The inspectors identified a Green self-revealing finding for the failure of maintenance personnel to adequately adjust bearing oil pressure to a Unit 2 main
feedwater pump. This caused the main
feedwater pump to trip, which subsequently caused an unplanned power reduction. The overhaul procedure used by the machinists, SO23-I-8.165, Feed Pump Drive Turbine Internal, Bearing, and Valve Inspection, Revision 11, only stated to adjust pressures as required. This finding was entered into the licensees corrective action program as
AR 080101431. The finding was more than minor because it affects the
Initiating Events cornerstone objective to limit the likelihood of those events that upset plant stability and challenge critical safety functions during power operations. Using Manual Chapter 609,
Significance Determination Process, Phase 1 worksheet, the finding was determined to have very low safety significance (Green) because the finding did not contribute to both the likelihood of a
reactor trip and the likelihood that mitigation equipment or functions would not be available. The finding had a crosscutting aspect in the area of human performance associated with the work practices (
H.4(a)) in that human error prevention techniques, such as proper documentation, were not implemented, and that maintenance personnel proceeded with the work activity when faced with uncertainty
