05000271/FIN-2014004-01
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Finding | |
|---|---|
| Title | Failures to Promptly Identify Through-Wall Leakage from Service Water Piping to the Emergency Diesel Generators |
| Description | The inspectors identified a Green NCV of 10 CFR 50, Appendix B, Criterion XVI, Corrective Action, because Entergy did not promptly identify conditions adverse to quality related to the service water system. Specifically, observable through-wall leaks that were reasonably able to be identified existed in service water piping supplying the emergency diesel generators (EDGs) cooling system for an extended period of time without being identified. In addition, the affected service water piping was not appropriately scheduled for treatment and replacement given known conditions favorable to microbiologically induced corrosion (MIC). Entergys corrective actions to restore compliance consisted of performing complete walkdowns of all accessible safety-related service water piping, performing ultrasonic inspections of the three leak locations and fifteen extent of condition locations, conducting structural analyses to determine structural integrity of the piping with the measured thinning, and performing daily leak rate monitoring and frequent periodic ultrasonic inspections of no more than 30 day intervals. This finding is more than minor because if left uncorrected it has the potential to lead to a more significant safety concern. Specifically, the through-wall leaks were unmonitored degraded conditions with reasonable doubt on the operability of the service water and alternate cooling systems before the results of ultrasonic inspections and new structural analyses were obtained. The inspectors determined the significance of the finding using IMC 0609, Appendix A, The Significance Determination Process (SDP) for Findings At- Power. The finding was determined to be of very low safety significance (Green) because the finding was a deficiency affecting the design and qualification of the service water and alternate cooling systems and the systems maintained their operability. The inspectors determined that the finding has a cross-cutting aspect in the area of Human Performance, Resources, because Entergy did not ensure that the combination of piping replacements, chemical treatments, guidance and procedures for walkdowns, and camera coverage were adequate to support nuclear safety. |
| Site: | Vermont Yankee  |
|---|---|
| Report | IR 05000271/2014004 Section 1R04 |
| Date counted | Sep 30, 2014 (2014Q3) |
| Type: | NCV: Green |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.04 |
| Inspectors (proximate) | E Burket J Schoppy N Day N Floyd R Mckinley S Barr S Rich S Rutenkroger T Fish T O'Hara |
| Violation of: | 10 CFR 50 Appendix B Criterion XVI |
| CCA | H.1, Resources |
| INPO aspect | LA.1 |
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Finding - Vermont Yankee - IR 05000271/2014004 | |||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Vermont Yankee) @ 2014Q3
Self-Identified List (Vermont Yankee)
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