Transportation Requirements for the Disposition of Excess Weapon Plutonium by Burning in Fission Reactors·

Both the United States and Russia, as pan of a mutual program to ensure peaceful intentions (to one another and the international community), are planning to dispose of about 50 Mg of excess weapon plutonium over a 25-year period. One option is to transfer the plutonium to Advanced Light Water (power) Reactors (AL WRs) for use as fuel. Subsequent disposal would then be considered \"commercial\" spent fuel. This disposition option, like others, involves the transportation of plutonium in various material forms as it proceeds through various points in the recovery operation. This paper examines both the disposition option and the issues surrounding the transportation of 50 Mg of excess plutonium within the United States under current regulatory and infrastructure constraints. Transportation of plutonium and associated wastes will be subject to government regulations and Department of Energy (DOE) orders. At its discretion, DOE may adopt national-security exemptions for transporting sensitive forms of special nuclear materials. Such instances have become increasingly rare. Different regulations may apply for different ponions of the plutonium- recovery operation, which generally stans with weapon pits and ends with feed material for fuelelement fabrication. Following the fuel-element fabrication, the fresh fuel assemblies will be shipped to the reactor site where they will be fissioncd in AL WRs. The spent fuel will be stored on site for some specified time prior to shipment to a disposal facility. Transportation issues include criticality control, shielding, and containment of the contents. Allowable limits on each of these issues are specified by the applicable (or selected) regulation. The composition and form of the radioactive materials to be transported will determine, in pan, the applicable ponions of the regulations as well as the packaging design. The regulations and the packaging design. along with safeguard and security issues, will determine the quantity of plutonium or fuel assemblies per package as well as the number of packages per shipment and the type of highway carrier. For the disposition of 50 Mg of weapon plutonium using AL WRs in a 25-year campaign, the annual shipment rates are determined for the various types of carriers.