Burnup Credit Issues In Spent Fuel Transport

Burnup credit has been successfully applied to spent fuel storage pools in the United States, resulting in increased capacity and permitting the storage of spent fuel with higher initial enrichments. The regulatory acceptance of transport cask design incorporating burnup credit and its benefits depends on the identification and resolution of issues that affect the determination of criticality safety margins. The factors contributing to the determination of criticality safety have been examined by fault-tree analysis to compare the issues involved in both the "fresh fuel" and "burnup credit" approaches to criticality safety.