The following violation of very low safety significance (Green) was identified by the licensee and is a violation of NRC requirements which met the criteria of the
NRC Enforcement Policy for being dispositioned as an
NCV.
10 CFR 50 Appendix B, Criterion XVI, Corrective Action, states, in part, that measures shall be established to assure that
conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and non-conformances are promptly identified and corrected. Contrary to the above,
conditions adverse to quality related to the main control room chilled water circulating pumps A-A and B-B and shutdown board room chilled water circulating pumps A-A and B-B were not corrected which resulted in the chillers being
inoperable and reportable. The inspectors performed a Phase 1 evaluation per
IMC 0609, Attachment 4, and determined that the finding was potentially risk significant because it involved the degradation of equipment specifically designed to mitigate a seismic, flooding, or severe weather initiating event (e.g., seismic
snubbers, flooding barriers, tornado doors). Consequently, a Phase 3 analysis was performed by a Senior Reactor Analyst. The analyst estimated the frequency of the
PMP event, adjusted for the time of year when room cooling would be necessary and multiplied by a conservative value for ACCDP (0.1) representing the likelihood for core damage due to alternate shutdown from outside the control room. The analyst determined that the risk significance of the issue was very low (i.e., ACDF < 1.0E-6). Because this finding is of very low safety significance (Green) and has been entered into the corrective action program as PER 641937, this violation is being treated as an
NCV, consistent with the
NRC Enforcement Policy.
