nonnuclear-weapons state, such as Japan, might at some future time feel coerced by new and threatening circumstances to break with the nonproliferation regime and exploit its civil plutonium to make nuclear weapons.

But the greater and more immediate problem is the risk of theft or diversion by terrorists, and that risk lies chiefly in the circulation of plutonium within the nuclear fuel cycle. The many different fuel cycle operations, such as shipping, blending with uranium, fabrication into fresh MOx, storage, and further shipping, all provide opportunities for diversion. A plutonium disposition program will therefore be less than half a loaf unless accompanied by a commitment to end all further separation of plutonium.

An industrial disposition campaign

In less than two decades from start up of the campaign, the nuclear industries of France and Britain could convert virtually the entire global inventory of separated civil plutonium and half the surplus military plutonium to a proliferation-resistant form. But this would mean ending all civil fuel reprocessing and, with the completion of the plutonium conversion campaign, ending all plutonium recycling as well.

For the French and British nuclear industries to embrace so profound a change would mean a marked shift in policy by government as well as industry, for in France the nuclear industry is wholly government-owned and in the United Kingdom British Nuclear Fuels is a national company. The change in government policy in those two countries could be achieved only with the cooperation of key governments abroad--especially the governments of the United States, Russia, Germany, and Japan--and of foreign utilities that own significant amounts of plutonium.

In addition, there would have to be a growing demand for safe plutonium disposition around the world: by political leaders and their parties, by environmental and safe-energy groups, and by the peace groups, policy research groups, and international bodies that together make up the nuclear nonproliferation community. Essential to all the foregoing will be a keen awareness of the proliferation risks associated with separated plutonium and of the possibilities for safely disposing of that plutonium.

We believe that a plutonium disposition campaign relying mostly on nuclear facilities already existing in Britain and France could be carried out far more quickly than would be possible for campaigns elsewhere requiring the construction or modification of whole suites of industrial plants and reactors. Indeed, disposition of Russia's surplus military plutonium alone is expected to depend on construction of a new MOx fuel plant that the major industrial countries will almost certainly be called upon to pay for.

The United States, where much development work has been done on plutonium disposition, will most likely continue with its own program for disposition of surplus U.S. military plutonium. But the French and British should be encouraged to assume a major, indeed dominant, role in the disposition of Russia's surplus military plutonium as well as in the disposition of the world's stocks of separated civil plutonium.

The French-British campaign could be expected to squarely meet what the United States and Russia have decided on (with approval by the major industrial countries, or "G-8") as the standard appropriate for safe disposition of surplus U.S. and Russian military plutonium. The standard agreed to was first adopted by the U.S. Department of Energy (DOE) on the recommendation of the National Academy of Sciences' (NAS's) Committee on International Security and Arms Control (CISAC). Known as the "spent fuel standard," it represents a rough measure of the proliferation resistance afforded by the obstacles that spent fuel presents to plutonium recovery, namely its intense radioactivity, its great mass and weight, and its requirement for remote handling. The obstacles referred to are very real, especially for any party lacking the resources of a nation-state.

The job ahead

In meeting the spent fuel standard, the United States plans to have its surplus military plutonium disposition program proceed along two tracks. On one track, plutonium will be converted to MOx to be used in certain designated reactors and thereby rendered spent. On the other track, plutonium will be immobilized by incorporating it in massive, highly radioactive glass logs. In DOE parlance, the two tracks are the "MOx option" and the "immobilization option." Ultimately, after repositories become available, the spent MOx and the radioactive glass logs would be placed in deep geologic disposal.

We must create a global network of internationally sanctioned centers for storage and disposal of spent fuel.

The MOx and immobilization options are clearly within the capabilities of the nuclear industry in France and Britain. The MOx option offers the more immediate promise. MOx fuel manufacturing capacity in France and Britain (together with some in Belgium) will soon rise to approximately 350 tons of MOx production a year, which is more than enough for an intensive and expeditious plutonium disposition campaign. The MOx fuel plants are either operating already or are built and awaiting licensing to receive civil plutonium.

Further, Electricité de France has designated 28 of its reactors to operate with MOx as 30 percent of their fuel cores, and of these, 17 already are licensed to accept MOx. With all 28 reactors in use, half of the world inventory of 300 tons of separated civil plutonium and surplus non-U.S. military plutonium expected by the year 2010 could be converted to spent MOx in about 17 years (we exclude here the 50 or so tons of U.S. military plutonium that the United States will dispose of itself). The fresh civil MOx going into the reactors (we assume a plutonium content of 6.6 percent) would be easily handled because it emits relatively little external radiation; but the spent MOx coming out of the reactors would be intensely radioactive and present a significant barrier to plutonium diversion. The spent MOx would not be reprocessed but rather marked for eventual geologic disposal.

