TESTIMONY OF PAUL LEVENTHAL
President, Nuclear Control Institute
on Reprocessing, Waste and Non-Proliferation
Presented to a Parliamentary Hearing of the Tweede Kamer
The Hague, The Netherlands
October 24, 1997
My name is Paul Leventhal. I am president and founder of the Nuclear Control Institute (NCI), a nuclear non-proliferation research and advocacy center in Washington, D.C. NCI seeks to increase understanding of security risks associated with civilian uses of nuclear-weapon materials---plutonium and highly enriched uranium---and develops strategies for avoiding and eliminating their use. I appreciate your invitation to present testimony today on decisions facing the Dutch government on reprocessing of spent nuclear fuel and on associated waste management and proliferation problems. Steven Dolley, NCI research director, and Edwin Lyman, NCI scientific director, assisted in the preparation of this testimony.
Three years ago, Parliament determined that the Netherlands should phase out its nuclear power program. This decision has resulted in the permanent closure of the Dodewaard reactor this past March, and the planned shutdown of the Borssele reactor by 2004. Now the Dutch people are confronted with a dilemma: how to dispose of unwanted plutonium and the associated highly radioactive waste from the reprocessing of spent fuel of these reactors?
The Netherlands decided almost 30 years ago to enter into contracts for the reprocessing of Dutch spent fuel by COGEMA in France and British Nuclear Fuels Ltd. (BNFL) in Great Britain. Times were very different then. The nuclear industry anticipated that rapid growth in the number of nuclear-power stations worldwide would quickly outstrip the ability to produce large amounts of affordable uranium fuel. Industry expected that nuclear power programs would move to a "closed fuel cycle" in which spent uranium fuel would be reprocessed to separate out plutonium, a man-made element created in reactors for use either in reactors or in bombs. The recovered plutonium would fuel fast-breeder reactors (FBRs). These breeders would produce more plutonium than they consumed, and create unlimited amounts of inexpensive energy---electricity "too cheap to meter."
But this plutonium dream began to fall apart as the assumptions undergirding it began to fall away. High capital costs and safety concerns caused many nations, including the Netherlands, to scale back dramatically their nuclear-power development plans. At the same time, uranium turned out to be far more abundant than anticipated, and the price of this commodity began to decline steadily as the market became oversupplied. The costs of reprocessing spent fuel and fabricating plutonium into a uranium-plutonium, mixed-oxide (MOX) fuel soared. The breeder reactor proved to be far costlier, more difficult to develop, and more dangerous to operate than originally assumed. Medical research established that plutonium was one of the most potent carcinogens known---a speck, a few millionths of a gram, sufficient to cause lung or bone cancer. But the greatest risk was plutonium's weapons potential---only a few kilograms of plutonium are sufficient to build a nuclear bomb with the explosive power to destroy a city.
This reversal of fortune for plutonium has been reflected in the demise of breeder- reactor programs in major industrial states. Germany and Great Britain have canceled their breeder programs. France decided to operate its commercial-scale Superphenix FBR as an experimental plutonium "burner" rather than a breeder, but safety problems have barred issuance of a license even for that purpose, and the French environment minister recently announced plans to shut down the reactor permanently.1 As a result, the project to develop a European FBR---the primary raison d'etre for Dutch reprocessing---is all but dead. Japan is now seriously reassessing its own commitment to the breeder and plutonium in the wake of significant accidents at its experimental Monju FBR and Tokai reprocessing plant. The United States canceled its commercial Clinch River Breeder Reactor in 1983 and its Advanced Liquid Metal Reactor breeder project in 1994 because of the economic folly and proliferation and terrorism risks of the plutonium fuel cycle.
The Dutch Government now must decide what is to become of the plutonium produced in Dutch reactors, most of it already separated from spent fuel, some of it not. It must realign its nuclear-waste policy to the demise of the breeder, to the severe diseconomics of using MOX fuel in existing reactors, and to the grave security risks of the plutonium fuel cycle. The key to this realignment process is in the contracts to reprocess Dutch spent fuel.
These contracts currently cover all fuel that has been, and is anticipated to be, discharged by the Dodewaard and Borssele reactors throughout their operational lifetimes. Contracts with COGEMA in France total 219 tonnes of spent fuel through 2002, of which about 160 tonnes have already been reprocessed. Contracts with BNFL for reprocessing at the THORP plant amount to 53 tonnes.2 Given THORP is still in the process of scaling up to full commercial capacity, it is assumed that very little or none of the Dutch spent fuel in Great Britain has yet been reprocessed.
If the British and French contracts are carried out, the Netherlands will be responsible for a cumulative total of over two tonnes of separated plutonium by the turn of the century.3 As partners in the Kalkar project (an FBR constructed in Germany but never operated) and the Superphenix, the Netherlands will also be responsible for disposal of its share of the fuel from these reactors.
