A minor, self-revealing violation of
TS 6.8.1.a, Procedures and Programs,was identified for failure to follow procedure AD-OP-ALL-0200, Clearance and Tagging. On April 7, 2018, while the plant was in Mode 3 at 0 percent power, the licensee isolated breaker DP-1A-1 circuit 28 in accordance with clearance OPS-1-18-5015-DEH MODS-0093. Isolating this breaker caused an unexpected auto start signal for both motor driven
auxiliary feedwater (
MDAFW) pumps for a loss of last running main feed pump despite the 1B main
feedwater pump still being in operation. Both
MDAFWs started and operators manually secured the 1B main
feedwater pump to maintain proper
feedwater flow to the
steam generators.
TS 6.8.1.a, requires, in part, that written procedures be implemented covering activities referenced in
Regulatory Guide 1.33, Revision 2, dated February 1978, including safety-related activities carried out during operation of the reactor plant. Procedure AD-OP-ALL-0200, Section 5.5, step 4, states Clearance impacts must be evaluated to ensure that effects on systems and components outside of the boundary are identified and are acceptable, or properly dispositioned. Contrary to this requirement, the licensee did not identify that the isolation of breaker DP-1A-1 circuit 28 would cause the
MDAFWs to auto start in Mode 3 when developing clearance OPS-1-18-5015-DEH MODS-0093. Screening: The violation is minor because the impact to the plant was minimal; the unit was in Mode 3 throughout the event, the reactor remained subcritical, and
feedwater flow to the
steam generators was not lost. Enforcement: Because the performance deficiency is minor, it will not be subject to enforcement action in accordance with the NRCs
Enforcement Policy. The licensee entered this issue into their
CAP as
NCR 02196873. The associated LER is closed.