The immobilization option, as thus far developed in the United States, is not as well defined as the MOx option. Now favored by DOE is a "can-in-canister" concept that is still under technical review. The plutonium would be imbedded in ceramic pucks that would be placed in cans arrayed in a latticework inside large disposal canisters. Molten borosilicate glass containing highly radioactive fission products would be poured into these canisters.

At DOE's request, an NAS panel is currently reviewing the can-in-canister design to judge whether it does in fact meet the spent fuel standard. Experts from the national laboratories have, for instance, offered conflicting views about whether terrorists using shaped explosive charges might quickly separate the cans of plutonium pucks from the radioactive glass. The NAS review panel awaits further studies, including actual physical tests, to either approve the present design or arrive at a better one.

Yet despite the uncertainties, immobilization remains an important option, to be carried out in parallel with the MOx option or, as some advocate, to be chosen in place of the MOx option. Immobilization does not entail the security problems that come from having to transport plutonium from place to place. In the MOx option, by contrast, there is a risk in transporting plutonium from reprocessing centers to MOx factories and in transporting fresh MOx to reactors. We see this risk as acceptable only because the MOx program would be completed in less than two decades and then be shut down.

If DOE can arrive at an acceptable immobilization design, the French and British could no doubt come up with an acceptable design of their own, either a variant of the can-in-canister concept or, perhaps better, a design for a homogeneous mixture of plutonium, glass, and fission products. Cogema, the French nuclear fuel cycle company, has at La Hague two industrial-scale high-level waste vitrification lines now operating and another on standby. British Nuclear Fuels Limited (BNFL) has a similar line of French design at Sellafield. Earlier we noted that with the MOx option, half of the 300-ton plutonium inventory expected by the year 2010 could be disposed of by the French and British in about 17 years; disposing of the other half by immobilization could also take about 17 years. There are not yet sufficient data to compare the costs of the MOx and immobilization options.

The nuclear industry's future

For the nuclear industry in France and Britain, a commitment to such a plutonium disposition campaign and to ending fuel reprocessing and plutonium recycling would be truly revolutionary. It would mark a sea change in industry thinking about plutonium and proliferation risks--not just in these two countries, but far more widely.

With development of an economic breeder program proving stubbornly elusive, plutonium simply cannot compete as a nuclear fuel on even terms with abundant, relatively inexpensive, low-enriched uranium. In hindsight it seems clear that use of plutonium fuel abroad has depended more on government policy and subsidy than on economics. And politically, plutonium has been only a burden, at times a heavy one. In Germany in the early to mid 1980s, protesters came out by the thousands to confront police in riot gear at sites proposed for fuel reprocessing centers (which as things turned out were never built). For the nuclear industry worldwide, and even in France and Britain, it is vastly more important to find solutions to the problems of long-term storage and ultimate disposal of spent fuel than to sustain a politically harassed, artificially propped-up, fuel reprocessing and plutonium recycling program.

Worldwide there are about 130,000 metric tons of spent fuel, about 90,000 tons of it stored at 236 widely scattered nuclear stations in 36 different countries, the rest stored principally at spent fuel reprocessing centers and at special national spent fuel storage facilities such as those in Germany and Sweden. Of the approximately 200,000 tons of spent fuel generated since use of civil nuclear energy began, only 70,000 tons have been reprocessed. This gap promises to continue, because although about 10,000 tons of spent fuel are now being generated annually, the world's total civil reprocessing capacity is only 3,200 tons.

Spent fuel has a curious dual personality with respect to proliferation risks. On the one hand, as made explicit by the formally ordained spent fuel standard, spent fuel is inherently resistant to proliferation because of its intense radioactivity and other characteristics. But uranium spent fuel contains about 10 kilograms of plutonium per ton, and the approximately 1,100 tons of recoverable plutonium in the present global inventory of spent fuel is about four times the amount that was in the arsenals of the United States and the Soviet Union at the peak of the nuclear arms race.

As CISAC has recognized, meeting the spent fuel standard will not be the final answer to the plutonium problem, because recovery of plutonium from spent fuel for use in nuclear explosives is possible for a rogue state such as Iraq or North Korea and even for a terrorist group acting with state sponsorship. Accordingly, the nuclear nonproliferation regime cannot be complete and truly robust until storage of nearly all spent fuel is consolidated at a relatively few global centers, the principal exception being fuel recently discharged from reactors and undergoing initial cooling in pools at the nuclear power stations. But what is particularly to the point here is that the nuclear industry will itself be incomplete until a global system for spent fuel storage and disposal exists, or at least is confidently begun. Without such a system, the nuclear industry will be in a poor position to long continue at even its present level of development, much less aspire to a larger share in electricity generation over the next century.

