A self-revealing
NCV of
TS 5.4.1, Procedures, was identified in that operators failed to properly align and check the position of the B
reactor coolant system (
RCS) loop bypass valve [2RCS*45]. as required by procedure. This deficiency caused an incorrect lineup of the required vent path and resulted in the over-pressurization of the isolated B
RCS loop while filling. The estimated pressure exceeded the pressurel temperature limit for an isolated
RCS loop on November 11. The inspectors determined that the finding was not similar to the examples for minor deficiencies contained in
IMC 0612, Appendix E, Examples of Minor Issues, The finding was more than minor because if left uncorrected could have the. potential to
lead to a more significant safety concern. Traditional enforcement does not apply because the issue did not have an actual safety consequence or the potential for ill)pacting NRCs regUlatory function, and was not the result of any willful violation of NRC requirements. The inspectors performed a Phase 1
SOP evaluation in accordance with fMC 0609, Appendix G, Attachment 1, CHECKLIST 4
PWR Refueling Operation:
RCS level> 23
OR PWR Shutdown Operation with Time to Boil>
2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> And Inventory in the Pressurizer. Because the loop was isolated from the reactor vessel and pressurizer, the required
reactor coolant inventory and the
decay heat removal system were not affected. There were no conditions indicating a loss of control as listed in Appendix G, Table 1 Losses of Control. Therefore. a Phase 2 quantitative assessment was not required and the issue screened to Green (very low safety significance). Because this finding is of very low safety significance and has been entered into
FENOCs corrective action program, the violation is being treated as a non-cited violation. The cause of this find(ng is related to the cross~cutting area of human performance, work practices, in that
FENOCs failed to follow station procedures resulting in an overpressurization of the isolated B
RCS loop. [H.4.(b)].