The team identified a non-cited violation of McGuire Unit 1 and 2 Operating License Condition 2.C.4 for the licensees failure to evaluate potential blockage of the Turbine Driven
Auxiliary Feedwater (TDCA) pump
lube oil cooler when pump suction is aligned to the circulating water (RC) system. Specifically, during certain fire events causing loss of plant control, the team identified that if the RC system piping was aligned to the suction of the TDCA pump as in accordance with the licensing basis, it could result in blockage of cooling water flow for the TDCA pump
lube oil cooler. Immediate actions by the licensee included performing a functional assessment and evaluating potential long term corrective actions. The licensee entered this issue in their corrective action program as
PIP M-12-2174. The performance deficiency was determined to be more than minor because it was similar to
IMC 0612 Appendix E question 3j in that, there was reasonable doubt as to the operability of the
auxiliary feedwater system when suction was supplied from RC system. In addition, the finding was associated with the design control attribute of the
Mitigating Systems Cornerstone and affected the cornerstone objective of ensuring the availability, reliability, and capability of systems that respond to
initiating events to prevent undesirable consequences. The finding was evaluated using
IMC 0609, Attachment 4, Phase 1, and
IMC 0609 Appendix F, Fire Protection
Significance Determination Process , Attachment 1, Phase 1 and determined to be of low safety significance because it only affected the ability to reach and maintain cold shutdown. The team determined that no cross cutting aspect was applicable to this performance deficiency because this finding was not indicative of current licensee performance.
