TS 3/4.5.2,
ECCS Subsystems Tavg > 350 oF states in part that two independent
emergency core cooling system (
ECCS) subsystems shall be
OPERABLE with one
OPERABLE centrifugal charging pump in Modes 1, 2 and 3.
TS 1.18,
OPERABLE OPERABILITY, definition states in part that a subsystem shall be
OPERABLE when all necessary auxiliary equipment that are required for the subsystem are capable of performing their related support functions. Contrary to this, from July 24, 2015, through September 17, 2015, safety-related subsystem chiller, XHX0001A, an auxiliary component supporting the A train charging pump (XPP0043A) was incapable of performing its safety function resulting in the inoperability of XPP0043A for greater than the allowed action times of TS 3/4.5.2. A review of
IMC0609, Appendix A, determined the finding was of very low safety significance (Green) because the finding was not a design deficiency and it did not result in a loss of function. The licensee has documented this problem in their
CAP as CR-15-04395.
