05000286/FIN-2008005-03
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Finding | |
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Title | Technical Specification Prohibited Condition Due to Exceeding the Allowed Completion Time for an Inoperable Safety Injection Pump Caused by a Failed Motor Supply Breaker. |
Description | On January 27, 2008, during an attempt to start the 31 Safety Injection Pump (SIP), the 31 SIP failed to start. Entergy staff investigated the failure to start and determined that the power supply breaker for the pump motor failed to close. Technical Specification (TS) 3.5.2, Emergency Core Cooling Systems (ECCS), Condition A was entered for one or more trains inoperable. Entergys review of past operation of the 31 SIP determined that the pump was last operable on January 11, 2008. TS 3.5.2 requires three trains of ECCS to be operable. The required action A.1 for TS 3.5.2, Condition A, is to restore the train(s) to operable within a completion time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The inoperable condition based on past operation exceeded the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed completion time for TS 3.5.2 with the required action not completed. Entergy determined the cause of the breaker problem was due to the breaker closing springs not charging. The closing springs did not charge properly due to a dislodged charging motor brush assembly because a retaining screw became loose. Entergys corrective actions included replacement of the breaker spring charging motor and subsequent breaker testing, and the breaker was returned to service on January 27, 2008. Entergy also revised the breaker maintenance procedure to require inspection of the breaker motor retaining screw. The inspectors reviewed the LER and Entergys evaluation of the event and associated corrective actions contained in CR-IP-2008-00252. The inspectors determined that the problem with the 31 SIP breaker, specific to the closing springs, was not within Entergys ability to foresee and correct based on review of the breakers maintenance and operational history, equipment configuration, and available operating experience information. Specifically, the inspectors determined that Entergys maintenance performed on this breaker was appropriate and up to date consistent with station and vendor instructions. The inspectors determined that, based on review on the operational history of the breaker, there was not information that indicated a potential reliability challenge related to the closing spring. The inspectors also determined that operating experience information available to Entergy did not identify the potential for the closing spring problem that was evidenced for this type of breaker. Further, the inspectors concluded that, due to the installed location of the charging motor brush assembly, Entergys routine processes and procedures would not have identified or reasonably detected the failure. Therefore, the inspectors determined this equipment failure could not have been avoided or detected by Entergys quality assurance program or other related control measures and did not constitute a performance deficiency. Additionally, based on the assumption that the 31 SIP was inoperable for 16 days, the inspectors performed a Phase 2 SDP analysis that resulted in the risk significance of this issue as being of very low safety significance (Green). The inspectors determined that the 31 SIP being inoperable for greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> was a violation of Entergys Technical Specification 3.5.2, Emergency Core Cooling System (ECCS), Condition A, which requires an inoperable train of safety injection to be restored to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. However, because there was no performance deficiency identified and the risk significance is of very low safety significance, the NRC has chosen to exercise enforcement discretion and refrain from issuing enforcement action for this violation of NRC requirements in accordance with Section VII.B.6 of the NRCs Enforcement Policy. Further, because Entergys actions did not contribute to this violation, it will not be considered in the assessment process or NRCs action matrix. |
Site: | Indian Point |
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Report | IR 05000286/2008005 Section 4OA3 |
Date counted | Dec 31, 2008 (2008Q4) |
Type: | Violation: Green |
cornerstone | Mitigating Systems |
Identified by: | NRC identified |
Inspection Procedure: | IP 71153 |
Inspectors (proximate) | A Koonce A Rosebrook B Haagensen C Hott D Silk G Malone J Commiskey J Noggle M Gray P Cataldo R Fuhrmeister |
INPO aspect | |
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Finding - Indian Point - IR 05000286/2008005 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Indian Point) @ 2008Q4
Self-Identified List (Indian Point)
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