A self-revealing Apparent Violation (
AV) of
Technical Specification 5.4.1 was identified for the licensees failure to properly implement procedure 2-OI-99,
Reactor Protection System. Specifically, during restoration of 2B
Reactor Protection System (
RPS) 480 volt power, the
RPS motor generator set tie to battery BD 2 Breaker on the 2A
RPS bus motor generator set was incorrectly opened. The licensee took immediate actions to respond to the resultant Unit 2
scram and placed the unit in a shutdown condition. Subsequent corrective actions included operator training and procedure revisions. The licensee entered this issue into their corrective action program as Problem Evaluation Report (PER) 660862. This finding was determined to be more than minor because it was associated with the
Initiating Events cornerstone attribute of the human performance area and adversely affected the cornerstone objective to limit the likelihood of those events that upset plant stability and challenge critical safety functions during at-power operations. Specifically, the failure to properly implement procedure 2-OI-99 caused a Unit 2 reactor
scram and
main steam isolation valves (
MSIV) closure. Because the finding could not be screened as very low safety significance (Green), nor its safety significance determined prior to issuing the inspection report, it is being characterized as To Be Determined (
TBD). The cause of this finding was directly related to the cross-cutting aspect of Human Error Prevention in the Work Practices component of the Human Performance area, because the lack of adequate self-check, peer checking, and pre-job briefing resulted in the operator opening the incorrect breaker.