The options now under consideration for this spent fuel and separated plutonium are seriously flawed. I will now review each option briefly and then explore the desirable alternatives.
Reacting to large surpluses of separated plutonium that are being generated by spent- fuel reprocessing programs, a few nations, especially France, Germany and Switzerland, have begun limited use of plutonium-uranium, mixed-oxide (MOX) fuel in their light-water reactors (LWRs). Japan is planning such a program. But most LWRs around the world, including Dodewaard and Borssele, continue to utilize low-enriched uranium (LEU) fuel, which unlike plutonium is unsuitable for nuclear weapons.
Should the Netherlands Use Mixed-Oxide (MOX) Fuel?
MOX fuel does not represent a desirable solution to the Dutch plutonium problem for several reasons. First, and most simply, there will most likely be no nuclear reactors operating in the Netherlands after 2004, and hence no capacity to irradiate such fuel. Any Dutch decision to use MOX fuel would require extending the operation of Borssele well beyond its 2004 shutdown. The misguided approach of attempting to irradiate over two tonnes of plutonium in the form of MOX fuel would push back Borssele's shutdown date to the year 2015 at the earliest.
In addition, MOX is expensive---about four to eight times more costly than LEU, according to our calculations.4 In fact, such fuel is so expensive that the French-German European Power Reactor (EPR) project to develop an advanced light-water reactor recently proposed that MOX fuel not be used, in an attempt to make the reactor design economically competitive---despite the pro-MOX posture of Electricite de France (EDF), France's electric utility and one of the project's partners.5
The use of MOX fuel in light-water reactors also increases the risks to the public from nuclear power generation. In particular, because of the greater concentrations of toxic radioactive isotopes such as plutonium, americium and curium in a reactor operating with MOX fuel compared with one operating on LEU fuel, the consequences for public health of a core-meltdown accident would be greater.
Four times as many fatal cancers would result from the passage of the initial radioactive plume from a severe accident involving a reactor with a full core of reactor-grade MOX fuel than from a similar accident involving a low-enriched uranium core, according to a study now being prepared by the Nuclear Control Institute, using computer software developed by the U.S. Nuclear Regulatory Commission. For plants in Europe using MOX in only one-third of the core (which is typical of present practice, although some advanced reactors are being designed to use a full core of MOX), the number of cancers would be twice as great.
For the most severe accidents, under worst-case assumptions there would be tens to hundreds of thousands of additional cancers. For this reason, the Dutch Government should not consider the use of MOX fuel, and it also should question the use of MOX in nuclear power plants in neighboring countries, such as Belgium and Germany. Use of MOX fuel could increase the radiological consequences of an accident at distances hundreds of kilometers from the reactor site, and these consequences would be devastating in a small, densely-populated country such as the Netherlands.
There are also severe security risks involved in the manufacture and use of MOX fuel. MOX is made by mixing plutonium oxide with uranium oxide, and fabricating the mixture into small ceramic pellets that are loaded into metal rods and formed into fuel assemblies for nuclear power plants. This is a messy process, involving bulk handling of plutonium powder by the ton. Making accurate inventory measurements of weapon-usable plutonium in MOX fuel fabrication plants---where plutonium dust sticks to surfaces and shavings and scrap must be collected for recycling---has proven impossible.
There is clear evidence of this problem. In May 1994, the Nuclear Control Institute disclosed that a major plutonium inventory discrepancy had been building up at Japan's pilot MOX fabrication plant since a new automated line began operating in 1988.6 The Japanese government had asserted that this plutonium, amounting to about 70 kilograms, or more than enough for eight nuclear bombs, was not missing because it had been measured as "hold-up" material---that is, as plutonium that stuck to surfaces and got held up in the plant's process equipment. But such measurements were taken indirectly by assaying devices, and were subject to significant uncertainties---as large as 30 percent in some instances.
To deal with the uncertainty, the International Atomic Energy Agency (IAEA) required Japan to cut open the glove boxes and physically produce and measure the held-up plutonium so that inspectors could verify the plant's inventory. At a reported cost of more than US $100 million, and after more than two years of clean-out operations, about 10 kilograms of plutonium (more than a bomb's worth) is still unaccounted for. Japan thus still fails to meet the safeguards criteria required by the IAEA. Plutonium scrap is also a significant source of measurement uncertainty at the Japanese MOX fabrication plant. Scrap containing about 100 to 150 kilograms of plutonium has been put into cans, but the actual plutonium content still must be verified before the inventory balance of the plant can be closed.
MOX fabrication plants in Europe, which would be the likely supplier of MOX fuel for the Netherlands, have not disclosed the operating history of their material control and accounting systems (which are under the control of EURATOM, rather than IAEA). The IAEA is unable to oversee EURATOM safeguards at these facilities and therefore declines to make any judgement about the effectiveness of material accounting and control at European MOX plants.
