This 60-day optional report as allowed by 10 CFR 50.73(a)(1), is being made under the reporting requirement in 10 CFR 50.73(a)(2)(iv)(A) to describe an
invalid actuation of a specified system, specifically the
Auxiliary Feedwater (
AFW) system. On December 22, 2012 at 0142, with Unit 1 in Mode 4, the 1A
AFW pump automatically started due to failure to reset the signal created when the 1B
Feedwater Pump was tripped for testing. The 1A
feedwater pump was already in the 'tripped' condition when the 1B
feedwater pump was tripped, resulting in an auto start signal being generated for the
AFW system. Both trains of the
AFW had the auto start defeat instated at the time of the testing of the 1B
Feedwater pump, blocking the start signal. During subsequent alignment of the
AFW for standby readiness, the auto start defeat was removed from the 1A
AFW system without resetting the system to remove the signal generated during the 1B
Feedwater pump testing, resulting in the actuation of the system. The 1B
Feedwater Pump had been reset and was in service therefore the signal associated with the trip of both
feedwater pumps was not consistent with the actual plant conditions at the time that the auto start defeat was removed from the 1A
AFW system. Following the auto start of the 1A motor driven
AFW pump, operators confirmed the 1A
AFW train experienced a complete actuation and that the 1A
AFW Pump and its associated valves functioned as designed. The pump was subsequently secured and the
AFW system was returned to standby readiness. This event was entered into the site specific correction action program for resolution.
The NRC Resident Inspector has been informed. The licensee will notify the states of
North Carolina and
South Carolina. Additionally the licensee will notify York, Gaston, and Mecklenburg County.
