This 60-day telephone notification is being made under reporting requirements specified by
10 CFR 50.73(a)(2)(iv)(A) and
10 CFR 50.73(a)(1) to describe an invalid actuation of the Unit 1 11
RHR Pump while Unit 1 was at NO MODE. It was a complete actuation. This was not the result of a preplanned sequence during testing and the system was not removed from service.
At 0340 CDT on October 26, 2014, the Unit 1 11 RHR Pump was noted to have started while investigating an NSSS [nuclear steam supply system] annunciator system ground. The operator verified that the pump had adequate suction path via the RCS Cold Leg and stable pump discharge pressure. The 11 RHR Pump was stopped per the plant's abnormal operating procedure.
Evaluation of this event has shown that the auto-start of 11 RHR pump was due to a human performance error while performing relay replacements.
Following troubleshooting of the auto-start and completion of the relay maintenance, the 11 RHR pump was run; the pump and system operated properly. The health and safety of the public was not affected by this issue.
The licensee has notified the NRC Resident Inspector.