There is also the crucial question of safeguarding fresh MOX fuel in storage at reactor sites. Weapon-usable plutonium can be separated from fresh MOX fuel by straightforward chemical means. For this reason, the U.S. National Academy of Sciences recommended that fresh MOX fuel be provided the same degree of security accorded to nuclear weapons.7
The adequacy of EURATOM safeguards over MOX fuel at reactor sites is open to question. Indeed, IAEA safeguards director Bruno Pellaud complained to the IAEA director general last year that the IAEA was being denied access to MOX fuel at a reactor site in Germany and being asked to accept EURATOM verification solely on faith.8
Many MOX proponents emphasize that so-called "reactor-grade" plutonium (the plutonium recovered from nuclear power plant fuel by reprocessing) is of a different isotopic composition than so-called "weapons-grade" plutonium (the sort of plutonium created in nuclear-weapon states in military production reactors for use in nuclear weapons). But it is inappropriate to assess proliferation risks by this criterion because it perpetuates a dangerous myth that reactor-grade plutonium cannot be used to make workable weapons.
In fact, the ability to construct a weapon from reactor-grade plutonium was demonstrated decades ago. It is dangerous even to consider it an open question. In 1990, Hans Blix, director-general of the IAEA, informed our Institute that there is "no debate" on this point in the Safeguards Department of the IAEA, and that the agency considers virtually all isotopes of plutonium, including high burn-up reactor-grade plutonium, to be usable in nuclear weapons.9 The U.S. government had declassified information on the weapons utility of reactor-grade plutonium for the IAEA and foreign governments two decades earlier. In June 1994, U.S. Energy Secretary Hazel O'Leary declassified further details of a 1962 test of a nuclear device using reactor-grade plutonium, which successfully produced a nuclear yield.
A recent non-proliferation assessment by the U.S. Department of Energy offered this definitive statement of the problem:
At the lowest level of sophistication, a potential proliferating state or subnational group using designs and technologies no more sophisticated than those used in first-generation nuclear weapons could build a nuclear weapon from reactor-grade plutonium that would have an assured, reliable yield of one or a few kilotons (and a probable yield significantly higher than that). At the other end of the spectrum, advanced nuclear weapons states such as the United States and Russia, using modern designs, could produce weapons from reactor-grade plutonium having reliable explosive yields, weight, and other characteristics generally comparable to those of weapons made from weapons-grade plutonium....In short, reactor-grade plutonium is weapons-usable, whether by unsophisticated proliferators or by advanced nuclear weapon states. Theft of separated plutonium, whether weapons- grade or reactor-grade, would pose a grave security risk.10
Even if the Netherlands took the misguided MOX path, the MOX fuel still would require disposal after irradiation. Because MOX fuel contains much more plutonium than LEU fuel, it produces considerably more heat in the long run, possibly complicating final disposal in a geological repository.
Some in the Dutch government have been operating on the assumption that the Netherlands will be able to sell its separated plutonium to the nuclear utilities of other European nations. The May 1997 report prepared by Energieonderzoek Centrum Nederland (ECN, the Netherlands Energy Research Foundation), for instance, makes this assertion.
Should the Netherlands Sell or Give Away Its Plutonium?
Some Dutch plutonium, recovered by reprocessing under early contracts, was provided for fuel for the Kalkar FBR (174 kilograms) and for fuel for the Superphenix FBR (486 kilograms). As noted earlier, the Kalkar FBR project was cancelled before the reactor ever operated, and Superphenix faces permanent shutdown. A much smaller amount of plutonium (4 kilograms) was sold in 1972 to Belgonucleaire for testing. Worldwide, an enormous glut of civilian separated plutonium is building up and is projected conservatively to reach a surplus of 92 tonnes by the year 2000.11
Today, there is no buyers' market for separated plutonium for commercial purposes. In addition, as a result of the end of the cold war and major nuclear arms reductions, the United States and Russia each have declared surplus about 50 tonnes of military plutonium, much of which may be turned into MOX fuel (even though there are significant safety, economic, and proliferation risks to this approach to plutonium disposal).12
In short, there is an enormous supply of separated plutonium, but no real demand. Nuclear utilities are unlikely to accept additional separated plutonium even if it were given away free of charge. EDF, the French utility that generates almost all its electricity by nuclear power, has been moving very slowly to implement its MOX program, and in 1995 assigned an economic value of zero to its plutonium stockpile.13 The ECN report which recommends the sale of Dutch plutonium also calculates that such plutonium has a negative market value on the order of 30 Dfl per gram of plutonium. It is unrealistic in the extreme to assume that a buyer or other willing recipient can be found for this plutonium.
