Event Notification Report for August 08, 2020
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
08/07/2020 - 08/08/2020
EVENT NUMBERS
54824
54824
Power Reactor
Event Number: 54824
Facility: Grand Gulf
Region: 4 State: MS
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: Gabriel Hargrove
HQ OPS Officer: Brian Lin
Region: 4 State: MS
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: Gabriel Hargrove
HQ OPS Officer: Brian Lin
Notification Date: 08/08/2020
Notification Time: 05:34 [ET]
Event Date: 08/08/2020
Event Time: 01:27 [CDT]
Last Update Date: 08/08/2020
Notification Time: 05:34 [ET]
Event Date: 08/08/2020
Event Time: 01:27 [CDT]
Last Update Date: 08/08/2020
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS Actuation - Critical 50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS Actuation - Critical 50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
Person (Organization):
GREG PICK (R4DO)
GREG PICK (R4DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | M/R | Y | 86 | Power Operation | 0 | Hot Shutdown |
REACTOR SCRAM DUE TO A TURBINE HIGH PRESSURE CONTROL VALVE MALFUNCTION
On August 8, 2020, at 0127 CDT, Grand Gulf Nuclear Station was manually shut down due to a turbine high pressure control valve malfunction. Reactor pressure is being controlled with bypass control valves to the main condenser. Reactor level is being maintained with condensate and feedwater through startup level control. The plant is stable in MODE 3 and proceeding to cold shutdown. The cause of the 'D' high pressure control valve malfunction is under investigation at this time.
All rods fully inserted and there were no complications. All systems responded as designed.
This event is being reported under 10 CFR 50.72(b)(2)(iv)(B), as any event or condition that results in actuation of the Reactor Protection System (RPS) when the reactor is critical.
Additionally, at 0159 CDT, with all rods fully inserted and after the 0127 CDT manual reactor Scram, an automatic valid RPS actuation signal was received.
This event is also being reported under 10 CFR 50.72(b)(3)(iv)(A), as an event or condition that results in a valid actuation of any of the systems listed in 10 CFR 50.72(b)(3)(iv)(B).
On August 8, 2020, at 0127 CDT, Grand Gulf Nuclear Station was manually shut down due to a turbine high pressure control valve malfunction. Reactor pressure is being controlled with bypass control valves to the main condenser. Reactor level is being maintained with condensate and feedwater through startup level control. The plant is stable in MODE 3 and proceeding to cold shutdown. The cause of the 'D' high pressure control valve malfunction is under investigation at this time.
All rods fully inserted and there were no complications. All systems responded as designed.
This event is being reported under 10 CFR 50.72(b)(2)(iv)(B), as any event or condition that results in actuation of the Reactor Protection System (RPS) when the reactor is critical.
Additionally, at 0159 CDT, with all rods fully inserted and after the 0127 CDT manual reactor Scram, an automatic valid RPS actuation signal was received.
This event is also being reported under 10 CFR 50.72(b)(3)(iv)(A), as an event or condition that results in a valid actuation of any of the systems listed in 10 CFR 50.72(b)(3)(iv)(B).