A lack of government urgency

Not the slightest beginning has been made in establishing the needed global network of centers for long-term storage and ultimate disposal of spent fuel. No country is close to opening a deep geologic repository even for its own spent fuel or high-level waste, quite aside from opening one that would accept such materials from other countries. A common and politically convenient attitude on the part of many governments has been to delay the siting and building of repositories until decades into the future. Under the IAEA, an international convention for radioactive waste management has been adopted; but although this may result in greater uniformity among nations with respect to standards of radiation protection for future people, the convention does not mention, even as a distant goal, establishing a global network of storage and disposal centers available to all nations.

The United States has the most advanced repository program, yet it is a prime case in point with respect to a lack of urgency and priority. Yucca Mountain, about 100 miles northwest of Las Vegas, Nevada, has long been under investigation as a repository site. But Congress lets this program poke along underfunded. This past fiscal year, more than $700 million went into the Nuclear Waste Fund from the user fee on nuclear electricity, yet rather than see all this money go to support the nuclear waste program, Congress chose to have about half of it go to federal budget reduction. The Yucca Mountain project received $282.4 million.

The time may be propitious for stopping or rapidly phasing out fuel reprocessing.

The Yucca Mountain repository is scheduled to be licensed, built, and receiving its first spent fuel by the year 2010, but as matters stand this will not happen. Even the promulgation of radiation standards for the project has languished from year to year. A delay in opening the repository would not itself be troubling if the government would adopt a policy of consolidating surface storage of spent fuel near the Yucca Mountain site. In fact, we have repeatedly urged adoption of such a policy, one benefit being that it would allow all the time needed for exploration of Yucca Mountain and for development of a repository design that meets highly demanding standards of containment.

But little progress has been made on this front either, and spent fuel continues to accumulate at the more than 70 U.S. nuclear power stations, threatening some of them with closure. The state of Minnesota, for instance, limits the amount of storage onsite at Northern States Power's Prairie Island station. Also, the wrong example is being set from the standpoint of the nuclear nonproliferation regime. In our view, consolidated storage at a limited number of internationally sanctioned sites, with greater central control over spent fuel shipments and inventories, should be the universal rule.

One might think that opponents of nuclear energy, especially among the activists who make it their business to probe nuclear programs for weaknesses, would be deploring the lack of consolidated spent fuel storage. But neither the activists here in the United States nor those in Europe are doing so. Indeed, as part of their strategy for stopping work at Yucca Mountain, the U.S. activists insist that all spent fuel remain at the nuclear stations, for the next half century if need be. For them, the unresolved problem of long-term storage and ultimate disposal of nuclear waste should be left hanging around the neck of the nuclear enterprise in order to hasten its demise. Activists acknowledge that sooner or later safe disposal of such waste will be necessary, but in their perspective the radiation hazards are for the ages and what is urgent is to shut down nuclear power. The nonproliferation regime and the need to strengthen it don't enter into these calculations. But the plutonium in spent fuel poses risks not just for the ages but right now. Rogue states and terrorists are here with us today.

What is needed is to have the safe disposition of plutonium become a central and widely understood rationale for the storage and disposal of spent fuel and high-level waste. In disposition of separated civil and military plutonium the final step would be geologic disposal of the spent MOx and canisters of radioactive glass. This would occur along with disposal of spent uranium fuel containing the vastly larger amount of plutonium in that fuel. The 47 kilograms of civil plutonium contained in every ton of spent MOx is nearly five times the 10 kilograms contained in a ton of spent uranium fuel, but even the latter is enough for one or two nuclear weapons. Accordingly, geologic disposal of spent fuel would be needed for a robust nonproliferation regime even if no plutonium had ever been separated.

Creating a global network of internationally sanctioned centers for storage and disposal of spent fuel and high-level waste storage and disposal centers has a powerful rationale on these grounds alone, and it is a rationale that needs to be clearly recognized.

An opportunity for industry

The nuclear industry in the United States, France, Britain, and around the world should be working determinedly to make policymakers, editorial writers, and society at large understand what is at stake. This is the most effective thing the industry can do to promote a political sea change with respect to acceptance of plans for spent fuel storage and disposal that are vital to nuclear power's survival. But proclaiming a concern for strengthening the nonproliferation regime will ring hollow if, as in France, the further separation and recycling of plutonium are to continue and indeed expand. The MOx cycle now planned by the French would have a working level of plutonium of about 23 tons circulating through the system, either in its separated form or as fresh MOx.

