A self-revealing finding was identified for
FENOCs failure to perform maintenance on the Unit 2
feedwater heater drain system in accordance with
FENOCs maintenance process, NOP-WM-4006, Conduct of Maintenance. Specifically,
FENOC did not adjust the A first point
feedwater heater normal and high level control valve (
LCV) controllers to their specified setpoints. As a result, the A heater and separator drain pumps tripped and this led to an unplanned power reduction from 100 percent to 60 percent reactor power on April 12, 2015.
FENOCs corrective action included adjusting the setpoints of the
LCV controllers to their specified setpoints and entering the issue into their corrective action program as condition report 2015-05088. The performance deficiency was more-than-minor because it was associated with the Configuration Control attribute of the
Initiating Events cornerstone, and adversely affected the cornerstone objective of limiting the likelihood of events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. Additionally, the performance deficiency was similar to example 4.b in
IMC 0612 Appendix E, in that failing to follow procedure caused a reactor
transient. This finding was determined to be of very low safety significance (Green) because it did not cause a
reactor trip and the loss of mitigation equipment. This finding has a cross-cutting aspect in the area of Human Performance, Training, because
FENOC failed to ensure knowledge transfer to maintain a knowledgeable, technically competent workforce and instill nuclear safety values. Specifically,
FENOC did not ensure that knowledge was adequate to perform maintenance on the A first point
feedwater heater
LCVs [H.9].
