Event Notification Report for May 21, 2025

AGREEMENT STATE REPORT - LOST SOURCES
The following report was received by the Illinois Emergency Management Agency (the Agency) via phone and email:

"On May 9, 2025, the Agency was notified that three generally licensed gas chromatographs (GCs) containing 15 mCi of Ni-63, each, could not be located. These are IAEA Category 5 devices that are not likely to be dangerous and cannot cause permanent damage to an individual, even if dispersed. The loss is reportable under 32 Illinois Administrative Code 340.1210 and will be reported to the NRC within 30 days.

"Office of Nuclear Safety - Radioactive Materials emailed 272 general licensees as part of our annual effort to verify accountability of these devices. The laboratory director replied on behalf of Grace Analytical Laboratory stating that the company had a buyout in 2022. The three generally licensed Ni-63 containing GCs on their inventory were not on the buyout purchase and were missing. Two of the GC's are Hewlett-Packard model 19233-1995 with the following serial numbers: L2580 and L1574. The third GC is a Linc Quantum Analytics, model number G23974, serial number U1308.

"Pending appropriate enforcement. This is considered closed."

Illinois Item Number: IL250019

THIS MATERIAL EVENT CONTAINS A 'Less than Cat 3' LEVEL OF RADIOACTIVE MATERIAL

Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf

AGREEMENT STATE- MEDICAL EVENT

The following information was provided by the Illinois Emergency Management Agency (Agency) via phone and email:

"The Agency was contacted the morning of May 13, 2025, by the radiation safety officer (RSO) for Northwestern Memorial Hospital to advise of a medical event involving the administration of Y-90 TheraSpheres that occurred the previous day. Reportedly, the patient received approximately 37.5 percent of the intended dose to their liver. The RSO was unsure at the time of notification if the patient and prescribing physician had been notified. At the time of notification, it was believed that there is no adverse effect to the patient.

"The licensee met the reporting requirement under 32 Illinois Administrative Code 335.1080. Agency inspectors are coordinating a site visit and additional information will be provided as it becomes available."

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.

EN Revision Imported Date: 5/21/2025

EN Revision Text: MANUAL REACTOR SCRAM DUE TO LOSS OF FEEDWATER

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

"At 1045 CDT on May 19, 2025, with Unit 1 at 100 percent power, the reactor was manually tripped on lowering reactor water level caused by a loss of electrical power to the condensate and feedwater pumps. The trip was not complex with all systems responding as expected post-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) and an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(iv)(A) for the group II isolation, group III isolation, and Unit I emergency diesel generator (EDG) automatic start.

"Operations responded using emergency operating procedures and stabilized the plant in hot shutdown. Decay heat is being removed through the automatic depressurization system and the residual heat removal system.

"Coincident with the transient on Unit 1, Unit 2 experienced a trip of a reactor feed pump resulting in a runback of the reactor recirculation pumps. Unit 2 is currently stable at 80 percent power.

"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector and the Illinois Emergency Management Agency were notified."

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

On Unit 1, all control rods fully inserted on the scram and outboard main steam isolation valves closed on a loss of power.

The initial bus trip was caused by control power perturbations due to a ground on the associated battery system.

* * * UPDATE ON 5/20/2025 AT 1200 EDT FROM MATTHEW FRITCH TO SAMUEL COLVARD * * *

"Based on additional investigation, it has not been confirmed that the initial bus trip was caused by a ground on the associated battery system. The cause remains under investigation."

Notified R3DO (Szwarc)