Event Notification Report for June 22, 2025
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
06/21/2025 - 06/22/2025
Power Reactor
Event Number: 57785
Facility: Columbia Generating Station
Region: 4 State: WA
Unit: [2] [] []
RX Type: [2] GE-5
NRC Notified By: Valerie Lagen
HQ OPS Officer: Ian Howard
Region: 4 State: WA
Unit: [2] [] []
RX Type: [2] GE-5
NRC Notified By: Valerie Lagen
HQ OPS Officer: Ian Howard
Notification Date: 06/26/2025
Notification Time: 14:31 [ET]
Event Date: 06/23/2025
Event Time: 08:27 [PDT]
Last Update Date: 06/26/2025
Notification Time: 14:31 [ET]
Event Date: 06/23/2025
Event Time: 08:27 [PDT]
Last Update Date: 06/26/2025
Emergency Class: Non Emergency
10 CFR Section:
21.21(d)(3)(i) - Defects And Noncompliance
10 CFR Section:
21.21(d)(3)(i) - Defects And Noncompliance
Person (Organization):
Bywater, Russell (R4DO)
Part 21/50.55 Reactors, - (EMAIL)
Bywater, Russell (R4DO)
Part 21/50.55 Reactors, - (EMAIL)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | Y | 18 | Power Operation | 0 | Cold Shutdown |
PART 21 REPORT - SOLENOID VALVE DEFECT
The following information was provided by the licensee via phone and email:
"Valcor supplied replacement V70900-45 solenoid valves with substitute EM163-80 EPDM O-ring material (due to the obsolescence of the original E0515-80 material) and certified to the original qualification test report based on Delta Qualification report QRSKC26022-1. These replacement solenoid valves were installed at Columbia Generating Station (CGS) in July 2024 as control rod drive scram discharge volume solenoid drain valves. On September 26, 2024, CGS identified this change in material and the issue was entered into the corrective action program. Columbia's review of the Delta Qualification report identified the justification of the thermal life of the new O-ring compound when used in normally energized valves such as those supplied to CGS was not adequate. This issue was communicated to the NRC with an interim Part 21 notification on November 21, 2024 (ML24326A362).
"Valcor's report of additional testing to attempt to justify the new O-ring material as equal to or better than the original material was submitted to CGS on February 24, 2025. Columbia concluded the justification was inadequate and submitted to a third party for evaluation."
The Senior Resident Inspector has been notified.
The following information was provided by the licensee via phone and email:
"Valcor supplied replacement V70900-45 solenoid valves with substitute EM163-80 EPDM O-ring material (due to the obsolescence of the original E0515-80 material) and certified to the original qualification test report based on Delta Qualification report QRSKC26022-1. These replacement solenoid valves were installed at Columbia Generating Station (CGS) in July 2024 as control rod drive scram discharge volume solenoid drain valves. On September 26, 2024, CGS identified this change in material and the issue was entered into the corrective action program. Columbia's review of the Delta Qualification report identified the justification of the thermal life of the new O-ring compound when used in normally energized valves such as those supplied to CGS was not adequate. This issue was communicated to the NRC with an interim Part 21 notification on November 21, 2024 (ML24326A362).
"Valcor's report of additional testing to attempt to justify the new O-ring material as equal to or better than the original material was submitted to CGS on February 24, 2025. Columbia concluded the justification was inadequate and submitted to a third party for evaluation."
The Senior Resident Inspector has been notified.
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.