At best, long-term plutonium storage only defers the question of final disposal. COGEMA and BNFL might be willing to store Dutch plutonium for an indefinite period of time, but this approach would become very costly. At an estimated storage cost of US $1 to $2 per gram of plutonium per year,14 the economic penalty for postponing final disposition of this plutonium would soon amount to millions of dollars annually. A domestic facility would require a multi-million dollar investment, and operating costs, though probably lower than the foreign charges, would still be substantial because of security and safeguards requirements.
Should the Netherlands Keep Its Plutonium in Long-Term Storage?
As these costs accumulated, inaction in the form of long-term storage would contribute to a growing proliferation threat, that is, the enormous surpluses of civilian plutonium worldwide. In the short run, plutonium surpluses increase the risk of theft or diversion by subnational groups, or by states (such as Iraq, Libya or North Korea) seeking to acquire nuclear weapons by any means. In the longer term, these surpluses add to the danger that nations possessing them will acquire nuclear weapons if circumstances change, or that regional destabilization will result because neighboring states fear the weaponization potential of plutonium stockpiles.
The best approach to the Dutch plutonium dilemma is for the government to recognize plutonium for what it is---a dangerous waste rather than a valuable asset. The Netherlands should begin to disengage itself from the plutonium economy. I offer three possible approaches for consideration.
The Netherlands Should Disengage from the Plutonium Economy
1. Cancel reprocessing contracts and take back spent fuel.
Contracts for the reprocessing of all Dutch spent nuclear fuel have been signed, but these contracts can still be canceled. In the case of older, so-called "baseload" contracts, the terms of the contract exact an economic penalty for cancellation.
The exact amounts of these penalties are not public knowledge, withheld as "proprietary" information by both the utilities and the reprocessors. The ECN report suggests that penalties for cancellation could range from 191 to 330 million Dfl, but the report concedes that these are guesses because the contracts are secret. Apparently ECN did not have access to the contracts during the preparation of its report.
Other analyses suggest that large savings would result from a shift from reprocessing to direct disposal of spent fuel.15 Four years ago, a study by Germany's federal accounting office concluded that reprocessing is more than twice as expensive as direct disposal of spent fuel, which paved the way for amendment of German law to allow a direct-disposal option. An analysis by German utilities concluded that, even accounting for large penalties for cancellation of baseload contracts, savings of US $117 per kilogram of spent fuel (over $2 billion total) would accrue if Germany shifted to direct disposal.16 Because of the absence of public information on the terms of Dutch reprocessing contracts, comparable calculations cannot be made at this time for the Netherlands.
Some later "cost-plus" contracts, such as those signed by German utilities with COGEMA in the late 1980s, contain force majeure clauses. According to authoritative trade press reports, these provisions provide "that if the German government outlaws reprocessing Cogema will return the non-reprocessed spent fuel at the customer's expense and will reimburse any advances in excess of the cost of the services rendered." The contracts also allow utilities to cancel for reasons other than force majeure, provided a sliding-scale penalty is paid.18
The Dutch Parliament should insist upon full and accurate information on the terms of Dutch utilities' reprocessing contracts, including penalty clauses, to allow the government to make an informed decision.
Unreprocessed spent fuel could be stored at the new facility SGN is designing for COVRA, pending development of a final geological repository. It should be noted that such a repository eventually will be required even if the Netherlands reprocesses all of its spent fuel, because the vitrified high-level waste (VHLW) that results from reprocessing will require final disposal.
2. Renegotiate Dutch reprocessing contracts to take back LEU fuel in place of plutonium.
Both major reprocessing firms claim (contrary to all independent economic analyses) that a MOX fuel cycle for light-water reactors already does, or soon will, cost less than a once-through LEU fuel cycle. COGEMA posits that "[t]he MOX alternative offers significant economic advantages. For example, EDF estimates that it can save 20,000 metric tons of natural uranium and 15 million SWUs, for a total fuel cycle cost savings of approximately 10%, simply by using MOX in some of its light water reactors."19 BNFL claims that "[c]urrent indications of the likely prices that will apply for MOX fuel manufacture towards the end of this decade suggest that it can be produced at prices which will give front end fuel cycle costs that are economic in comparison to natural uranium based fuel....Increased burnup will generally favor the economics of MOX fuel, all other things being equal."20
The Netherlands should use COGEMA's and BNFL's extravagant claims about the economics of MOX fuel to its own advantage. The Dutch government should renegotiate its reprocessing contracts to take back low-enriched uranium in amounts equivalent to the fissile- energy content of the plutonium separated from Dutch fuel. This LEU fuel could be stored, sold on the international market, or possibly used in the Borssele reactor prior to its scheduled shutdown in 2004.
