Event Notification Report for August 03, 2022
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
08/02/2022 - 08/03/2022
EVENT NUMBERS
56028
56028
Power Reactor
Event Number: 56028
Facility: Farley
Region: 2 State: AL
Unit: [1] [] []
RX Type: [1] W-3-LP,[2] W-3-LP
NRC Notified By: Gene Slone
HQ OPS Officer: Donald Norwood
Region: 2 State: AL
Unit: [1] [] []
RX Type: [1] W-3-LP,[2] W-3-LP
NRC Notified By: Gene Slone
HQ OPS Officer: Donald Norwood
Notification Date: 08/03/2022
Notification Time: 16:25 [ET]
Event Date: 08/03/2022
Event Time: 12:58 [CDT]
Last Update Date: 08/03/2022
Notification Time: 16:25 [ET]
Event Date: 08/03/2022
Event Time: 12:58 [CDT]
Last Update Date: 08/03/2022
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):
Miller, Mark (R2DO)
Miller, Mark (R2DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | A/R | Y | 100 | Power Operation | 0 | Hot Standby |
AUTOMATIC REACTOR TRIP DUE TO LOSS OF POWER TO START-UP TRANSFORMER
The following information was provided by the licensee via email:
"At 1258 CDT on August 3, 2022, with Unit 1 in Mode 1 at 100 percent power, the reactor automatically tripped due to the supply breakers of the 1B startup transformer opening. The fast dead bus transfer for the reactor coolant pumps did not occur during the event. Currently the plant is in Mode 3 on natural circulation.
"Operations responded and stabilized the plant. Decay heat is being removed by steaming with atmospheric relief valves. Unit 2 is not affected.
"An automatic actuation of the 1B diesel occurred because of the power loss to the 1G 4160V bus. Additionally, the actuation of motor driven and turbine driven auxiliary feedwater pumps (AFW) also occurred. AFW auto-start is an expected response from this reactor trip.
"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). This event is also being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the 1B diesel and the auxiliary feedwater system.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
The following information was provided by the licensee via email:
"At 1258 CDT on August 3, 2022, with Unit 1 in Mode 1 at 100 percent power, the reactor automatically tripped due to the supply breakers of the 1B startup transformer opening. The fast dead bus transfer for the reactor coolant pumps did not occur during the event. Currently the plant is in Mode 3 on natural circulation.
"Operations responded and stabilized the plant. Decay heat is being removed by steaming with atmospheric relief valves. Unit 2 is not affected.
"An automatic actuation of the 1B diesel occurred because of the power loss to the 1G 4160V bus. Additionally, the actuation of motor driven and turbine driven auxiliary feedwater pumps (AFW) also occurred. AFW auto-start is an expected response from this reactor trip.
"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). This event is also being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the 1B diesel and the auxiliary feedwater system.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."