05000334/FIN-2013004-01
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Finding | |
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Title | Licensee-Identified Violation |
Description | The Beaver Valley Power Station Unit 2 Technical Specification limiting condition for operation (LCO) 3.5.2 requires two trains of emergency core cooling system (ECCS) to be operable in Modes 1, 2, and 3. Contrary to the above, on June 17, 2013 to June 24, 2013, FENOC failed to have two trains of ECCS operable in Mode 1 which existed for greater than the allowed restoration and shutdown completion times of the LCO due to inadequate procedures that resulted in gas voids in the 21C high head safety injection pump (HHSI) suction piping while the 21A HHSI pump was inoperable due to planned maintenance. FENOC corrective actions include increased void monitoring frequency and updating fill and vent procedures for the HHSI system (CR 2013-09725). In accordance with IMC 0609 Attachment 4, Initial Characterization of Findings, and Exhibit 2 of IMC 0609 Appendix A, The Significance Determination Process for Findings at Power, the inspectors identified that the finding screened as potentially risk-significant due to representing an actual loss of function of a single train for greater than its technical specification allowed outage time. Therefore, a detailed analysis was conducted utilizing the Beaver Valley Unit 2 SPAR model, version 8.23 run by SAPHIRE version 8.0.9. The 21C is a spare pump that can be manually aligned to either train. As a result the analysis considered cases in which it was in the standby configuration and also when it would be required to be manually realigned and started. The first case had a fault exposure time of 204 hours0.00236 days <br />0.0567 hours <br />3.373016e-4 weeks <br />7.7622e-5 months <br /> and was assumed to have the pump fail to start if called upon. The second condition had an exposure time of 185 hours0.00214 days <br />0.0514 hours <br />3.058862e-4 weeks <br />7.03925e-5 months <br /> and was assumed to fail if realigned. The increase in risk from these conditions resulted in a change in core damage frequency of less than 1E-7. The dominant sequence was a loss of containment air along with failures of reactor coolant pump seals, the ability to provide high pressure injection and the failure of secondary side heat removal. Because an increase in core damage frequency was less than 1E-7, further evaluation of external event and large early release risk was not required and the results calculated were determined to be of very low safety significance (Green). |
Site: | Beaver Valley |
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Report | IR 05000334/2013004 Section 4OA7 |
Date counted | Sep 30, 2013 (2013Q3) |
Type: | NCV: Green |
cornerstone | Mitigating Systems |
Identified by: | Licensee-identified |
Inspection Procedure: | |
Inspectors (proximate) | D Kern D Spindler E Burket E Carfang G Hunegs J Laughlin J Piotter J Tomlinson N Floyd S Hammann T Fish T Moslak |
Violation of: | Technical Specification - Procedures Technical Specification |
INPO aspect | |
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