If COGEMA, EDF, and BNFL believe that MOX fuel would accrue huge savings if substituted for LEU fuel in light-water reactors, they should be more than happy to accommodate an LEU- for-plutonium swap. If they balk at such an arrangement, at least the Dutch government will have called the reprocessing firms' bluff on the fuel-economy issue and thereby establish clearly that there is no market for this dangerous fuel. The Dutch government will also have obtained positive proof that there is no energy or "market" justification for the further reprocessing of spent fuel to obtain plutonium. All that further reprocessing could do under those circumstances is to add to the surplus of weapons-usable plutonium that is accumulating at an alarming rate.
3. Immobilize plutonium in high-level radioactive waste.
If COGEMA and BNFL make it impossible for the Dutch utilities to cancel impending reprocessing contracts or to take back LEU instead of plutonium or MOX fuel, the Netherlands should request that COGEMA and BNFL immobilize Dutch separated plutonium in highly radioactive waste. The plutonium could be mixed with ceramic or glass and placed in small cans. These cans then would be placed inside canisters at the French R7T7 and British WVP waste-vitrification facilities. There, the canisters would be filled with molten, vitrified high-level waste, locking the plutonium into the equivalent of spent fuel with a self- protecting radiation barrier. This approach, known as "can-in-canister," is currently under development in the United States for disposition of at least a part of its stockpile of surplus military plutonium.21
The advantage in this approach for the Netherlands is that it no longer will need to build and manage a high-security facility for storage of separated plutonium or fresh MOX fuel. By combining plutonium with high-level waste (actually a recombining of plutonium with the reactor wastes from which it was separated), the can-in-canister approach reduces the security burden of the plutonium to a level comparable to that of spent fuel. The VHLW canisters could then be stored in the facility now being designed for COVRA without the need for enhanced security measures.
The number of VHLW canisters to be returned to the Netherlands would increase somewhat as a result, requiring a facility with a larger capacity. The increase would depend on the details of the immobilization process.22 Assuming parameters similar to the U.S. immobilization program, the capacity of the VHLW store at COVRA would have to be increased by 10% to accommodate a total of 2.1 tonnes of separated plutonium.
To immobilize its plutonium, the Netherlands would have to pay COGEMA either to build a special process line or to modify an existing one. The required throughput would be low---200-400 kg plutonium (in 2-4 tonnes of ceramic) per year for a ten-year campaign. For a ceramic immobilization facility with a throughput of 5 tonnes of plutonium per year, the US Department of Energy estimated that the investment cost would be US $220 million. This scales to about US $40 million for a new facility with a throughput of 300 kg plutonium per year, equivalent to less than ten years' storage time for the Dutch plutonium stockpile.
Alternatively, an existing MOX fabrication line could be converted for the can-in- canister line at much lower cost. The fast breeder reactor fuel fabrication line at the CFCa plant at Cadarache, which has an annual capacity of 10 tonnes of fast reactor MOX fuel, apparently will not be needed in the future.23 This plant would be ideal for conversion to can-in-canister production. Because it handled fast reactor fuel with plutonium enrichments of up to 25%, it should be able to accommodate a 10% plutonium loading with minimal modification.
If the Dutch government paved the way for immobilization of unwanted, surplus plutonium, other governments might follow. A number of countries, especially Germany, might help to finance the project if they wish to avoid the extra costs and risks associated with MOX fuel in the future.
The viability of the can-in-canister option outlined above, as well as the viability of long-term interim storage of vitrified high-level waste in the Netherlands (whether or not the can-in-canister option is used), depends on the quality of the VHLW canisters produced by Cogema and BNFL. It is urgent, therefore, that the Netherlands inform itself of the shortcomings of the stainless steel canisters now being produced by Cogema and BNFL for the pouring, cooling and storage of the molten waste.
Action Must Be Taken to Ensure Safe Long-Term Storage of VHLW
The Nuclear Control Institute is concerned that the types of stainless steel used to encapsulate the VHLW (known as Type 309 and Type 309S austenitic stainless steels) undergo a process called "sensitization" as the VHLW canisters cool after being filled.24 Sensitization greatly reduces the steel's resistance both to certain types of corrosion and to mechanical impact. Once the canisters have been sensitized, unless extraordinary precautions are taken, the risk that the canisters will corrode and leak while in storage is greatly increased.
A number of stainless steels have been developed which are resistant to sensitization. Partly for this reason, one of these steels, Type 304L, is being used as the canister material at the HLW vitrification plants now operating in the United States and Japan. However, it should be noted that even if Type 304L is used, sensitization may occur to a limited extent during VHLW production. Other types of stainless steel may be more resistant. Why COGEMA initially chose (and continues to use) steel that is highly susceptible to rapid sensitization is not clear. We have not obtained a response to repeated attempts to query them on this matter.
A potentially serious consequence of canister sensitization for the handling and storage of VHLW is an increased susceptibility to localized corrosion processes such as "stress- corrosion cracking" (SCC) of the canister. SCC has often led to unexpected, catastrophic failures of materials. Contaminants such as chloride salts, can initiate intergranular corrosion of stainless steels at very low concentrations, if water is also present.
