The inspectors identified a finding having very low safety significance and an
NCV of
10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, for the licensees failure to establish inspection procedures that were appropriate for the circumstances. Specifically, the licensees heat exchanger inspection guidance and acceptance criteria could potentially result in the design basis tube plugging limit being exceeded due to the accumulation of macro fouling and as a result the heat exchanger would not be able to meet the design basis heat removal capability. This finding was entered into the licensees corrective action program and a review of the heat exchanger tube plugging analysis identified additional margin to remain within its design basis heat removal capability. The finding was more than minor because if left uncorrected, it would have the potential to
lead to a more significant safety concern. This finding was of very low safety significance (Green) because the licensee was able to demonstrate adequate margin and therefore there was not a design or qualification deficiency, did not represent a loss of system safety function, and did not screen as potentially risk-significant due to a seismic, flooding, or severe weather initiating event. The finding had a cross-cutting aspect in the area of human performance because the licensee did not use conservative assumptions in decision making when developing the inspection guidance and acceptance criteria.
