Regulatory analyses for severe accident issues: an example

A study has been performed as part of a program to establish methods for incorporation of information from a broad range of research programs, particularly those which generate probabilistic risk information, and to develop suitable presentation formats for providing guidance to decisionmakers on issues related to severe accidents. The study addresses issues related to information availability, content, and presentation formats for use in the regulatory decisionmaking process. The approach employed to address these issues was to perform an example regulatory analysis on representative topics of interest using available technical information. The issue examined in the example analysis is the implementation of either a vented containment system or an alternative decay heat removal system at the Peach Bottom No. 2 plant. The example demonstrates many of the problems which will be encountered as probabilistic information from ongoing programs is incorporated into the regulatory decisionmaking process