Because the VHLW canisters that will be returned to the Netherlands are produced, stored and shipped in marine environments (all facilities are located near oceans), the ambient air concentrations of chlorides from sea salt are always high and extreme care must be taken to prevent excessive salt contamination of the canisters. However, it is not apparent that such care is taken, especially at La Hague.
As noted, stainless steel that has become sensitized is much more vulnerable to localized, intergranular corrosion than it was when unsensitized. One consequence of using sensitized stainless steels in VHLW canisters is that uncertainties in predictions of canister performance will be greatly increased, which will reduce confidence in the results of safety analyses. This is because localized corrosion is a much more unpredictable phenomenon than uniform corrosion (e.g. it is more susceptible to small changes in environmental conditions), and less-accurate data come from applying the results of laboratory tests to predictions of long-term performance, or from extrapolating data from a single sample to an entire lot.25
At the La Hague storage facility, where the VHLW canisters are placed immediately after they are filled, the initial temperatures may be high enough to allow hot corrosion to occur on the inside of the VHLW canister. The extent of corrosion triggered by a high- temperature environment depends on the particular types of salts which are released from the glass and on their melting points (these salts are only corrosive if they are molten). Because such salts have been observed to cause intergranular corrosion, they may attack sensitized stainless steels more aggressively. Such corrosion would attack the canisters from within, where the damage cannot be directly observed.
The other storage environment relevant to corrosion is the one at low temperature (below about 100 degrees C), which occurs later in the storage period. We estimate that at a heat loading of 1.6 kilowatts per canister, the temperatures of at least some of the canisters will fall below 100 degrees C after as little as twenty years in storage. Corrosion triggered by a low-temperature environment may cause a loss of integrity of some of the VHLW canisters. Such corrosion would render ineffective one of the barriers to radioactive releases from the facility, and eventually increase the difficulty of handling the canisters when the time comes for them to be moved to the final disposal site.
At the La Hague storage facility, the VHLW canisters are directly exposed to cooling air drawn from the outside through coarse filters. Due to the coastal location of the facility, the cooling air contains moisture and chloride salts, which are not completely removed by the filters. Although the canisters are initially too hot to allow condensation of water, they are cool enough to allow some condensation of salts to occur. When the canister temperatures fall below 100 degrees C, extensive stress corrosion cracking could result.
In contrast, some VHLW storage facilities, such as those at Sellafield in the U.K. and at Rokkasho in Japan, place the VHLW canisters in an extra metal sleeve, so that direct contact of the canister surfaces with outside air is minimized.
A storage facility for VHLW is being designed and constructed at COVRA near Borssele by a French company, SGN. We are concerned that if the facility design is similar to that at France's R7T7 facility, it will not provide even minimal protection against corrosion. Even if SGN chooses a double-sleeved design such as at Sellafield, the possibility of corrosion still remains because the canisters shipped from La Hague may have been contaminated with salts prior to their receipt at COVRA.
The Nuclear Control Institute recommends, therefore, that the Netherlands both build a double-sleeved facility and require that the VHLW canisters to be shipped here be fabricated from a low-carbon stainless steel or other material more resistant to sensitization. The Netherlands should reject any attempt by France or Great Britain to send vitrified high-level waste canisters made with an inferior product.
HFR Petten Should be Converted to LEU Fuel
One important piece of unfinished business is eliminating the use of highly enriched uranium (HEU) in the HFR Petten research reactor. Petten uses about 36 kilograms of weapons-grade HEU fuel annually. Additional HEU is used in the form of "targets" that are irradiated for the production of the medical isotope molybdenum-99. Thirty-six kilograms is more than enough fissile material to build a weapon with an explosive yield that could destroy Amsterdam or The Hague.
Manhattan Project physicist Luis Alvarez warned that terrorists who obtained weapons- grade HEU "would have a good chance of setting off a high-yield explosion, simply by dropping one-half of the material on the other ... [E]ven a high-school kid could make a bomb in short order."26
The security of HEU fuel at Petten is by no means assured. It is our understanding that guards at the reactor are unarmed. In 1988, a "black hat" team of Dutch marines easily penetrated Petten's minimal security, reaching the HEU fuel storage vault in seven minutes.27
Petten could readily be converted to non-weapon-usable, high-density, low-enriched uranium (LEU) fuel. In fact, such fuel already has been developed by the U.S. Argonne National Laboratory, and was successfully tested in Petten in the late 1980s. Research and development of LEU targets to replace HEU targets for molybdenum-99 production is proceeding rapidly. NCI strongly supports conversion of the Petten reactor to LEU fuel, and would not oppose relicensing of the reactor to operate on this basis.
