Event Notification Report for April 20, 2026

AGREEMENT STATE REPORT - DAMAGED GAUGE

The following information was provided by the Alabama Office of Radiation Control via email:

"On April 7, 2026, at approximately 1230 CST, the Alabama Office of Radiation Control received a call from the radiation safety officer (RSO) for Building & Earth Sciences, LLC. The RSO reported that a Troxler 3440 portable moisture/density gauge with serial number 22948 containing 8 mCi of Cs-137 (serial number 75-4750) and 40 mCi of Am/Be-241 (serial number 47-18131) was struck by the edge of an excavator's track at a temporary jobsite located in Fultondale, Alabama. The RSO stated that after the incident, surveys were performed of the portable gauge in its transport container (did not exceed transportation index), the area where the incident occurred (no measurable readings), and the excavator tracks (no measurable readings). A leak test was also performed onsite prior to the gauge being transported back to Building & Earth Sciences, LLC's office for storage in their vault until it can be returned to Troxler for disposal. The RSO stated that the incident occurred because the technician turned his back for a moment while working near the excavator."

Alabama Incident Number: 26-04

AGREEMENT STATE REPORT - LEAKING SOURCE

The following information was provided by the Alabama Office of Radiation Control via email:

"On April 10, 2026, the radiation safety officer (RSO) provided a written notification for a leaking source to the [Alabama Office of Radiation Control] License and Registration Branch supervisor. Specifically, [the source is] an Eckert & Ziegler, Isotope Products sealed source, source number 1145-50-12, with a reference date of March 1, 2006, and a reference activity of 197 microcuries [of Cs-137]. The licensee's representative indicated in the notification that, while the initial wipe test was close to exceeding the limits, subsequent wipe tests exceeded them. The licensee's representative further stated that a visible crack was present in the e-vial's plastic. The licensee's representative removed the e-vial from use, placed it into a sealed plastic bag, placed the sealed plastic bag into a labeled lead pig, and placed the lead pig in a locked storage room in the radiation safety office."

Alabama Incident Number: 26-05

TECHNICAL SPECIFICATION REQUIRED SHUTDOWN

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

"On April 16, 2026, at 2102 CDT, Browns Ferry Unit 1 was operating at 100 percent reactor power when a plant shutdown was initiated due to technical specification (TS) requirements. At 1530 CDT on April 16, 2026, while investigating a leak in the reactor steam vault, a reactor coolant system (RCS) pressure boundary leak was identified. TS limiting condition of operation 3.4.4 condition 'A' was entered with a required action to isolate the affected component, pipe, or vessel from the reactor coolant water by use of a closed manual valve, closed and deactivated automatic valve, blind flange, or check valve within 4 hours. Due to the leak being unisolable, TS 3.4.4 condition 'D' was entered with required action to be in mode 3 within 12 hours and mode 4 within 36 hours.

"This event requires an 8-hour report in accordance with (IAW) 50.72(b)(3)(ii)(A) Degraded Condition for the flaw in the RCS boundary, and a 4-hour report IAW 50.72(b)(2)(i), 'The initiation of any nuclear plant shutdown required by the plant's technical specifications.'

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

FITNESS FOR DUTY

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

"At 1008 [CDT] on 4/17/26, it was determined that a licensed operator tested positive in accordance with the fitness-for-duty (FFD) testing program. The individual's authorization for site access has been terminated.

"The NRC Resident Inspector has been notified."