Green . A finding of very low safety significance and an associated
NCV of 10 CFR 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, was self -revealed for the licensees failure to ensure that activities affecting quality were prescribed in a manner appropriate to the circumstances for the Unit 2, Division 3 , diesel generator (
DG) system . Specifically, the licensees processes for the control and administration of preventive maintenance (ER
AA 200/WC
AA 120) failed to ensure that safety -related valve, 2E22 F319, the 2B
DG cooling water strainer backwash valve, was replaced or refurbished at a frequency that would prevent corrosion- related stem -to-disc separation. The licensee entered this issue int o the ir
CAP as
AR 1122320. Corrective actions planned and completed included replacement of the 2E22 F319 valve with a stainless steel design and performing an apparent cause evaluation of the degraded condition. The performance deficiency was more than minor because it was associated with the
Mitigating Systems Cornerstone attribute of equipment performance and adversely affected the cornerstone objective of ensuring the availability, reliability, and capability of systems that respond to
initiating events to prevent undesirable consequences (i.e., core damage) . Specifically, the failure to perform preventive maintenance on the 2E22 F319 valve resulted in a degraded condition which adversely affected the reliability of the high pressure
core spray system to respond to an initiating event. The inspectors evaluated the finding using the
significance determination process in accordance with
IMC 0609, Appendix A, The
Significance Determination Process for Findings At -Power, Exhibit 2, dated June 19, 2012. The inspectors reviewed the
Mitigating Systems screening questions in Exhibit 2 and answered No to question A.1, If the finding is deficiency affecting the design or qualification of a mitigating
SSC [structure, system, or component] , does the
SSC maintain its operability or functionality. The inspectors answered Yes to question A.2, Does the finding represent a loss of system and/or function; therefore, a detailed risk evaluation was required. The detailed risk evaluation determined that the finding screened as having very low safety significance (Green). This finding had a cross -cutting aspect in the area of Problem Identification and Resolution, because t he organization failed to take effective corrective actions to address issues in a timely manner commensurate with their safety significance (P .3).