Unfortunately, the European Commission's Joint Research Committee (JRC), which operates Petten as a European facility on Dutch soil, refuses to convert to LEU fuel, claiming that it would be expensive and require controversial relicensing to permit operation at a higher power level. This position complicates Dutch nuclear-waste policy by eliminating the option of returning Petten's spent fuel to the United States for final disposal, an option being utilized by the vast majority of research reactor operators who have agreed to convert their facilities to LEU fuel. U.S. policy is not to take back HEU spent fuel from research reactors that could convert to LEU but refuse to do so.28
The refusal to convert Petten subverts the goal of the international Reduced Enrichment for Research and Test Reactor (RERTR) Program, which stands on the brink of fulfilling its historic mission to eliminate the use of HEU fuel in research reactors.29 Only one other large research reactor, the Safari reactor in South Africa, that was originally supplied with HEU fuel by the United States could now convert to LEU but refuses to do so.
Now that the Netherlands is paying the greatest governmental share of Petten's operating costs, the Dutch government is in a position to exercise non-proliferation leadership on the HEU issue by pressing the European Commission's JRC to come into line with the international norm by promptly converting the Petten reactor to the advanced LEU fuel that is now available. Conversion of Petten can be accomplished in stages without shutting down the reactor. It can be accomplished swiftly, and the Dutch government should take the necessary steps to see that it is.
Thank you for your attention.
End Notes1. Ann MacLachlan, "Voynet Confirms Government's Intent to Close Superphenix," Nucleonics Week, June 12, 1997, p. 2. Back to document
2. David Albright, Frans Berkhout, and William Walker, Plutonium and Highly Enriched Uranium 1996: World Inventories, Capabilities and Policies, SIPRI/Oxford UP, 1997, Table 6.4, p. 162, and Table 6.5, p. 168. Back to document
3. Ibid, Table 6.10, p. 189. Back to document
4. Paul Leventhal and Steven Dolley, "A Japanese Strategic Uranium Reserve: A Safe and Economic Alternative to Plutonium," Science and Global Security, 1994, Volume 5, pp. 1-31. A debate between NCI and British Nuclear Fuels Ltd. on this study and the economics of MOX and reprocessing was published in 1994. BNFL, Inc., "Should Japan Reprocess or Build a Strategic U Reserve?," Nuclear Engineering International, April 1994, pp. 28-29; Steven Dolley, "Japanese Strategic Uranium Reserve: A Response to BNFL," Nuclear Engineering International, September 1994, pp. 50-51. Back to document
5. Ann MacLachlan, "EPR Partners Agree to New Economic Study Phase," Nucleonics Week, October 16, 1997, p. 12. Back to document
6. "'Astounding' Discrepancy of 70 Kilograms of Plutonium Warrants Shutdown of Troubled Nuclear Fuel Plant in Japan," Nuclear Control Institute, May 9, 1994. Back to document
7. Committee on International Security and Arms Control, National Academy of Sciences, The Management and Disposition of Excess Weapons Plutonium, 1994, p. 31. Back to document
8. Bruno Pellaud, "Note to the Director General: The IAEA, the European Commission and EURATOM," December 16, 1996 (Document obtained by WISE-Paris). Back to document
9. Letter from Hans Blix, Director-General of the IAEA, to Paul Leventhal, NCI, November 1, 1990; "Blix Says IAEA does not Dispute Utility of Reactor-Grade Pu for Weapons," NuclearFuel, November 12, 1990, p. 8. However, Blix made this statement only after Nuclear Control Institute challenged assertions by IAEA safeguards officials earlier that year that reactor-grade plutonium was unsuitable for use in weapons. Recently, IAEA safeguards director Bruno Pellaud reopened the issue by proposing that safeguards on reactor-grade plutonium be weakened as a trade-off for winning nations' cooperation in the environmental monitoring and other intrusive aspects of the Agency's new "93+2" safeguards reform program. Bruno Pellaud, "Safeguards: The Evolving Picture," IAEA Bulletin, No. 4, 1996, pp. 2-6. See also Rob Edwards, "Plutonium Plan is 'Terrorist Charter,'" New Scientist, June 21, 1997, p. 5. Back to document
10. U.S. Department of Energy, Nonproliferation and Arms Control Assessment of Weapons-Usable Fissile Material Storage and Disposition Alternatives, DOE/NN-0007, January 1997, pp. 38-39. Back to document
11. Albright, Berkhout & Walker, 1997, Table 7.11, p. 235. Back to document
12. Edwin Lyman and Paul Leventhal, "Bury the Stuff," Bulletin of the Atomic Scientists, March/April 1997. Back to document
13. Ann MacLachlan, "EDF to Erase Positive Pu Value in 1995 Accounts," Nucleonics Week, November 2, 1995, p. 14. Back to document
14. Nuclear Energy Agency, OECD, The Economics of the Nuclear Fuel Cycle, Paris: OECD, 1994, p. 40. Back to document
15. Mark Hibbs, "No Justification for Reprocessing, German Accounting Office Concludes," NuclearFuel, September 13, 1993, p. 7. Back to document
