MANUAL REACTOR SCRAM
"At 1255 Eastern Daylight Time (EDT) on March 22, 2020, with Unit 1 in Mode 2, stabilized at 2 percent power, coming out of a refueling outage, all 4 main turbine Bypass Valves (BPVs) opened unexpectedly. As a result, the main control room inserted a manual reactor scram. All control rods inserted as expected during the scram.
"In accordance with plant procedures, the main control room closed all Main Steam Line Isolation Valves (MSIVs) to arrest the cooldown resulting from BPVs remaining open. The condensate system remained aligned for injection and pressure control was initially via main steam line drains. RHR [residual heat removal] shutdown cooling was placed in operation for decay heat removal and pressure control once the MSIVs were closed.
"All systems responded as designed, with the exception of the BPVs.
"Due to the Reactor Protection System actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B).
"There was no impact on the health and safety of the public or plant personnel.
"The NRC Resident Inspector has been notified."
There was no impact to Unit 2. |