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Paul Leventhal, Milton Hoenig and Alan Kuperman

I. Overview of the Problem

President Reagan may soon approve and submit to Congress a new nuclear cooperation agreement that his Administration has negotiated with Japan. The agreement would give Japan advance approval to reprocess, over the next 30 years, U.S.-supplied and -controlled nuclear fuel after it is removed from Japanese power reactors. The reprocessing of the spent fuel would result in chemical separation of plutonium for use as a fuel in Japan's nuclear power program.

If the new agreement is approved by the President and is not rejected by Congress, the Japanese will have a blanket authorization to separate all the U.S.-controlled plutonium produced in Japanese reactors. This plutonium will make up most of the 85 metric tons 187,000 pounds] of plutonium that will be produced in Japanese spent fuel by the year 2000.

Plutonium is a man-made element that is created as a waste byproduct of reactor operation. It is highly toxic, and it can be used in nuclear weapons. Laboratory experiments show that microgram quantities can cause cancer. Five to eight kilograms [11 to 18 pounds] is sufficient for use in a "primitive" fission bomb of the type that destroyed Nagasaki. (The United States now has about 100 metric tons [220,000 lbs.] of plutonium in its stockpile of nuclear weapons.)

More than half of the 85 metric tons would be separated by reprocessors in Europe, and then transported back to Japan. The first such shipment was made by ship from France to Japan in 1984. The five-week voyage involved such large risks and required such massive military escort and surveillance activities, that both the United States and Japan agreed that future shipments should be made by air.

Present plans call for air shipments of plutonium to cross over Canada, land for refueling in Alaska, and then proceed to Japan. There are a number of problems with the execution of these plans:

1. Commercial air shipment of multi-ton quantities of plutonium is unprecedented. A few flights of no more than 100 pounds each had come into the United States before enactment of the Scheuer Amendment (P.L. 94-79) in 1975. This law barred the Nuclear Regulatory Commission from licensing "any shipments by air transport of plutonium in any form, whether exports, imports or domestic shipments" until the NRC certified a cask capable of surviving "the crash and explosion of a high-flying aircraft."

2. A cask large enough for efficient, large-scale shipment of the Japanese plutonium has not been certified by the NRC. A prototype cask, weighing 5,000 pounds and designed to hold about 15 pounds of plutonium, failed a high-velocity impact test at Sandia National Laboratories last summer.

3. If the cask now being developed is eventually used, one Boeing- 747 shipment of more than 500 pounds of plutonium would be required every two weeks---taking off from France or the United Kingdom, overflying Canada, landing for refueling in Alaska, and then taking off again and finally landing in Japan. These flights may prove to be of considerable local and national concern. Canada has had one experience with radioactive fuel falling from the sky, during the reentry of an orbiting Soviet satellite in January, 1978.

4. If the cask proves to be technically unfeasible-as some experts advise us will be the outcome-plutonium air transport (PAT) may have to be accomplished with existing, smaller PAT-1 casks, which were never intended for such large-scale transport.

5. The Japanese shipments may not be subject to licensing by the NRC because, although the Commission is responsible for licensing initial exports of uranium fuel, all subsequent arrangements involving spent fuel and the plutonium contained in it are approved by the Department of Energy. The safety of DOE-approved shipments of separated plutonium comes under the jurisdiction of the U.S. Department of Transportation when any such shipments are flown into U.S. airports and/or air space. According to a DoT official, the Transportation Department probably would consult with the NRC on approving a cask, but the DoT would make clear to the NRC that only the International Atomic Energy Agency (IAEA) standards for safe transport need be met.

The IAEA standards are far less demanding than those set by the NRC. For example, the IAEA impact test requires a velocity of only 44 ft./sec., while the NRC-mandated test requires a velocity of at least 422 ft./sec. Further, the IAEA crash standards are no more stringent for plutonium casks than they are for casks used for less hazardous nuclear materials.

The Scheuer Amendment prescribes extra precautions for NRC- licensed plutonium transportation, owing to plutonium's extreme toxicity. The Administration, however, appears to be interpreting the Atomic Energy Act in a way that could permit foreign plutonium to be flown into an Anchorage airport in casks that need not meet the NRC's strict standards.

