Search Options | ||||
Index | Site Map | FAQ | Facility Info | Reading Rm | New | Help | Glossary | Contact Us |
July 21, 1999 The Honorable Greta Joy Dicus Dear Chairman Dicus: SUBJECT: PROPOSED REVISION 3 TO REGULATORY GUIDE 1.160 (DG-1082), "ASSESSING AND MANAGING RISK BEFORE MAINTENANCE ACTIVITIES AT NUCLEAR POWER PLANTS" During the 464th meeting of the Advisory Committee on Reactor Safeguards, July 14-16, 1999, we reviewed the proposed Revision 3 to Regulatory Guide 1.160 (DG-1082), "Assessing and Managing Risk Before Maintenance Activities at Nuclear Power Plants." During our review, we had the benefit of discussions with representatives of the NRC staff and the Nuclear Energy Institute (NEI). We also had the benefit of the documents referenced. Recommendations and Conclusion
Discussion The staff has made revisions to Regulatory Guide 1.160 since our previous discussion and our report dated May 11, 1999. Although some of the revised language has improved this Guide, we believe that further revisions as noted in our recommendations are needed. During our meeting, we were informed by NEI that a revision to Section 11 of the NUMARC 93- 01 document would be forthcoming. Both we and the staff need to review the revised section to determine its acceptability for endorsement by Regulatory Guide 1.160, Revision 3. Determining the risk significance of the plant configurations that may be encountered during maintenance and the large number of combinations of SSCs that may be out of service could require a large amount of resources. We believe that the four conditions set forth in Section 5 reasonably bound the number of configurations that must be considered. We encourage the staff to provide more guidance for determining the importance of multiple SSCs being out of service during maintenance. Such guidance is available in the literature (Reference 3). We commend the staff for its efforts to revise the Maintenance Rule to better manage risk during maintenance activities and look forward to the resolution of our comments on the proposed Revision 3 to Regulatory Guide 1.160. Sincerely, /s/ Dana A. Powers References
|