Burnup Credit in the Criticality Safety Analyses of Pressurized Water Reactor Spent Fuel in Transportation and Storage Casks

摘要

The U.S. Nuclear Regulatory Commission (NRC or the Commission) is issuing a Spent Fuel Storage and Transportation Interim Staff Guidance (SFST-ISG)-8, Revision 3, entitled, "Burnup Credit in the Criticality Safety Analyses of PWR [Pressurized Water Reactor] Spent Fuel in Transportation and Storage Casks." This SFST-ISG provides guidance for use by NRC staff when reviewing applications requesting burnup credit in the criticality safety analyses of pressurized water reactor spent nuclear fuel (SNF) in transportation packages and storage casks. SFST-ISG-8, Revision 3, includes two major changes in the staff recommendations: (1) optional credit for fission product and minor actinide neutron absorbing isotopes in the SNF composition, and (2) misload analyses and additional administrative procedures in lieu of a burnup measurement at the time of loading.