A self-revealing finding was identified for the failure of operators to maintain configuration control of valves during an air pressure test of a repair of a
feedwater heater. Specifically, the operators left valve RD198 open during a pressure test of the
extraction steam, or shell side, of
feedwater heater 1-5 of the Main
Feedwater System. This loss of configuration control gave testing air a path to the
main condensers and led to degradation of the condenser vacuum, which then caused the Integrated Control System to raise reactor power unexpectedly. No violation occurred. Once the issue was identified, the licensee stopped the air pressure test and entered the finding into their corrective action program. The finding is greater than minor since it was associated with the configuration controloperating equipment lineup attribute of the
Initiating Events Cornerstone and because it affected the associated cornerstone objective to limit the likelihood of those events that upset plant stability during power operations. The finding is of very low safety significance since it did not contribute to the likelihood of a primary or secondary system loss of coolant accident, did not contribute to both the likelihood of a
reactor trip and the likelihood that mitigating equipment or functions would not be available, and did not increase the likelihood of a fire or internal/external flood. The finding was associated with the cross-cutting area of human performance in that work control and specifically the coordination of work activities did not properly record or assess the status of a valve in the test boundary and created a condition that had an operational impact (
H.3(b)). (Section 4OA3