The Atomic Energy Act requires NRC licensing of domestic, commercial plutonium shipments, as well as imports of plutonium for commercial use in the United States. (There are presently no such shipments because of Congressional actions resulting in the shutdown of all elements of the U.S. commercial plutonium program-spent-fuel reprocessing, fresh-fuel fabrication and breeder-reactor development.) However, plutonium-bearing cargo planes landing for refueling in the United States, on their way from Europe to Japan, apparently are viewed by the Administration as neither domestic nor import shipments. This interpretation could create a loophole not intended by Congress: flights of foreign plutonium stopping in the United States may be approved by the DoE on the basis of cask-safety criteria substantially inferior to those set by the NRC.

In the face of known dangers and high clean-up costs associated with environmental releases of plutonium, the United States-under the agreement negotiated by the Reagan Administration with Japan- would acquiesce in the development of a Japanese plutonium fuel economy that could result in a planeload of plutonium landing in Anchorage as often as every two weeks.

Crashes of two U.S. military aircraft carrying nuclear warheads, which resulted in the release of substantial amounts of plutonium, serve to illustrate the problem. One crash occurred at Palomares, Spain, in January, 1966 after a bomber and a tanker collided in a routine mid-air refueling operation. Clean-up of 1,400 tons of contaminated soil and vegetation at Palomares cost S500-million. The crash of a bomber carrying four nuclear weapons at Thule, Greenland, in January, 1968, required the removal of one and a half million gallons of contaminated snow, ice and water at a cost of $300-million. Both of these sites were unpopulated. Plutonium contamination of a more densely populated crash site would involve a public health risk, and evacuation and decontamination costs would be many times higher.

Under the present U.S.-Japan nuclear agreement, which expires in 2003, the Japanese must obtain U.S. approval of each of their reprocessing, plutonium-transfer and plutonium-use requests. Thus, the existing agreement permits the United States to withhold approval of air shipments of U.S.-controlled plutonium in the absence of a crash-proof cask that meets NRC's specifications. The new agreement would replace the existing case-by-case review process with a blanket U.S. approval of Japanese plutonium activities for the 30-year life of the agreement.

By the early l990s, Japan will have 5,250 kg. [11,550 lbs.] of plutonium separated each year from spent fuel by reprocessors in the UK and France-the equivalent of 5,950 kg. [13,090 lbs.] of plutonium oxide-according to David Albright in "Civilian Inventories of Plutonium and Highly Enriched Uranium."1 Out of a total of 48 metric tons of plutonium to be separated in Europe for Japan by the year 2000, 45 metric tons are from fuel irradiated in light water reactors (LWRs). According to Albright, a physicist with the Federation of American Scientists, at least 80 percent, if not virtually all, of this LWR-produced plutonium is to be separated from fuel supplied by the United States or used in U.S.-supplied reactors and, therefore, comes under U.S. control.

Air shipments of commercial plutonium of the magnitude to be authorized by the Japanese agreement have never occurred. Indeed, these shipments may exceed the amounts of plutonium now shipped by air for the U.S. nuclear weapons-program.

The significance of the plans to ship plutonium by air is underscored by the on-going development of a communications system for the International Atomic Energy Agency to continuously monitor the integrity of casks during flight, to verify that none of the plutonium has been stolen or diverted. The system, called Artemis, is being designed and set up by the U.S. Arms Control and Disarmament Agency. It will use the private Inmorsat satellite to monitor tamper-indicating seals in "real-time" and the U.S. Navstar Global Positioning System to accurately track the position of the aircraft.

II. Brief Historical Background

In January 1978, the NRC, pursuant to the Scheuer Amendment, published NUREG-0360, "Qualification Criteria to Certify a Package for Air Transport of Plutonium," which detailed: (1) a rigorous set of crash, burn and submersion simulations, to which any potential cask would have to be subjected before its certification; and (2) operational conditions for air transport of plutonium, which would have to be followed to ensure the integrity of the cask and its contents.

By June 1978, the safety analysis report on the first prototype cask, the PAT-1, was published, and by August 1978, the NRC officially certified the cask for use. The PAT-1 weighed approximately 500 lbs. and was cylindrically shaped, with a length of 42.5 inches and a diameter of 24.5 inches. It was authorized to hold up to 2 kg. [4.4 pounds] of plutonium oxide, uranium oxide, their daughter products, or any mixture thereof.

