In late June the United States and Kazakhstan completed a joint project to package spent fuel containing weapons-grade plutonium for permanent storage. Conclusion of the work represents a key milestone in a multi-year effort to inventory, secure, and permanently store material containing some three tons of plutonium in order to make it less susceptible to theft.
Presidents Bill Clinton and Nursultan Nazarbayev agreed in November 1997 to a three-part program to accurately inventory spent fuel produced by a Soviet-era BN-350 breeder reactor located in Aktau, Kazakhstan; seal the material in casks; and place it in permanent storage under International Atomic Energy Agency safeguards. Under a parallel agreement signed in December 1999, the United States is also helping to shut down the breeder reactor permanently.
The packaged fissile material is currently stored in cooling ponds at the breeder-reactor complex on the shores of the Caspian Sea. Technicians have been working on-site since December 1998 to place the reactor’s used fuel assemblies into an estimated 2,800 one-ton, 13-foot long, welded steel canisters. Radioactive waste was placed in the canisters before they were sealed, resulting in a “heavy, hot, and highly radioactive package that is far more difficult to steal,” according to the Energy Department’s Defense Nuclear Nonproliferation office.
The project’s next step involves construction of a longer-term storage facility for the material, since the fuel canisters in which the plutonium is currently stored are only designed to maintain their integrity for five years while submerged in the cooling ponds. Scientists from the U.S. Argonne National Laboratory have proposed constructing a dry-silo facility that would be engineered to contain the material for 50 years. (A U.S. official indicated that after 50 years Kazakhstan, which is currently pressed for funds, is expected to be able to finance the construction of a more permanent disposition facility.)
After evaluating 10 possible locations for the dry-silo facility, a team of Argonne scientists recommended two long-term sites, one at the former Soviet nuclear test site of Semipalatinsk in northeastern Kazakhstan, near the Russian border, and the other in Aktau, near the reactor complex. Aktau’s coastal location in the vicinity of several nuclear weapons aspirants, notably Iran, served as a prime motivator for the joint threat reduction effort. As a result, early discussions on the issue of permanent storage focused on moving the material far inland, and the Kazakh government has announced that it would like the material to go to Semipalatinsk, the more costly of the two possibilities. But U.S. government officials emphasized that both storage site options remain on the table.
No agreement has yet been reached on the issue, and according to a U.S. official, the whole issue of short- and longer-term storage options “is now being re-evaluated.” However, because the plutonium can only be kept dry in the cooling ponds for five years, terminating the cooperative U.S.-Kazakh effort at this stage would make any long-term storage effort considerably more difficult, the official said.
Even among Clinton administration officials, who initiated the project, there was some disagreement regarding the necessity of constructing a costly longer-term disposition site at Semipalatinsk. Although the fissile material’s quantity, quality, and location put it at risk of diversion or even forcible seizure, the fact that it remains in spent fuel elements and is now protected by additional highly radioactive waste significantly reduces those risks. With the administration seeking substantial nuclear threat reduction budget cuts, Energy Department officials may ultimately decide that other projects—some involving unprotected, separated fissile materials—pose a greater short-term proliferation threat. (See ACT, April 2001 and May 2001.)