Event Notification Report for January 07, 2026

EN Revision Imported Date: 1/7/2026

EN Revision Text: CONTROL ROOM EMERGENCY VENTILATION SYSTEM INOPERABLE

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

"At 0911 EST, on 11/17/2025, it was discovered that both trains of the control room emergency ventilation system were simultaneously inoperable due to an unauthorized door breach of a door in the control room envelope; therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v)(D). At 0913 EST, the door was closed, and both trains of the control room emergency ventilation system were restored to operable.

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

* * * RETRACTION ON 1/6/2026 AT 1340 EST FROM ALEX BLAINE TO ERNEST WEST * * *

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

"Based on further engineering analysis, sufficient time margin existed to allow the control room emergency ventilation system (CREVS) to successfully mitigate the impacts of an accident. The duration of the breach was less than the analyzed time for accident conditions to impact the control room envelope. Operations has revised and retracted the technical specification entries after evaluating that CREVS remained operable during the breach event. Therefore, the NRC non-emergency 10 CFR 50.72(b)(3)(v)(D) report was not required and NRC event notification 58042 is retracted. No licensee event report under 10 CFR 50.73(a)(2)(v)(D) is required to be submitted. The NRC Resident Inspector has been notified."

Notified R2DO (Nielsen)

AGREEMENT STATE REPORT - STUCK SHUTTER

The following is a summary of information provided by the New Mexico Environment Department via email:

On December 29, 2025, at approximately 1030 MST, while attempting to free a shutter that had difficulty moving during an inspection, the shutter mechanism broke. The shutter is currently stuck open in its normal operating configuration on a pipeline. The source is a Berthold cesium-137, 30 mCi, model P-2623-100 in a Berthold model LB7440 holder. Radiation Technology, Inc., has been contacted for radiation support. They are scheduled to come to the site in January and plan on either replacing or fixing the shutter mechanism at that time. This repair or replacement should be completed no later than January 31, 2026.

AGREEMENT STATE REPORT - STUCK-OPEN GAUGE SHUTTER

The following information was provided by the South Carolina Department of Environmental Services (the Department) via phone and email:

"The licensee informed the Department on December 31, 2025, that a fixed gauging device was disabled or failed to function as designed. The licensee reported that a Berthold model LB 7400-series fixed gauging device (serial number KW507), containing a 20 mCi Cs-137 sealed source, had a shutter stuck in the open position and that the shutter handle had broken off. The licensee reported that the device is attached to a process vessel and indicated that access has been restricted. The licensee also reported that dose rate survey results of the gauging device were at background.

"The licensee did not report any overexposures or ongoing health/safety concerns.

"A Department inspector will be dispatched to the facility. This event is still under investigation by the Department."

INVALID SPECIFIED SYSTEM ACTUATION

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

"This report is being made in accordance with 10 CFR 50.73(a)(2)(iv)(A), using the telephone option in 10 CFR 50.73(a)(1) in lieu of a written licensee event report, concerning an event in which Callaway experienced an automatic actuation of the auxiliary feedwater (AFW) system in response to invalid AFW actuation signals. The reactor protection system was not involved. A low suction pressure signal was also received which aligned the AFW pumps to essential service water. An unknown amount of water from the ultimate heat sink entered the steam generators, necessitating a plant shutdown after secondary water chemistry program action levels were exceeded. This AFW actuation was complete and the AFW system started and functioned successfully in accordance with the initiating actuation signals. This actuation occurred at 0748 CST on November 12, 2025, and was reported (and later retracted) as event notification 58035.

"The most probable cause of the actuations was the intermittent failure of a 15V DC logic power supply within engineered safety features actuation system logic cabinet SA036D. The power supply was replaced."