The inspectors identified a
NCV of
VCS TS 3.8.1.1.b.4 caused by the failure to conduct proper post modification testing after implementation of modification ECR-50555. This testing failed to identify that the voltage regulator settings and the reverse power relay portion of the modification were improperly implemented. Further, it impacted the reliability and availability of the Parr alternate
AC supply to
VCSs safety buses. The licensee initiated procedures for setting the voltage regulators and bypassed the reverse power relay. These issues were entered into the corrective action program.
LER 05000395/2008004 was also submitted on October 10, 2008 by the licensee associated with the TS violation. This finding is more than minor because exceeding a Technical Specification Limiting Condition of Operation affects the
Mitigating Systems Cornerstone objective of ensuring the availability, reliability, and operability of the
EDGs to perform their intended safety function during a design basis event, and the cornerstone attribute of Equipment Performance:, i.e. availability. Following a Phase 3 analysis under the
Significance Determination Process (
SDP) the finding was determined to be of very low safety significance. The cause of this finding was related to the cross-cutting area of problem identification and resolution, specifically with respect to corrective action, because the licensee did not thoroughly evaluate the anomalous operation of the Parr generator voltage regulators and the reverse power relay in November 2006, such that the resolution adequately addressed causes and extent of condition. (
P.1.c) (Section 1R21.2.19
