The following violation of very low safety significance (Green) was identified by Exelon and is a violation of NRC requirements, which meets the criteria of the
NRC Enforcement Policy for being dispositioned as a
NCV.
10 CFR 50.65(a)(4) states, in part, that before performing maintenance activities (including but not limited to surveillance, post-maintenance testing, and corrective and preventive maintenance), the licensee shall assess and manage the increase in risk that may result from the proposed maintenance activities. The scope of the assessment may be limited to structures, systems, and components that a risk-informed evaluation process has shown to be significant to public health and safety. Contrary to the above, on March 28, 2011, and April 16, 2015, before performing maintenance activities on the electric bay unit coolers, as discussed in Section 4OA2.4, Exelon did not assess and manage the increase in risk that resulted from the maintenance activities. This issue was documented in Condition Report [[::JAF-2016-0838|JAF-2016-0838]]. In accordance with
IMC 0609.04, Initial Characterization of Findings, and
IMC 0609 Appendix K, Flowchart 2, Assessment of
RMAs. The inspectors determined that the violation was of very low safety significance (Green) because the incremental core damage probability was less than
1E-5, with three risk management actions taken during the maintenance activities.