The nuclear industry, especially in Europe, Russia, and Japan, must rethink its old assumptions and demonstrate in dramatic fashion its concern to ensure a technology that is far less susceptible to abuse by weapons proliferators. We see an attractive deal waiting to be struck: The nuclear industry gives up civil fuel reprocessing and plutonium separation and volunteers to assume a central role in the safe disposition of all separated plutonium, civil and military alike. In return, the governments of all nations that are able to help (not least the United States) would commit themselves to creating the global network of centers needed for storage and disposal of spent fuel and high-level waste. Underlying such a deal must be a wide societal and political understanding that to let things continue indefinitely as they are will present an unacceptable risk of eventual catastrophes.

Leaders of the nuclear enterprise, after sorting out their thinking among themselves, might propose an international conference of high officials from government, the nuclear industry, and the nonproliferation regime. This conference, addressing the realities of plutonium disposition and spent fuel storage and disposal, would try to agree on goals, the preparation of an action plan, and an appropriate division of responsibilities. Such a conference, if successful, could create a new day for nuclear energy.

One might, for instance, see a new urgency and priority on the part of the U.S. Congress and White House with respect to providing both consolidated national storage of spent fuel and a geologic repository capable of protecting future people from dangerous radiation and from recovery of plutonium for use as nuclear explosives. The United States might agree even to accept at least limited amounts of foreign spent fuel when this would achieve a significant nonproliferation objective. A similar response to the new international mandate could be expected from other countries.

Time to end reprocessing

In the 1970s, two U.S. presidents, Gerald Ford (a Republican) and Jimmy Carter (a Democrat), moved to withdraw government support for commercial reprocessing and plutonium recycling because of the proliferation risks. President Carter urged other countries to follow the U.S. lead and go to a "once-through" uranium fuel cycle, with direct geologic disposal of spent fuel. But the French and British reprocessors, unmoved by the U.S. initiative, continued on their own way, and many foreign utilities (especially in Germany and Japan) were eager to enter into contracts, for the national laws or policies under which they operated either favored reprocessing or insisted upon it.

But circumstances today are quite different. Some individuals of stature within the reprocessing nations themselves are showing a new attitude. In February 1998, the Royal Society of the United Kingdom Academy of Science, in its report Management of Separated Plutonium, found "the present lack of strategic direction for dealing with civil plutonium [to be] disturbing." The working group that prepared the report included several prominent figures from Britain's nuclear establishment, including the then chairman of the British Nuclear Industry Forum and a former deputy chairman of the United Kingdom Atomic Energy Authority. Although cautious and tentative in thrust, the report suggested, among other possibilities, cutting back on reprocessing.

Economically, too, the time may be propitious for stopping or rapidly phasing out reprocessing. Under the original 10-year baseload contracts for the reprocessing to be done at the new plants at Sellafield and La Hague, all the work was paid for up front, leaving these plants fully amortized from the start. With fulfillment of the baseload contracts now only a few years off, BNFL and Cogema are a long way from having their order books filled with a second round of contracts. In an article on December 10, 1998, Le Monde reported that if German utilities, under the dictates of government policy, withdraw from their post-baseload contracts, Cogema would either have to shut down UP-3 (the plant built to reprocess foreign fuel) or operate it at reduced capacity and unprofitable tariffs.

On the other hand, if the French and British nuclear industries were to undertake an intensive campaign for safe disposition of plutonium, they would surely receive fees and subsidies ensuring an attractive return on their investment in MOx fuel plants and high-level-waste vitrification lines.

The United States should proceed with all deliberate speed to establish a center for storage and disposal in Nevada.

Another reason why reprocessing nations should reexamine their belief in plutonium recycling is that past claims for waste management benefits from such recycling are, on close examination, overstated or wrong. For instance, the National Research Council's 1995 report Separations Technology and Transmutation Systems points out that in a geologic repository the long-term hazards from contaminated ground water will be created mainly from fission products, such as technetium-99, and not from plutonium. Discharged MOx fuel will contain no less technetium than spent uranium fuel and will contain more iodine-129. Recycling fission products, along with plutonium and other transuranics, could theoretically benefit waste management, but only after centuries of operation and at the expense of more complicated and costly reprocessing.

As a possible longer-term option for plutonium disposition, France has described a MOx system that would also include a suite of 12 fast reactors deployed as plutonium burners. In this scenario, which assumes that the formidable costs of fast reactors and their reprocessing facilities are overcome, all spent fuel would be reprocessed and its plutonium recycled. But the substantial inventory of plutonium would be daunting. About 10 tons of plutonium would be needed to start up each fast reactor, or 120 tons altogether. Most of that would remain as inventory in the system. Further, the two-year working inventory of separated plutonium and fresh plutonium fuel needed by the 12 reactors would be about 50 tons. The potential here for thefts, diversions, and forcible seizures of plutonium is undeniable.

