The inspectors identified a finding of very low safety significance and an associated
NCV of
10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, for the failure of two contractor welders to adhere to welding procedures for the
weld overlay (
WOL) repairs on two pressurizer
safety relief valve (
SRV) nozzles. Specifically, both welders failed to use calculated relative travel speed settings as required by procedure in order to ensure that correct heat input values (an essential variable) were maintained. The licensee entered the issue into their corrective action program and suspended welding activities on the two
SRVs until it was determined that the travel speeds used resulted in a heat input that was bounded by the procedure as qualified. This finding is greater than minor because if left uncorrected it would have become a more significant safety concern in that the failure to control heat input could have reduced the impact toughness of the
WOL such that it would be susceptible to brittle fracture. The finding is of very low safety significance because calculations determined that the resulting heat inputs were bound by the welding procedure specifications (WPS) parameters. As a result, assuming worst case degradation, it is unlikely that there would be
reactor coolant system leakage or the loss of safety function of any mitigating system. The cause of the finding is related to the cross-cutting aspect of Human Performance, Work Practices, (Item H.4.(c)) because licensee personnel failed to ensure supervisory and management oversight activities of their contractors such that nuclear safety was ensured. (Section 1R08
