Behavior of Spent Fuel and Safety-Related Components in Dry Cask Storage Systems

摘要

A Castor-V/21 cask containing 21 spent PWR rods (burnups in the 30-35 GWd/MTU range) has been in storage at thernIdaho National Environmental and Engineering Laboratory (INEEL) since 1985. This cask represents one of the longest storagernperiods in the current fleet of licensed dry storage containers in the United States. Given that current dry storage cask licensesrnare only for 20 years, and several cask systems are approaching the end of the initial license period, it is necessary to establishrna technical basis for extended storage. Consequently, the Nuclear Regulatory Commission, the Electric Power Research Institute,rnand the Department of Energy have embarked upon a cooperative research program to assess the integrity of this cask in orderrnto establish a partial basis for extended dry storage in existing licensed casks. The Castor cask has been reopened and the caskrninternals, fuel assemblies, and selected rods from one fuel assembly have been visually inspected at the INEEL. The cask, andrnthe stored fuel rods appeared to be unchanged by the long storage duration.