10 CFR 50, Appendix B, Criterion XI, "Test Control," requires, in part, that a test program be established to assure that all testing required to demonstrate that
SSCs will perform satisfactorily in service is performed in accordance with written test procedures. Contrary to the above, prior to October 2014, Exelon did not perform adequate periodic and independent testing to demonstrate that the relays that provide permissives for
emergency diesel generator breaker closing to the emergency buses would perform satisfactorily in the event of a postulated single failure during a design basis event. Exelon entered the issue into their
CAP as
AR 02344861, and tested and replaced the relays in question. The inspectors determined the finding was of very low safety significance (Green) in accordance with
IMC 0609, Appendix A, The
Significance Determination Process (
SDP) for Findings At-Power, Exhibit 2, Mitigating System Screening Questions, issued June 19, 2012, since the finding was not a deficiency affecting the design or qualification of a mitigating
SSC, did not represent a loss of system and/or function, and did not represent an actual loss of function of at least a single train.
