(April 21, 1992) The shipping casks that are to be used for ocean voyages of highly toxic plutonium from Europe to Japan later this year are built to standards that fall below fire, collision and immerison conditions that have occurred in serious accidents and attacks at sea, according to a report by maritime safety experts.
(370.3633) WISE-Tokyo - The report, which was released on 8 April in Tokyo, London and Washington by the Nuclear Control Institute (NCI) and Greenpeace International, gives examples of several recent maritime accidents which created conditions far more severe than considered for International Atomic Energy Agency (IAEA) cask tests.
The report was prepared by ECO Engineering of Annapolis, Maryland, US. The firm is operated by former US government maritime transport experts and specializes in assements and risk analyses of hazardous cargoes, including radioactive wastes, for government and commercial clients in the US and other countries. It was requested by NCI and Greenpeace after the two organizations learned that the US government is not reviewing the safety specifications of the casks to be used by Japan to ship the extremely toxic plutonium from France and England. The shipments, due to start this summer or fall, will contain about one metric ton of plutonium each.
An accident could affect people in Europe or Japan and, depending on the route to Japan, in South America, Africa, and the Pacific region, as well. Under the terms of the arrangement with the US, Japan must prepare a contingency plan that includes arrangements made in advance with nations en route for emergency port calls in the event of trouble at sea. Possible routes include around South America or Africa, or through the Panama Canal. [The first shipment of plutonium extracted from Japanese spent fuel at la Hague, in France, is scheduled for later this year. Shipments from Sellafield, UK, could begin soon after. Depending on the route taken, the 15-17,000 mile journey could take the British flagged 'Pacific Crane', which will transport the cargo, through the Panama Canal or around Cape Horn or the Cape of Good Hope.]
The US government has responsibility as the supplier of nuclear fuel from which the plutonium is separated. Because separated plutonium is used to make nuclear weapons, the US is reviewing a top secret security plan now being developed by Japan and France for the first shipment to protect against hijackings by terrorists or rogue states. Each shipment will contain enough plutonium for at least 125 bombs.
However, a US government official told representatives of NCI and Greenpeace that the US is not examining the safety of the shipments beyond accepting Japan's assertion that the shipping casks meet safety standards established by the IAEA. Yet, according to ECO Engineering's report, "The duration and intensity of shipboard fires, the enormity of the energy levels associated with ship collisions, and the extent of hydrostatic pressure of the ocean depths, to say nothing of the consequences of acts of terrorism, would appear to create exposure environments beyond the limits of the casks designed in accordance with IAEA standards."
The fuel involved in the planned shipments was used in Japanese reactors to produce electricity and then shipped by sea to France and British reprocessing plants. Reprocessing separates the used fuel into uranium, plutonium, and highly radioactive wastes. The separated plutonium is to be shipped back to Japan for reuse in power reactors under a revised US-Japan agreement for nuclear cooperation, signed in 1987. The European reprocessors will return the nuclear wastes later to Japan.
The plan to ship the plutonium has run into many problems because of the difficulty in protecting this toxic and explosive nuclear material. The original plan to ship it by air was abandoned in 1987 after Japan failed to develop a crash-proof shipping cask. The ECO Engineering report was commissioned by NCI and Greenpeace to assess whether there is adequate information to support a Japanese claim that the sea shipment casks are safe.
According to the report, "Based upon the documentation furnished, there is no substantive evidence to support any claim relative to the integrity of a cask exposed to the consequences of a maximum credible marine accident." The report noted a lack of information on how the nuclear transport ship and one armed Japanese escort vessel would be operated in congested waters near populated areas or in making emergency port calls after an accident or attack at sea. "Thus," according to the report, "there is a risk of the release of plutonium in heavily trafficked waterways and ports where ship collisions are most likely to occur and where population centers tend to be located ? both of which would increase the involuntary risk to the public."
Regarding a claim by the UK Atomic Energy Authority that the loss of a plutonium ship would occur on the order of once in a half-million years and that a severe fire would occur once in a million years, the report said: "There is no data to support the claimed incredibility of the occurrence of such events. In fact, historical occurrence of the type of accident events necessary to place the casks in jeopardy do occur...and nothing in the furnished documentation gives any definitive basis as to why the historical frequency will be mitigated by the intended manner of transport."
Specifically, the report noted, while the IAEA standard is for a cask to survive a fire of 1,472 °F (800 °C) for a half hour, "shipboard fires routinely exceed 2,000 °F, or nearly 1,100 °C, have an average duration of nearly one day, but often extend over a period of days and sometimes weeks."
In addition, although the IAEA standard requires that a cask survive immersion to a depth of 200 meters for one hour, one US government study reported that plutonium sea shipment casks will begin to fail at 200 meters and collapse totally at 3,600 meters. The report noted that depths beyond 200 meters will be encountered along 75 to 90 percent of the plutonium ship's route.
"It also appears credible that the nuclear transport vessel could sink in sufficiently deep water to externally pressurize the cask to the point of collapse with subsequent release of the plutonium into the ocean," the study found.
The report also suggested that the casks could not withstand the enormous forces of a credible collision at sea. It pointed out that the relatively small size of the plutonium transport vessel causes "additional concern for its survivability following an accident." It noted that the vessel will be exposed to "some of the mor unforgiving areas (in terms of weather, wind and wave environments) of the oceans without any port calls between Europe and Japan" and that the large amount of fuel oil needed for the nonstop voyage also raises added concern about the possibility of fires, "should that fuel be ignited for any reason, including a ship collision or terrorist strike."
Regarding the threat of terrorism, the report quoted from a US Pentagon study that warned that "...even if the most careful precautions are observed, no one could guarantee the safety of the cargo from a security incident, such as an attack on the vessel by small, fast craft, especially if armed with modern anti-ship missiles." The report cited the intense heat caused by the single EXOCET missile that hit and destroyed the HMA Sheffield during the Falklands war.
Following the release of the report, NCI and Greenpeace, in addition to several other environmental and arms control groups, have requested that the US House Foreign Affairs Committee and the Senate Foreign Relations Committee hold hearings on the safety hazards and proliferation risks posed by the plutonium shipments. The US State Department recently held initial briefings for House and Senate staff members.
Sources: NCI and Greenpeace press release, 8 Apr. 1992.
Contact: Steven Dolkey, Nuclear Control Institute, 1000 Connecticut Ave. NW, Suite 406, Washington DC 20036, USA; tel: +1-202-822 844.
Rebecca Johnson/Shaun Burnie, Greenpeace International, Keizersgracht 176, 1016 DW Amsterdam, Netherlands, tel: +31-20-523-6557.
Thomas Clements (Greenpeace USA), tel: +1-202-462-1177.
Damon Moglen (Greenpeace London), +44-71-354-9100. San Al (Yokohama, Japan), tel: +81-45-242-4411; fax: 242-7485.