Skip to main content

Event Notification Report for January 04, 2025

U.S. Nuclear Regulatory Commission
Operations Center

EVENT REPORTS FOR
01/03/2025 - 01/04/2025

EVENT NUMBERS
57485
Power Reactor
Event Number: 57485
Facility: Watts Bar
Region: 2     State: TN
Unit: [1] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: Sean Lorson
HQ OPS Officer: Adam Koziol
Notification Date: 01/04/2025
Notification Time: 14:45 [ET]
Event Date: 01/04/2025
Event Time: 08:55 [EST]
Last Update Date: 01/04/2025
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(3)(v)(D) - Accident Mitigation
Person (Organization):
Franke, Mark (R2DO)
Power Reactor Unit Info
Unit SCRAM Code RX Crit Initial PWR Initial RX Mode Current PWR Current RX Mode
1 N Y 100 Power Operation 100 Power Operation
2 N Y 100 Power Operation 100 Power Operation
Event Text
INOPERABILITY OF BOTH TRAINS OF THE CONTROL ROOM EMERGENCY AIR TEMPERATURE CONTROL SYSTEM (CREATCS)

The following information was provided by the licensee via phone and email:

"At 0855 EST on 01/04/2025, it was discovered that both trains of the CREATCS were simultaneously inoperable; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v)(D).

"At 1408 on 01/04/2025, the 'A' main control room (MCR) chiller was restored to operable following corrective maintenance, and technical specification (TS) limiting condition for operation (LCO) 3.0.3 was exited. The 'B' MCR chiller remains inoperable due to a component outage.

"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The 'A' MCR chiller tripped due to low oil level. LCO 3.0.3 was entered in accordance with TS 3.7.11.