16. Mark Hibbs, "End to Reprocessing of German Fuel Could Save Utilities Over $2 Billion," NuclearFuel, April 11, 1994, p. 5. Back to document
17. Mark Hibbs and Ann MacLachlan, "Germans Preparing 'Orderly Retreat' from Reprocessing, Supporting Disposal," NuclearFuel, December 21, 1992, p. 13; Mark Hibbs, "Germans Say Reprocessing Contracts Will Contain Political Force Majeure," NuclearFuel, December 11, 1989, p. 11. Back to document
18. It is reportedly the Dutch Government's position that this facility is designed only for VHLW, but SGN recently described it as "a multi-purpose facility that will concurrently store spent fuel, cemented technological waste, vitrified waste from reprocessing, and miscellaneous waste from research reactors and nuclear facilities..." SGN advertisement in Nuclear Engineering International, September 1997, p. 29 [emphasis supplied]. Also, the facility is licensed for the temporary storage of spent fuel from the HFR Petten and HOR Delft research reactors. Back to document
19. COGEMA, Inc., "The COGEMA Plant at Cadarache," March 1992, p. 1. Back to document
20. Kenneth Jackson, BNFL, "The Recycling of Plutonium and Uranium," Paper Presented at the Uranium Institute Annual Symposium, 1993, pp. 2-3. Dr. J. Paterson of BNFL claimed that "[w]hen comapred to equivalent enriched uranium fuels, LWR MOX fuel is projected to be 20-30 percent cheaper, unit-for-unit. This advantage holds for all credible conversion and separative work prices, even at the lowest commercial burn-ups, while at higher design burn-up the cost advantage increases further." Dr. J. Paterson, "Re-using Plutonium in Thermal Reactors," in "British Reprocessing," supplement to Nuclear Engineering International, October 1990, p. 8. Back to document
21. Edwin Lyman, "Just Can It," Bulletin of the Atomic Scientists, November/December 1996. Back to document
22. In the United States, plutonium loadings of up to 10 percent in titanium-based ceramics are being analyzed, and plutonium loadings of up to 4 percent are being considered for the final waste form (VHLW canisters). The total number of VHLW canisters to be returned to the Netherlands under the existing contracts is about 250, each containing about 400 kg of glass. This quantity of glass could accomodate 4 tonnes of plutonium at a 4 percent overall loading. Since the density of plutonium-loaded ceramics is about twice that of glass (5 g/cm3 versus 2.5 gm/c3), the total volume displaced by a ceramic containing 2.1 tonnes of plutonium at 10 percent plutonium loading is equivalent to about 26 canisters. Back to document
23. "Write-off Reduces Cogema's 1997 Income," NuclearFuel, October 6, 1997, p. 12. Back to document
24. Sensitization of austenitic stainless steels occurs when the steel is held for a certain period of time at a temperature in the range of approximately 400-850 degrees C. The time necessary to cause extreme sensitization depends on the composition of the steel, and in particular will decrease as the carbon content increases. Type 309 and Type 309S stainless steels have a relatively high carbon content and are susceptible to sensitization. NCI has data showing that as the VHWL canister are being cooled after being filled with glass, the canister temperature remains within the sensitization range for several hours, long enough to cause extensive sensitization. Back to document
25. One such uncertainty is the extent to which the stainless steel containers will be subjected to potentially corrosive environments during storage and transport of VHLW. Soon after filling, the canister may be susceptible to 'hot corrosion" (otherwise known as "catastrophic oxidation") from exposure to molten salts released from the VHLW, such as cesium oxide. After several years of cooling, the canister surfaces will have cooled sufficiently to allow moisture to condense on them, which can enable stress-corrosion cracking to take place. Back to document
26. Luis Alvarez, Adventures of a Physicist, New York: Basic Books, 1987, p. 125. Back to document
27. Ben Wouters, "Reactor Petten aanlokkelijk doelwit voor terreuracties," Schager Courant, February 7, 1991. Back to document
28. U.S. Department of Energy, "Record of Decision for the Final Environmental Impact Statement on a Proposed Nuclear Weapons Nonproliferation Policy Concerning Foreign Research Reactor Spent Fuel," Federal Register, May 17, 1996, p. 25096. Back to document
29. The RERTR Program has proved remarkably successful. Of the 42 research reactors with power of at least 1 megawatt that were originally supplied HEU fuel by the United States, 37 have either converted to LEU, are in the process of converting, or have no further need for fuel, enabling a sharp decline in U.S. HEU exports. See Alan Kuperman and Paul Leventhal, "RERTR End-Game: A Win-Win Framework," Paper Presented at the International Meeting on the RERTR Program, Jackson Hole, Wyoming, October 5-10, 1997. Back to document
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