05000382/FIN-2011003-03
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Finding | |
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| Title | Failure to Implement Written Procedures for Restoring a Time Delay Relay Associated with the A Output Breaker |
| Description | A self-revealing noncited violation of Technical Specification 6.8.1.a occurred because the licensee did not implement written procedures and work order instructions. Specifically, maintenance personnel did not follow Procedure ME-007-005, Time Delay Relay Setting Check, Adjustment, and Functional Test , during the lifting leads process for restoration of a time delay relay (EG EREL2327-C) associated with an A emergency diesel generator (EDG) maintenance activity. As a result, the A EDG output breaker did not automatically close during technical specification surveillance testing because the leads on the relay were wired incorrectly. The licensee entered this issue into their corrective action program for resolution as CR-WF3-2011-3190. The immediate corrective action included the re-wiring of the relay to allow the A EDG to automatically close to the safety-related bus. The finding was more than minor because it was associated with the human and equipment performance attributes of the Mitigating Systems Cornerstone and affected the cornerstone objective to ensure the availability, reliability and capability of systems that respond to initiating events to prevent undesirable consequences (i.e., core damage). Specifically, the licensee did not ensure the availability, reliability and capability of the A EDG through the use of human error prevention techniques. The inspectors performed the initial significance determination for the diesel generator output breaker failure. The inspectors used the NRC Inspection Manual Chapter 0609, Attachment 0609.04, Phase 1 Initial Screening and Characterization of Findings. The finding screened to a Phase 2 significance determination because it involved a potential loss of one train of safety related equipment for longer than the technical specification allowed outage time. A Region IV senior reactor analyst performed a Phase 2 significance determination and used the pre-solved worksheet from the Risk Informed Inspection Notebook for the Waterford-3 Nuclear Power Plant, Revision 2.01a. The senior reactor analyst considered the output breaker a part of the emergency diesel generator component boundary. Assuming a one year exposure period, the finding was potentially Yellow, which warranted further review. Therefore, the senior reactor analyst performed a bounding Phase 3 significance determination. The analyst determined that the finding was of very low safety significance (Green). The bounding change to the core damage frequency was approximately 5.4E-7/year. The dominant core damage sequences included loss of offsite power events, failure of the output breaker recovery action, independent failure of the other emergency diesel generator and failure to recover offsite power in 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. Equipment that helped mitigate the risk included the ability of an operator to recover the output breaker. The finding had a crosscutting aspect in the work practices component of the human performance area because the licensee did not communicate human performance error prevention techniques, such as self and peer checking, and proper documentation of activities. |
| Site: | Waterford  |
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| Report | IR 05000382/2011003 Section 1R19 |
| Date counted | Jun 30, 2011 (2011Q2) |
| Type: | NCV: Green |
| cornerstone | Mitigating Systems |
| Identified by: | Self-revealing |
| Inspection Procedure: | IP 71111.19 |
| Inspectors (proximate) | D Overland S Makor N Greene C Smith P Elkmann M Davis L Carson R Azua |
| CCA | H.12, Avoid Complacency |
| INPO aspect | QA.4 |
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Finding - Waterford - IR 05000382/2011003 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Waterford) @ 2011Q2
Self-Identified List (Waterford)
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