05000280/FIN-2012007-01
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Finding | |
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| Title | |
| Description | The inspectors identified one Apparent Violation (AV) of Surry Units 1 and 2 Technical Specification 6.4.A.7 for the failure to provide detailed written procedures with appropriate check-off lists and instructions for preventive or corrective maintenance operations which would have an effect on the safety of the reactor. Degradation of the reactor coolant system (RCS) standpipe could impact the safety of the reactor. This AV has been determined to be of very low safety significance (Green) for Unit 1 and of low to moderate safety significance (Preliminary White) for Unit 2. Specifically, a performance deficiency was identified in that the licensee failed to review the Vendor Technical Manual (VTM) for the RCS standpipe to determine conformance with established maintenance practices as required by Dominion Procedure VPAP 0602,Vendor Technical Manual Control. As a result, the licensee did not evaluate the need for a periodic maintenance activity associated with the standpipe or if current maintenance practices were adequate in both scope and frequency. The licensee entered this issue into their corrective action program as condition report 460261. The inspectors determined that the failure to review the VTM as required by VPAP-0602 was a performance deficiency that was within the licensees ability to foresee and correct and which should have been prevented. The inspectors reviewed NRC Inspection Manual Chapter (IMC) 0612, Appendix B, issued on 12/24/2009, and determined that the finding was more than minor because it could adversely impact the equipment performance attribute of the initiating events cornerstone objective to limit the likelihood of those events that upset plant stability and challenge critical safety functions during shutdown operations. Specifically, the performance deficiency led to the degradation of the standpipe internals, which contributed to both decreased standpipe reliability during a high risk reduced inventory configuration and the performance of multiple subsequent entries into that configuration. These activities related to the safety of reactor. Because the finding affected the safety of a reactor during shutdown or refueling outages, the inspectors evaluated this finding in accordance with IMC 0609 Appendix G, Shutdown Operations Significance Determination Process, Attachment 1, Checklist 3 PWR Cold Shutdown and Refueling Operation - RCS Open and Refueling Cavity Level < 23 or RCS Closed and No Inventory in Pressurizer Time to Boiling < 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />. The inspectors determined that the Unit 1 finding was low safety significance (Green) because no actual RCS standpipe level indication problems were observed during its reduced inventory periods. The Unit 2 finding required a Phase 3 analysis because the licensee did not maintain two sources of continuous level instrumentation with the pressurizer empty in accordance with checklist item II.A.(2) at the times, where the standpipe main control room (MCR) indication became erratic and had to be declared nonfunctional. As a result, additional drain-down evolutions were required to perform the valve repairs. Thus, the Unit 2 finding resulted in an increase in the likelihood of a loss of RCS inventory and required a significance determination process (SDP) Phase 2/3 evaluation. The NRC performed a SDP Phase 3 evaluation based on the best available information and preliminarily determined this finding to be of low to moderate safety significance (Preliminary White) for Unit 2, which may require additional NRC inspections. The analysis estimates the increase in risk from the additional drain-down evolutions and extra time in mid-loop; i.e., the risk above what the repair action would have represented without the performance deficiency. The analysis determined that risk increase to be on the order of 4E-06, which is low to moderate safety significance, White. Influential assumptions, dominant cut-set contributors, exposure time, uncertainty and sensitivity analysis, and SDP Phase 3 evaluation results are discussed in the Enclosure 2 of this report. The cause of this finding did not involve a cross-cutting aspect because it is not indicative of current licensee performance because of the time period associated with the receipt of the VTM and its revisions (2002-2003). |
| Site: | Surry  |
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| Report | IR 05000280/2012007 Section 4OA5 |
| Date counted | Mar 31, 2012 (2012Q1) |
| Type: | NCV: Green |
| cornerstone | Initiating Events |
| Identified by: | NRC identified |
| Inspection Procedure: | |
| Inspectors (proximate) | G Macdonald G Mccoy J Nadel R Clagg S Ninh S Sanchez |
| INPO aspect | |
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Finding - Surry - IR 05000280/2012007 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Surry) @ 2012Q1
Self-Identified List (Surry)
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