Event Notification Report for November 13, 2020
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
11/12/2020 - 11/13/2020
EVENT NUMBERS
54996
54996
Power Reactor
Event Number: 54996
Facility: Limerick
Region: 1 State: PA
Unit: [1] [] []
RX Type: [1] GE-4,[2] GE-4
NRC Notified By: Tim Gallacher
HQ OPS Officer: Jeffrey Whited
Region: 1 State: PA
Unit: [1] [] []
RX Type: [1] GE-4,[2] GE-4
NRC Notified By: Tim Gallacher
HQ OPS Officer: Jeffrey Whited
Notification Date: 11/13/2020
Notification Time: 05:32 [ET]
Event Date: 11/13/2020
Event Time: 02:45 [EST]
Last Update Date: 11/13/2020
Notification Time: 05:32 [ET]
Event Date: 11/13/2020
Event Time: 02:45 [EST]
Last Update Date: 11/13/2020
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS Actuation - Critical
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS Actuation - Critical
Person (Organization):
ERIN CARFANG (R1DO)
ERIN CARFANG (R1DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | A/R | Y | 100 | Power Operation | 0 | Hot Shutdown |
AUTOMATIC REACTOR SCRAM DUE TO HIGH REACTOR PRESSURE SIGNAL
"At 0245 EST on November 13, 2020, the Limerick Unit 1 reactor automatically scrammed on a valid Reactor High Pressure signal (1096psig). The Reactor High Pressure signal was caused by the closure of the 1B Inboard Main Steam Isolation Valve (MSIV), causing reactor pressure to rise, exceeding the Reactor Protection System (RPS) setpoint of 1096psig.
"The shutdown was normal and the plant is stable in Hot Shutdown with normal pressure control via the Main Steam Bypass Valves to the Main Condenser and normal level control using the Feedwater System.
"The closure of the 1B Inboard MSIV appears to have been caused by a loss of Primary Containment Instrument Gas (PCIG) pneumatic supply to the valve."
The licensee notified the NRC Resident Inspector, and will be notifying Berks, Chester, and Montgomery Counties, as well as the Pennsylvania Emergency Management Agency.
"At 0245 EST on November 13, 2020, the Limerick Unit 1 reactor automatically scrammed on a valid Reactor High Pressure signal (1096psig). The Reactor High Pressure signal was caused by the closure of the 1B Inboard Main Steam Isolation Valve (MSIV), causing reactor pressure to rise, exceeding the Reactor Protection System (RPS) setpoint of 1096psig.
"The shutdown was normal and the plant is stable in Hot Shutdown with normal pressure control via the Main Steam Bypass Valves to the Main Condenser and normal level control using the Feedwater System.
"The closure of the 1B Inboard MSIV appears to have been caused by a loss of Primary Containment Instrument Gas (PCIG) pneumatic supply to the valve."
The licensee notified the NRC Resident Inspector, and will be notifying Berks, Chester, and Montgomery Counties, as well as the Pennsylvania Emergency Management Agency.