The only real need for air transport of plutonium at the time, however, was for quick, international delivery of IAEA plutonium samples---for analysis as part of their international safeguards procedure. The amounts with which the IAEA was dealing were very small, but were still large enough to require a cask under the law's provisions. The size of the PAT-1 was overkill for these small samples, and as a result, its use would have strained the budget of the IAEA.

The IAEA thus asked the U.S. government to help develop a Light Weight Air Transportable Accident Resistant Container (LATARC), later known as the PAT-2. By September 1981, the PAT-2 had been developed, tested and licensed for use by the NRC, weighing only 73 pounds but holding only 40 grams of plutonium oxide, which was satisfactory for the IAEA's needs, but clearly inadequate for large scale transport. Because the operating procedures specified by NUREG-0360 still made the casks' use prohibitively expensive, the NRC reviewed these operational guidelines and eventually relaxed them by easing restrictions on tying-down the casks, removing the requirement that the casks be stowed on the plane's main deck, and shortening the list of other hazardous cargo that could not be aboard flights containing the casks. The NRC concluded that these new, less stringent guidelines did not "significantly" affect the ability of the PAT-2 package to withstand the crash and explosion of a high flying aircraft.

Since then, 'the only major advance in the development of these casks was the development of a modified PAT-1, which could carry 3.15 kg. of plutonium metal, as opposed to the original 2 kg. of plutonium oxide. This modified PAT-1 was licensed for use by the Department of Energy, but was never submitted to the NRC, because there were no NRC-licensed transports of plutonium taking place at the time. There are no indications that the Japanese are considering shipping the plutonium in its highly flammable (pyrophoric) metallic form, which is also the preferred form for use in weapons.

III. The Present Situation

The PAT-1 and PAT-2 are thus the only two NRC-certified casks in existence for air transport of plutonium. A number of firms around the world, including PNC (Japan), COGEMA (France), and BNFL (UK), are working on developing a larger cask that would make commercial shipment of reprocessed plutonium economically efficient.

The only acknowledged test of such a cask took place at Sandia National Laboratories in the summer of 1986. It was an impact test of a prototype PAT-3 cask developed jointly by PNC and Battelle-Columbus. The cask weighed about 5000 lbs. and was designed to hold 6-7 kg. [about 13-15 lbs.] of plutonium oxide. The cask was propelled into a hard target at more than 422 ft/sec. (250 knots---the maximum legal air speed below 10,000 ft. and the speed specified by NUREG-0360). The cask failed the test, and no new prototype has yet been tested or scheduled for testing at Sandia, according to knowledgeable Sandia officials. One such official said Battelle has "gone back to the drawing board."

When we asked a leading expert on the engineering of casks to predict when a large, crash-proof cask with a capacity of 6-10 kg. of plutonium oxide would be developed, he replied: "Never." He explained that due to the rigor of the NUREG-required tests, there was a limit to the size of any cask, because past a certain size, the cask "committed suicide"---that is, it collapsed on itself. Thus, he felt that there was an absolute limit---barring an unforeseen developmental breakthrough---to the size of a crash-proof PAT-3 cask, and a corresponding limit to the amount of plutonium that it could hold.

The limitation on size results from a basic principle of engineering which states that as the size of a structure is increased, the weight of the structure grows much faster than the strength. Thus, as bigger casks are developed, the force of impact eventually overwhelms the strength of the package.

IV. Air Transportation Facts for Proposed New PAT-3

According to various informed sources, the PAT-3 cask, if successfully developed, would weigh 5,000 pounds, hold 6 to 7 kilograms of plutonium oxide, and be packed three casks at a time into shipping containers for transport in Boeing-747 cargo planes. The 747s have a maximum cargo load of 255,000 lbs. according to NUREG-0360.

Thus, we can calculate the maximum capacity of plutonium flights using the PAT-3 casks:

Each shipping container would hold 3 casks. A typical container would have a capacity of 12.5 short tons and itself weigh 2,600 lbs. The weight of a packed container would be at least 15,000 pounds for the casks [3 x 5,000 lbs.] plus 2,600 lbs. for the container, or a total of 17,600 pounds. With the addition of packing materials, the total weight of a filled container would likely be as large as 20,000 pounds, or 10 short tons.