Creating the global network of centers

Under the best of circumstances and with the strongest leadership, creating a global network of storage and disposal centers for spent fuel and high-level waste will still be an extraordinary challenge. But the job is not undoable provided certain critical conditions are met.

Of overriding importance is that one of the major nuclear countries establish a geologic repository at home, inside its own boundaries. Unless this is done, the very concept of international centers falls under the suspicion that what's afoot is an attempt by the nuclear countries to dupe countries with no nuclear industry into taking their waste. And if the proposed recipient nation should be a poor country desperate for hard currency, the whole thing looks like a cynical and egregious bribe. What this all points up is that the United States should proceed with all deliberate speed to establish a center for storage and disposal in Nevada. No other country is in a position to take the lead in this.

Once this condition is satisfied, then to offer strong economic incentives to potential host countries should become not only acceptable but expected, because the service proposed is one that should demand high compensation. The Russian Duma, for instance, might look more favorably on current proposals for storage of limited amounts of foreign spent fuel in Russia, especially knowing that part of the revenue therefrom can go toward establishing Russia's own permanent geologic repository.

Let's take Australia as another example. An advanced democratic society in the Western tradition, Australia is a major producer of uranium but has no nuclear power industry of its own. Beyond its well-populated eastern littoral is a vast desert interior, from which in the main the nation gets only very limited economic benefits. Pangea Resources, a Seattle-based spinoff of Golder Associates of Toronto, has been circulating a plan for a repository that would be built somewhere in the West Australian desert.

In this venture, Pangea has received substantial financial backing from British Nuclear Fuels and the Swiss nuclear waste agency. Until now, Australia's attitude has been thumbs down, but that attitude might change if the United States should create in Nevada a repository that could be a prototype for repositories on desert terrain around the world, and if at the same time the Australians knew they would be doing their part toward strengthening the nuclear nonproliferation regime.

It's not often that a single commercial enterprise is presented with the chance to bring about, on a global scale, an enormous improvement in its own fortunes and at the same time strengthen a regime vital to the protection of society. But just such a chance is now at hand for the civil nuclear industry. If it fails to take it, the consequences may be the industry's gradual decline, perhaps even its ruin, and the continuation of a grave danger to us all.

Recommended reading

D. Albright et al., Plutonium and Highly Enriched Uranium 1996: World Inventories, Capabilities, and Policies. Oxford, U.K.: Oxford University Press for the Stockholm International Peace Research Institute, 1997.

Richard L. Garwin, "Reactor-Grade Plutonium Can Be Used to Make Powerful and Reliable Nuclear Weapons...," August 26, 1998, http://www.fas.org/rlg/980826-pu.htm.

J. Lochard et al., "Safety, Health and Environmental Implications of the Different Fuel Cycles," Key Issue Paper No. 4, Proceedings of the International Symposium on Nuclear Fuel Cycle and Reactor Strategy: Adjusting to New Realities, pp. 199-235, International Atomic Energy Agency, 1997.

National Academy of Sciences, Committee on International Security and Arms Control, Management and Disposition of Excess Weapons Plutonium, Washington, D.C.: National Academy Press, 1994.

National Academy of Sciences, Committee on International Security and Arms Control, Management and Disposition of Excess Weapons Plutonium: Reactor-Related Options, Washington, D.C.: National Academy Press, 1995.

National Academy of Sciences, Committee on International Security and Arms Control, Interim Report of July 1999 by the CISAC panel on MOx/Immobilization Assessment, (in progress).

National Research Council Committee on Separations Technology and Transmutation Systems, N.C. Rasmussen et al., Nuclear Wastes: Technologies for Separations and Transmutation, Washington, D.C.: National Academy Press, 1996.

Luther J. Carter and Thomas H. Pigford, "The World's Growing Inventory of Civil Spent Fuel," Arms Control Today, January/February 1999, pp. 8-14.

Luther J. Carter and Thomas H. Pigford, "Getting Yucca Mountain Right," The Bulletin of the Atomic Scientists, March/April 1998, pp. 56-61.


Luther J. Carter (lcarter345@aol.com) is a writer in Washington, D.C., and author of Nuclear Imperatives and Public Trust: Dealing with Radioactive Waste. Thomas H. Pigford (pigford@nuc.berkeley.edu) is a professor of nuclear engineering at the University of California at Berkeley and coauthor of Nuclear Chemical Engineering.