05000271/FIN-2013004-01
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Finding | |
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Title | Failure to Monitor the Unavailability of the B Control Rod Drive Equipment Train |
Description | The inspectors identified a NCV of Title 10 Code of Federal Regulations (10 CFR) 50.65, Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants, because Entergy did not monitor the performance of the B control rod drive (CRD) equipment train. Specifically, Entergy did not include seven days of unavailability for the B CRD flow control valve in the tracking database, and therefore did not initiate corrective actions when the train exceeded its unavailability criterion. Entergy initiated a condition report to document exceeding the performance criterion, entered the unavailability into the tracking database, and initiated a condition report to document the oversight in unavailability tracking. This finding is more than minor because it is associated with the human performance attribute of the Mitigating Systems cornerstone and affected the cornerstone objective of ensuring the availability of systems that respond to initiating events to prevent undesirable consequences. Specifically, since Entergy personnel did not recognize that this unavailability put the plant into a higher integrated risk category and did not recognize the plant risk impact of the flow control valves extended unavailability, no corrective actions were taken to address the maintenance practices which caused the unavailability performance criterion to be exceeded unnecessarily. In accordance with IMC 0609.04, Initial Characterization of Findings, and Exhibit 2 of IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power, issued June 19, 2012, the inspectors determined that this finding is of very low safety significance (Green) because the performance deficiency did not represent a loss of system safety function or a loss of safety function of a single train for greater than its Technical Specification allowed outage time. In addition, the failure to recognize and manage the plant risk associated with the 169 hours0.00196 days <br />0.0469 hours <br />2.794312e-4 weeks <br />6.43045e-5 months <br /> of unavailability of the B CRD flow control valve resulted in an incremental core damage probability of approximately 2E-10, which is less than 1E-6, and therefore also of very low safety significance. The inspectors determined that this finding has a cross-cutting aspect in the Human Performance area, Work Practices component, because Entergy personnel did not follow the maintenance rule program procedures. Specifically, operations did not log the unavailability in the maintenance rule out-of-service log and the system engineer did not review the scoping document to verify which components counted toward the train unavailability. |
Site: | Vermont Yankee ![]() |
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Report | IR 05000271/2013004 Section 1R12 |
Date counted | Sep 30, 2013 (2013Q3) |
Type: | NCV: Green |
cornerstone | Mitigating Systems |
Identified by: | NRC identified |
Inspection Procedure: | IP 71111.12 |
Inspectors (proximate) | S Rutenkroger J Schoppy J Furia T Burns R Clagg R Mckinley S Rich J Deboer |
Violation of: | Technical Specification - Procedures 10 CFR 50.65 Technical Specification |
CCA | H.8, Procedure Adherence |
INPO aspect | WP.4 |
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Finding - Vermont Yankee - IR 05000271/2013004 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Vermont Yankee) @ 2013Q3
Self-Identified List (Vermont Yankee)
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