A self-revealing non-cited violation (
NCV) was identified for a human performance error associated with failure of an operator to verify that the discharge valve on the Nuclear Service Cooling Water (
NSCW) pump #5 went closed after securing the pump as required by the operating procedure. As a result,
NSCW pump #5 was rendered
inoperable for several hours. Licensee immediately effected repairs to the discharge valve
MOV and returned the
NSCW pump #5 to
operable status. This issue is more than minor because it is associated with a cornerstone attribute and adversely affected the objective of the
Mitigating Systems cornerstone. Specifically, the performance deficiency is a human performance error which affected the availability, reliability, and capability of the A train
emergency core cooling system to respond to a loss of coolant accident. The finding was determined to be of very low safety significance (Green) because the event did not represent an actual loss of safety function of a single train for greater than its TS allowed outage time. The inspectors determined that the cause of this finding was related to the Work Practices component of the Human Performance cross-cutting area due to less-than-adequate human error prevention techniques
H.4(a). Specifically, self checking techniques were less than adequate
