THE HEALTH OF RISK-INFORMED REGULATION

Ten years ago, risk-informed regulation was proclaimed by many to be the future of regulatory activity. The three options for using risk in the regulatory arena had been defined in SECY-98-300 and efforts were initiated to develop the first regulatory changes. However, regulatory change has been slow. The revised 50.44 rule, which was supposed to be non-controversial, was not finalized until September of 2003, five years after it was started. The new 50.69 rule, which embodied the STP graded quality assurance principles, was not finalized until November of 2004 and the Pressurized Water Reactor Owners Group (PWROG) pilot plant application is still under review by the Nuclear Regulatory Commission (NRC). The 50.46a rule change, admittedly a very difficult and controversial undertaking, is still not finalized. On the other hand, the NRC has increased the use of plant risk insights and results the Significance Determination Process (SDP) and the Mitigating System Performance Index (MSPI). While the industry has been working on the major regulatory initatives described above, they have also successfully initiated a significant number of risk-informed programs within the existing regulations. Significant among these industry efforts are the risk-informed changes to the Technical Specifications and the risk-informed changes to in service inspection and in-service testing. One bright spot on the horizon is the use of NFPA-805, which uses fire risk insights, as an alternative to the Appendix R requirements for fire protection. The industry and the NRC are working together to develop an acceptable methodology for implementing this alternative. The increasing requirements for scope and quality of the probabilistic risk assessments (PRAs) that are used as the basis for many risk-informed activities has resulted in a major slow-down in licensee implementation of new risk-informed activites. The publication of industry consensus standards is resulting in significant resource expenditures to upgrade the scope and quality of the PRAs. Once the scope and quality of the plant-specific PRAs is completed, there should again be significant implementation of risk-informed applications. In summary, risk-informed regulation has already produced significant increases in safety and has potentially reduced licensee regulatory burdens. However, the promise of risk-informed changes to regulations is still an unfilfilled expectation and will likely remain so in the near future. Once the scope and quality of PRAs is upgraded to satisfy the industry consensus standards, there should be renewed activity in implenting risk-informed programs.