The inspectors identified a finding of very low safety significance with an associated Non-Cited Violation of
10 CFR Part 50 Appendix B, Criterion III, Design Control, for failing to maintain safety-related cables in an environment for which they were designed. Specifically, frequently submerged safety-related cables in manholes MH1PA, MH1PB, MH1PC, and MH1PD were designed to be moisture resistant and not completely submerged in water. For corrective actions, the frequency for conducting preventive maintenance to inspect the manholes for water and pump out the water, as needed, was reduced from monthly to weekly for manhole MH1PA and to biweekly for manholes MH1PB, MH1PC, and MH1PD. In addition, engineering personnel were evaluating permanent solutions to prevent the manholes from filling with water, which would eliminate the need for manual pumping. This finding was entered into the licensees corrective action program as
AR 00859564. This finding affected the
Initiating Events cornerstone and was more than minor because the issue could become a more significant safety concern if left uncorrected. Specifically, allowing safety-related cables to be repeatedly submerged in water in underground manholes could degrade the cable insulation and result in cable failure. The finding was of very low safety significance because the finding does not contribute to both the likelihood of a
reactor trip and the likelihood that mitigating equipment or functions would be lost. This finding was associated with a cross-cutting aspect in the area of problem identification and resolution in corrective action program corrective actions (P.1.(d))
