Event Notification Report for August 03, 2024
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
08/02/2024 - 08/03/2024
EVENT NUMBERS
57313
57313
Power Reactor
Event Number: 57313
Facility: Sequoyah
Region: 2 State: TN
Unit: [1] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Travis Holcomb
HQ OPS Officer: Robert A. Thompson
Region: 2 State: TN
Unit: [1] [] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Travis Holcomb
HQ OPS Officer: Robert A. Thompson
Notification Date: 09/10/2024
Notification Time: 08:28 [ET]
Event Date: 08/03/2024
Event Time: 08:40 [EDT]
Last Update Date: 09/10/2024
Notification Time: 08:28 [ET]
Event Date: 08/03/2024
Event Time: 08:40 [EDT]
Last Update Date: 09/10/2024
Emergency Class: Non Emergency
10 CFR Section:
50.73(a)(1) - Invalid Specif System Actuation
10 CFR Section:
50.73(a)(1) - Invalid Specif System Actuation
Person (Organization):
Masters, Anthony (R2DO)
Masters, Anthony (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 |
60-DAY NOTIFICATION OF INVALID SPECIFIED SYSTEM ACTUATION
The following information was provided by the licensee via phone and email:
"This 60-day telephone notification is being submitted in accordance with 10 CFR 50.73(a)(1) and 50.73(a)(2)(iv)(A). The event was an invalid actuation of the Unit 1 containment ventilation isolation (CVI) system.
"On August 3, 2024, at 0840 EDT, with Unit 1 at 100 percent power, train 'A' of the CVI system actuated due to an invalid signal from 1-RM-90-130, containment purge air exhaust monitor. 1-RM-90-130 was out of service for maintenance testing at the time of the invalid signal. The cause of the signal was determined to be the result of an installed multimeter timing out, creating a short in the actuation circuitry. The train 'A' CVI signal was a full actuation of that train and the system functioned as designed.
"Prior to and following the CVI alarm, all other radiation monitors were stable at their normal values; therefore, the CVI [actuation] was invalid. Control room operators performed appropriate checks and confirmed that all required automatic actuations occurred as designed. Subsequent completion of the maintenance instruction was successful. This event was entered into the corrective action program as CR 1948103.
"The NRC Resident Inspector was notified."
The following information was provided by the licensee via phone and email:
"This 60-day telephone notification is being submitted in accordance with 10 CFR 50.73(a)(1) and 50.73(a)(2)(iv)(A). The event was an invalid actuation of the Unit 1 containment ventilation isolation (CVI) system.
"On August 3, 2024, at 0840 EDT, with Unit 1 at 100 percent power, train 'A' of the CVI system actuated due to an invalid signal from 1-RM-90-130, containment purge air exhaust monitor. 1-RM-90-130 was out of service for maintenance testing at the time of the invalid signal. The cause of the signal was determined to be the result of an installed multimeter timing out, creating a short in the actuation circuitry. The train 'A' CVI signal was a full actuation of that train and the system functioned as designed.
"Prior to and following the CVI alarm, all other radiation monitors were stable at their normal values; therefore, the CVI [actuation] was invalid. Control room operators performed appropriate checks and confirmed that all required automatic actuations occurred as designed. Subsequent completion of the maintenance instruction was successful. This event was entered into the corrective action program as CR 1948103.
"The NRC Resident Inspector was notified."