The inspectors identified a self-revealing
NCV of
Technical Specification 5.4.1.a when control room operators closed the inlet and outlet
Residual Heat Removal (
RHR) system isolation valves while conducting a plant heat-up with the A
reactor coolant system loop
inoperable. This was contrary to procedural requirements which require operators to verify that two
reactor coolant system loops are
operable and at least one is operating prior to isolating the
RHR system. Several minutes after isolating the
RHR system, the control room operators recognized they were not complying with the procedure, and restored power to the
RHR isolation valves. The time that the
RHR system was isolated from the
reactor coolant system was 15 minutes. This finding was determined to be of very low safety significance (Green) using Phase 1, Appendix G, Attachment 1, Checklist 4 of
IMC 0609. This finding was of very low safety significance because the finding did not increase the likelihood of a loss of
RCS inventory, degrade the ability of Ginna to terminate a leak path or add
RCS inventory when needed, nor degrade the ability to recover
RHR. This finding has a crosscutting aspect in the area of human performance because operators did not adhere to the procedural requirements prior to removing the
RHR system from service (
H.4.b per
IMC 0305)
