The inspector identified a
NCV of
10 CFR Part 50, Appendix B, Criterion XVI, Corrective Action, for failure to determine the cause of a significant
condition adverse to quality and take corrective action to preclude repetition. On October 22, 2009, the plant received multiple alarms for the A
EDG due to actuation of speed control relays while in a standby condition. This condition would have prevented an automatic start of the A
EDG. The licensees handling of this issue had the following problems: the failure was entered into the
CAP, but the licensee failed to recognize that this was a significant
condition adverse to quality; the initial evaluation failed to identify that the cause of the failure was a circuit design error, and therefore the licensee failed to implement appropriate action to prevent recurrence; the extent of condition review failed to identifiy that the Turbine Driven
Auxiliary Feedwater Pump (TDAFWP) was also affected; prior indications of the failure mechanism had not been entered into the
CAP; and multiple examples of failure to follow the corrective action process contributed to not finding the actual cause sooner. This was entered into the licensees
CAP as CR 65323 The failure to determine the cause of a significant
condition adverse to quality and take corrective action to preclude repetition was a performance deficiency. The performance deficiency was more than minor because it was associated with the equipment performance attribute of the
Mitigating Systems Cornerstone and affected the cornerstone objective. Specifically, the failure to determine the cause and take effective corrective action for electrical noise that impacted the
EDG speed switches resulted in the degraded condition continuing to exist for over two years after the initial failure. The inspector determined that the finding was of very low safety significance (Green) because the finding was a deficiency affecting the design or qualification of a mitigating structure, system, or component (
SSC), but the corrective actions that were implemented were sufficient to ensure that the
SSC maintained its operability and functionality. The NRC determined the finding had a cross cutting aspect in the human performance area associated with decision-making - systematic processes because the licensee did not make safety-significant or risk-significant decisions using a systematic process when they evaluated the cause of the diesel generator failure
