Event Notification Report for June 22, 2025
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
06/21/2025 - 06/22/2025
EVENT NUMBERS
57774
57774
Power Reactor
Event Number: 57774
Facility: North Anna
Region: 2 State: VA
Unit: [1] [] []
RX Type: [1] W-3-LP,[2] W-3-LP,[3] M-4-LP
NRC Notified By: Dennis Bried
HQ OPS Officer: Troy Johnson
Region: 2 State: VA
Unit: [1] [] []
RX Type: [1] W-3-LP,[2] W-3-LP,[3] M-4-LP
NRC Notified By: Dennis Bried
HQ OPS Officer: Troy Johnson
Notification Date: 06/23/2025
Notification Time: 01:40 [ET]
Event Date: 06/22/2025
Event Time: 22:04 [EDT]
Last Update Date: 06/23/2025
Notification Time: 01:40 [ET]
Event Date: 06/22/2025
Event Time: 22:04 [EDT]
Last Update Date: 06/23/2025
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
10 CFR Section:
50.72(b)(3)(iv)(A) - Valid Specif Sys Actuation
Person (Organization):
Blamey, Alan (R2DO)
Blamey, Alan (R2DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 100 | Power Operation |
VALID EMERGENCY DIESEL GENERATOR START
The following information was provided by the licensee via phone and email:
"At 2204 EDT on 6/22/2025, with unit 1 and unit 2 operating at 100 percent power, the 'A' reserve station service transformer (RSST) was lost which resulted in the loss of power to the '1J' emergency bus. As a result of the power loss, the '1J' emergency diesel generator (EDG) automatically started as designed and restored power to the '1J' emergency bus. During the event, the unit 1 'A' charging pump (1-CH-P-1A) automatically started as designed due to the loss of power event. Security footage reported a bright white flash associated with the 'A' RSST at the time of the event.
"The valid actuation of these ESF components due to loss of electrical power is reportable per 10 CFR 50.72(b)(3)(iv)(A).
"The '1J' emergency bus off-site power source was restored to service via an alternate source and the '1J' EDG was secured and returned to automatic. Restoration of offsite power to operable is complete. 1-CH-P-1A was secured and returned to automatic. Both units are currently stable, and an investigation is underway to determine the cause of the loss of the 'A' RSST."
Unit 2 was unaffected. The NRC resident inspector was notified.
The following information was provided by the licensee via phone and email:
"At 2204 EDT on 6/22/2025, with unit 1 and unit 2 operating at 100 percent power, the 'A' reserve station service transformer (RSST) was lost which resulted in the loss of power to the '1J' emergency bus. As a result of the power loss, the '1J' emergency diesel generator (EDG) automatically started as designed and restored power to the '1J' emergency bus. During the event, the unit 1 'A' charging pump (1-CH-P-1A) automatically started as designed due to the loss of power event. Security footage reported a bright white flash associated with the 'A' RSST at the time of the event.
"The valid actuation of these ESF components due to loss of electrical power is reportable per 10 CFR 50.72(b)(3)(iv)(A).
"The '1J' emergency bus off-site power source was restored to service via an alternate source and the '1J' EDG was secured and returned to automatic. Restoration of offsite power to operable is complete. 1-CH-P-1A was secured and returned to automatic. Both units are currently stable, and an investigation is underway to determine the cause of the loss of the 'A' RSST."
Unit 2 was unaffected. The NRC resident inspector was notified.