Recent Use of Covariance Data for Criticality Safety Assessment

The TSUNAMI codes of the Oak Ridge National Laboratory SCALE code system were applied to a burnup credit application to demonstrate the use of sensitivity and uncertainty analysis with recent cross section covariance data for criticality safety code and data validation. The use of sensitivity and uncertainty analysis provides for the assessment of a defensible computational bias, bias uncertainty, and gap analysis for a complex system that otherwise could be assessed only through the use of expert judgment and conservative assumptions.