Event Notification Report for May 29, 2025

AGREEMENT STATE REPORT - MEDICAL EVENT

The following information is a summary provided by the Florida Bureau of Radiation Control (BRC) via email:

The radiation safety officer (RSO) called the BRC to report a medical event involving Y-90 microspheres. The RSO stated that on 5/16/2025 it was planned for the patient to receive two administrations of 22 mCi microspheres. It was discovered on 5/20/2025 at 1730 EDT that the patient received only an administration of 3.54 mCi for the first treatment and 3.35 mCi for the second treatment. The attending physician and patient have both been notified. A report from the RSO will follow.

A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.

AGREEMENT STATE REPORT - LOST SOURCE

The following information was provided by the Florida Bureau of Radiation Control (BRC) via email:

"The radiation safety officer (RSO) called the BRC to report a lost Ge-68 pin source from their PET scanner. It was discovered missing about a week ago. The RSO said the source had a reference date of April 1, 2021, with an initial activity of 1.49 mCi. Apparently, the previous consultant tried to send it back to Eckert and Zeigler in 2021, but it was returned twice from the common carrier due to not being packaged properly. Eckert and Zeigler apparently never received the source. The RSO has copies of the paperwork from the common carrier, but the dates do not line up. The BRC Miami inspection office will follow up with an investigation."

Florida Incident Number: FL25-049.

INVALID CONTAINMENT ISOLATION

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

"This 60-day telephone notification is being made per the reporting requirements specified by 10 CFR 50.73(a)(2)(iv)(A) and 10 CFR 50.73(a)(1) to describe an invalid actuation of a general containment isolation signal affecting more than one system [for Browns Ferry Unit 2].

"On March 28, 2025, operations personnel were performing post-maintenance testing of 2-HS-64-33 [hand switch], which operates 2-FSV-64-33, the suppression chamber exhaust outboard isolation valve. When the hand switch was taken to 'open' multiple annunciators were received, including 9-5B window 34, 'Fuse Failure'. Light indications above the hand switch were not lit. This condition resulted in a 'B'-side partial group 6 isolation. All systems responded as expected.

"Plant conditions which initiate primary containment isolation system (PCIS) group 6 actuations are reactor vessel low water level (level 3), high drywell pressure, or reactor building ventilation exhaust high radiation (reactor zone or refuel zone).

"At the time of the event, these conditions did not exist; therefore, the actuation of the PCIS was invalid and there were no safety consequences or impact to the health and safety of the public as a result of this event.

"Upon investigation a fuse was found to be cleared, which was the cause of the isolation. The fuse was replaced, the condition was cleared, and all systems were realigned as necessary.

"This event was entered into the corrective action program as condition report 2002404.

"The NRC Resident Inspector has been notified of this event."

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
Units 1 and 3 were not affected.

MANUAL REACTOR TRIP AND AUXILIARY FEEDWATER ACTUATION

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

"At 1253 EDT, on May 28, 2025, with Unit 1 in mode 1 at 100 percent power, the reactor was manually tripped due to a loss of main feedwater pump `A'. The trip was not complex, with all systems responding normally post-trip.

"Operations responded and stabilized the plant. Decay heat is being removed by discharging steam through the steam dumps to the main condenser. Units 2, 3, and 4 are not affected. An automatic actuation of auxiliary feedwater (AFW) also occurred. The AFW auto-start is an expected response from the reactor trip.

"Due to the reactor protection system actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B). This event is also being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the auxiliary feedwater system.

"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:

All control rods inserted on the trip. A main feedwater pump lube oil evolution was in progress at the time of the trip.