The inspectors identified a non-cited violation of
10 CFR Part 50, Appendix B, Criterion XVI because the licensee did not promptly identify and correct a
condition adverse to quality associated with the B emergency
feedwater backup control valve EFW-223B. Specifically, the licensee did not promptly identify and correct internal leakage from tears in the EFW-223B actuator
diaphragm. As a result, these internal tears in the
diaphragm caused excessive leakage that affected two
nitrogen accumulators used to operate EFW-223B and other safety related valves. The licensee entered this issue into their corrective action program as
CR-WF3-2012-0860. The immediate corrective actions taken to restore compliance included the replacement of the
diaphragm and to determine the extent of condition for other air-operated valves with the same type, make, and model
diaphragm. The planned corrective action included the revision of the air operated valve program post maintenance tests to identify similar problems. The failure to promptly identify and correct tears in the internal actuator
diaphragm of the B emergency
feedwater backup control valve EFW-223B was a performance deficiency. The performance deficiency was more than minor because it was associated with the equipment performance attribute of the Mitigating System Cornerstone and affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to
initiating events to prevent undesirable consequences. Specifically, the internal leakage of EFW-223B affected two safety-related
nitrogen accumulators and their ability to provide
nitrogen gas to other connected safety related valves following a loss of offsite power event. The inspector used the NRC Inspection Manual 0609, Attachment 4, Initial Characterization of Findings, to evaluate this issue. The finding required a detailed analysis because it involved a potential loss of one train of safety related equipment for longer than the technical specification allowed outage time. Therefore, a senior reactor analyst performed a bounding detailed risk evaluation. The analyst determined that the finding is of very low safety significance (Green) because the bounding change to the core damage frequency is less than
1E-9 per year. The inspectors concluded that the finding reflected current licensee performance and involved a cross-cutting aspect in the corrective action program component of the problem identification and resolution area in that the licensee did not thoroughly evaluate problems such that the resolutions address causes and extent of conditions, as necessary