Based on its total weight capacity, a 747 could carry some 12 or 13 containers, depending on the added packing materials. Given that each cask can hold 6-7 kg. of plutonium oxide, each container would hold 18-21 kg. [40-46 lbs.] of plutonium oxide, and there would be from 216 kg. to 273 kg. [475 to 600 lbs.] of plutonium oxide in a single 747. Thus, the likely load on each 747 shipment to Japan would be about 250 kg. [550 lbs.] of plutonium oxide. Because of the heavy load, a 747 would need to refuel in Alaska en route from Europe to Japan.

Volume capacity would not be a problem. According to our calculations, a 747 cargo flight could hold 14 of the above-discussed containers plus additional containers of smaller size if weight were not a factor.

As discussed above, the Japanese will have 5,250 kg. of plutonium per year separated by reprocessors in Europe by the early l990s, or the equivalent of 5,950 kg. of plutonium oxide. At 250 kg. [550 lbs.] per 747 flight, that would mean at least 23 flights per year.

Thus, in order to move the estimated 45 metric tons of plutonium that European reprocessors will separate from LWR spent fuel for Japan by the year 2000, a 747 carrying over 500 pounds of plutonium would have to fly over Canada and land in Alaska every two weeks by the early l990s.

It is by no means clear, however, that a PAT-3 crash-proof cask can be developed. Such flights may use a cask that does not meet the NRC's present strict requirements, if DoE and DoT choose not to require it. It also should be noted that the last time the NRC's operational requirements hindered use of a cask (the PAT-2), those safety restrictions were relaxed by the NRC itself.

V. Calculations for Air Transport Using PAT-1

If use of a PAT-3 cask eventually is barred because one cannot be developed to meet the NUREG 0360 crash standard, the only NRC-certified cask that exists for potential large-scale shipment of plutonium is the PAT-1.

We estimate that as many as 350 PAT-1 casks, each weighing 500 lbs., could be carried on one dedicated 747 flight. At 2 kg. of plutonium oxide per cask, this yields a capacity of 700 kg. 1540 lbs.] of plutonium oxide per flight. Thus, transporting 5,950 kg. [about 13,000 lbs.] of plutonium oxide per year could be done with as few as nine 747 flights per year, each carrying about 1,500 pounds of plutonium oxide.

There are serious technical obstacles, however, to the use of this cask for such commercial transport. According to an NRC official, substantial safety issues would have to be resolved in connection with shipments of such large quantities of plutonium. For example, a 747 fully loaded with PAT-1 casks would be more vulnerable to severe consequences from an engine-rotor accident or a mid-air collision (see next section).

In addition, there is a practical obstacle to use of the PAT-1: neither of the two versions of PAT-1 now in existence is capable of holding a COGEMA plutonium container, which is used to store Japanese plutonium in France. Nevertheless, according to an NRC official, there were indications in 1986 of possible Japanese interest in using the PAT-1 for large-scale plutonium transport. However, when COGEMA was asked to modify its plutonium container for use in the PAT-1, the French plutonium producer refused, according to a knowledgeable source. Further, this official said, the three firms actively working on casks---PNC (with Battelle-Columbus), BNFL, and COGEMA---all have resisted suggestions simply to modify the PAT-1 design in order to fit the COGEMA plutonium container, even though, according to him, that modification could be performed by the right engineer. The clear preference has been to develop a crash-proof PAT-3 cask.

VI. Other Cask Issues

1. If a PAT-3 cask is developed that survives the simulated crash test required by NUREG 0360, or if the PAT-1 cask is selected for use in its place, it would be desirable to ascertain, and to demonstrate to the public, that a full complement of casks will survive an actual plane crash. This objective can be accomplished by crashing a 747 with a full load of casks containing non-radioactive material. As learned from a December 1984 FAA crash test of a Boeing-720, actual crashes can have very different consequences than simulated crashes in a laboratory. In that test---which cost $11.8-million--- flame-proof fuel that had been tested successfully in laboratory crash tests, burst into a fireball when the Boeing 720, using the fuel, was actually crashed.

