05000333/FIN-2008005-02
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Finding | |
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Title | Conduct of Relay Test Without Plant Impact Review Resulted in Loss of Emergency Bus and Shutdown Cooling |
Description | A self-revealing NCV of 10 CFR Part 50.65 (a)(4), Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants, was identified when Entergy did not manage the increase in risk during the conduct of relay testing associated with emergency buses. The conduct of the relay testing resulted in an unanticipated loss of shutdown cooling (SDC) function. Entergy implemented corrective actions that included communicating the error to personnel to reinforce management expectations for control of protected equipment and providing an additional level of work authorization review. This finding is more than minor because it is associated with the Mitigating Systems cornerstone and is related to Entergys performance in assessing and managing risk. A risk assessment review was not conducted prior to performance of a trip and lockout relay functional test associated with emergency buses. Specifically, this finding reflects inadequate risk management that contributed to a short duration loss of shutdown decay heat removal capability resulting from the inadvertent interruption of flow through the operating train of shutdown cooling with the plant in a cold shutdown condition. This was reasonably within Entergys ability to foresee and prevent because there were opportunities to recognize and manage the potential risk of losing shutdown cooling and to schedule the maintenance activity at a more appropriate maintenance window or take actions to prevent the loss of shutdown cooling. In accordance with IMC 0609, Attachment 0609.04, Phase 1 Initial Screening and Characterization of Findings, and Appendix G, Shutdown Operations Significance Determination Process, the inspectors determined that this finding was of very low safety significance (Green). The basis for this determination is that in accordance with IMC 0609, Appendix G, Table 1, Losses of Control, and Checklist 8, BWR Cold Shutdown or Refueling Operation Time to Boil > 2 Hours: RCS Level <23 feet Above Top of Flange, this finding did not require quantification and did not constitute a significant loss of thermal margin, based upon the slow reactor coolant system heat-up rate and minimal time of interruption in shutdown cooling system operation. The problem was entered into Entergys corrective action program as CR-JAF-2008-03805. The inspectors determined that this finding had a cross-cutting aspect in the area of human performance because Entergy did not plan and coordinate work activities properly to manage the operational impact of work activities. Specifically, Entergy did not recognize that the emergency bus 10600 would be de-energized as a result of the trip and lockout relay functional test. (H.3(b)) (Section 1R20 |
Site: | FitzPatrick ![]() |
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Report | IR 05000333/2008005 Section 1R20 |
Date counted | Dec 31, 2008 (2008Q4) |
Type: | NCV: Green |
cornerstone | Mitigating Systems |
Identified by: | Self-revealing |
Inspection Procedure: | IP 71111.2 |
Inspectors (proximate) | S Rutenkroger G Hunegs R Fuhrmeister M Gray A Rosebrook |
CCA | H.5, Work Management |
INPO aspect | WP.1 |
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Finding - FitzPatrick - IR 05000333/2008005 | ||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (FitzPatrick) @ 2008Q4
Self-Identified List (FitzPatrick)
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