|AUTOMATIC REACTOR SCRAM DUE TO MAIN TURBINE TRIP
"At 1800 EST, on February 12, 2020, with Unit 1 in Mode 1 at 100 percent power, the reactor automatically tripped due to a turbine trip. The trip was not complex, with all systems responding normally post trip. Because of the reactor trip, the Auxiliary Feedwater (AFW) System actuated as expected due to on ATWS Mitigation System Actuation Circuitry (AMSAC) signal. The AFW pumps started as designed when the valid system actuation was received.
"Operations responded and stabilized the plant. Decay heat is being removed by discharging steam to the main condenser using the condenser steam dump valves.
"Due to the Reactor Protection System (RPS) actuation while critical, this event is being reported as an 4-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B). This event is also being reported as an 8-hour non-emergency notification per 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the AFW system.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified.
"The site remains in a normal electrical lineup."
The cause of the turbine trip is under investigation.