05000348/FIN-2009005-02
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Finding | |
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Title | Failure to Implement Maintenance Inspections of Safety-Related Switchgear |
Description | A self-revealing NCV of TS 5.4, Procedures, was identified for the failure to implement preventative maintenance inspections on the 1-2L 600 volt load center as specified by FNP-0-EMP-1322.10, Maintenance and Cleaning of Westinghouse Switchgear. The failure to perform the specified inspections on the 1-2L 600 volt load center allowed bus fastener torque to degrade to the point that bus bar damage occurred which rendered the 1-2L 600 volt load center inoperable. The licensee has entered the issue into the CAP as CR 2008103720. The licensee has completed corrective actions to restore operability of the 1-2L 600 volt load center and schedule the specified maintenance inspections. The failure to implement preventative maintenance inspections on the 1-2L 600 volt load center as specified by FNP-0-EMP-1322.10 was a performance deficiency. This finding was more than minor because it adversely affected the equipment performance attribute of the mitigating systems 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 finding resulted in the potential loss of SW cooling due to 1-2L 600 V load center inoperability. This finding was assessed using the mitigating systems cornerstone column of the Phase 1 screening worksheet of the SDP and determined to require a Phase 3 analysis because the finding represented the actual loss of a safety function of a single train for greater than its allowed TS outage time. A senior reactor analyst performed a Phase 3 evaluation under the SDP and determined that the finding was of very low safety significance (Green). The dominant accident sequence was a failure of train A service water (SW) due to loss of the 4KV F bus, failure of the B train due to loss of the pump cooling sub-system and loss of the 600 VAC load center 1/2L due to the performance deficiency causing a total loss of service water to the unit. Auxiliary feedwater (AFW) provided secondary side cooling, but without SW both reactor coolant pump (RCP) seal cooling sources, component cooling water (CCW) thermal barrier cooling & high head safety injection/charging seal injection, failed. Consequently, a seal loss of coolant accident happened without the ability to makeup to the reactor coolant system resulting in core damage. This finding is associated with a cross-cutting aspect in the work control component of the human performance area in that the repetitive task to perform procedure FNP-0-EMP-1322.10 was never entered into the work control process (H.3(b)) |
Site: | Farley |
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Report | IR 05000348/2009005 Section 1R12 |
Date counted | Dec 31, 2009 (2009Q4) |
Type: | NCV: Green |
cornerstone | Mitigating Systems |
Identified by: | Self-revealing |
Inspection Procedure: | IP 71111.12 |
Inspectors (proximate) | E Crowe S Shaeffer W Rogers G Macdonald B Caballero S Sandal |
CCA | H.5, Work Management |
INPO aspect | WP.1 |
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Finding - Farley - IR 05000348/2009005 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Farley) @ 2009Q4
Self-Identified List (Farley)
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