CSER-00-007 Addendum 1 Criticality Safety Evaluation of Shippingport PWR Core 2 Blanket Fuel Assemblies at Lower Exposures

This analysis meets the requirements of HNF-7098, Criticality Safety Program, (FH 2001a). HNF-7098 states that before starting a new operation with fissile material or before an existing operation is changed, it shall be determined that the entire process will be subcritical under both normal and credible abnormal conditions. To demonstrate the Incredibility Principle is satisfied, this Criticality Safety Evaluation Report (CSER) shows that the form or distribution is such that criticality is impossible. This evaluation demonstrated, that on the basis of effective 235U enrichment, criticality is not possible. The minimum blanket assembly exposure is 4,375 MWtd/MTU for fissile material that is shown to fulfill the Incredibility Principle safety criterion on the basis of enrichment