According to knowledgeable officials, the NRC originally considered crashing the PAT-1 cask in a retired naval plane, which was set aside at Sandia specifically for such a test, but they decided not to because of the expense---less than 510-million---of monitoring equipment. An actual crash test of the PAT-3 casks and containers in a Boeing-747 may cost (including the price of an older 747) as much as S25-million---an expense that should be considered in the context of increased assurance of the casks' integrity and in relation to the enormous cost of cleaning up a plutonium spill.

2. There is the possibility of a terrorist attack on a plane carrying these casks, especially during take-off and landing, during refueling, and during loading and unloading of the cargo. When the cask specifications were developed, the terrorist contingency was not specifically considered, according to knowledgeable officials.

3. The NUREG-0360 cask specifications do not take into account the possible consequences of a mid-air collision in which a cask is directly hit. The regulation states (page 47) that "in the event of fuselage-to-fuselage collision,...if the package is in a position to be struck directly, the severity of the resulting impact is difficult to predict." Such a collision could occur near a busy airport or during mid-air refueling, as occurred at Palomares, Spain. At present, Japanese plans are to land for refueling in Alaska, not to refuel in mid-air.

4. At the time NUREG-0360 was written, there was concern that an engine-rotor accident could damage a cask. Since the NRC was considering the transport of no more than a few casks at a time, it required that the casks be placed in the aft-most section of the main deck in order to preclude placement near the engine rotors. A plane that is fully loaded with casks would, however, have casks near the engine rotors. According to an NRC official, a complete reevaluation would be required before a cask for use in a plane fully loaded with casks would be licensed, and the issue of an engine-rotor accident would have to be reconsidered.

5. Three firms are known to be working on PAT-3 casks: PNC (through Battelle-Columbus), BNFL, and COGEMA. At the PATRAM-86 (Packaging and Transportation of Radioactive Materials) conference in Davos, Switzerland, each gave a presentation on the progress of their work and predicted success by the end of 1986. A pre-publication copy of the presentation by PNC indicates that the testing and approval of the PAT-3 was supposed to be completed by the end of 1986. As noted above, however, the PAT-3 failed its only test at Sandia National Laboratories, and new tests of an improved prototype have yet to be scheduled.

To date, there have been no reports of any tests in the technical journals. Further, attempts to acquire test results through the individual firms and their respective embassies have not yet proved successful. It is understood within the technical community, however, that the French tested their prototype PAT-3 about one year ago and that the impact test was a complete failure, resulting in a shattered cask.

6. The Japanese are developing their own plutonium air transport regulations, which are likely to be very similar to the NUREG specifications. It is not clear, however, what the final Japanese specifications will be in the event a crash-proof PAT-3 cannot be developed. It is expected that the Japanese will require at least two more years to develop their regulations and that the first air shipments of plutonium will begin after 1990.

IX. Conclusion

There are many technical issues to be resolved before it can be determined whether commercial air transport of plutonium, as envisioned in the upcoming U.S.-Japan nuclear agreement, can be achieved safely and securely. Considerable uncertainty still surrounds the development of a crash-proof cask suitable for use in large shipments of plutonium. Further, there are environmental and security implications important to the United States in the establishment of a plutonium fuel economy in Japan. It is premature, therefore, for the Reagan Administration to negotiate away U.S. authority over how Japan makes use of plutonium contained in spent nuclear fuel originally supplied by the United States or used in U.S.-supplied reactors. The President should not submit the new U.S.-Japan agreement to Congress until all technical issues with regard to air transport of plutonium are resolved.

In addition to air-transport safety questions, there are questions concerning the vulnerability of commercial, weapon-usable plutonium to attacks or thefts by terrorists, as well as the eventual spread of this material to nations seeking the capability to build nuclear weapons. From both counter-terrorism and non-proliferation perspectives, the risks of commercial use of plutonium may outweigh any energy benefits of using this fuel. Further, use of plutonium fuel is no longer regarded as economical because of abundant, low-cost supplies of uranium now available on the world market. The uranium used to fuel nuclear power plants, in contrast to plutonium, is not suitable for use in nuclear weapons. These are yet further reasons why the President should not sign away U.S. veto power over the development of a Japanese plutonium fuel economy.

End Note

1. This paper appears in Nuclear Terrorism: The Report and Papers of the International Task Force on Prevention of Nuclear Terrorism, A Nuclear Control Institute Book, Lexington Books, 1987, pp. 265-291.Back to document

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