Event Notification Report for May 23, 2025

AGREEMENT STATE - STUCK SOURCE

The following is a summary of information provided by the North Dakota Department of Environmental Quality (Department) via phone:

At 1315 CDT on May 15, 2025, the Department received a call from the radiation safety officer (RSO) of Iris NDT Inc. to report a stuck source in a SPEC-150 industrial radiography camera (serial number 2754). The 47.22 Ci Ir-192 sealed source became stuck when the operator attempted to withdraw it to the shielded position when the skid plate on the crank assembly buckled and became jammed. The RSO was able to successfully withdraw the source to the shielded position at 1344 CDT and the equipment was placed in an out of service status.

Initial reports indicate that no overexposure to employees or the public occurred, and an investigation is ongoing.

North Dakota Item Number: ND250001

AGREEMENT STATE REPORT - STOLEN GAUGE

The following information was provided by the California Department of Public Health via email:

"On May 15, 2025, the radiation safety officer (RSO) of Alta California Geotechnical, Inc. (Alta), contacted the Brea office of the California Department of Public Health to report a stolen moisture density gauge. The gauge was a CPN model MC-3 S/N MD30907144 (10 mCi, Cs-137; 50 mCi, Am:Be-241). The gauge operator discovered the gauge was missing on May 14, 2025, at approximately 1500 PDT, before they left the jobsite in Murrieta, CA. The operator noticed that the tailgate on the truck was down, the gauge case was open, and the gauge was missing. Alta personnel searched the surrounding area without locating the gauge and contacted the Murrieta Police Department to report the theft. A second search was performed the following morning with no success locating the gauge. The event was reported to the California Department of Public Health. The RSO confirmed that a trigger lock, securing the Cs-137 source in the shielded position on the gauge, was in place. The licensee's investigation into this event is ongoing and will be reviewed further by the California Department of Public Health."

California 5010 Number: 051525

* * * UPDATE ON 05/16/25 AT 1934 EDT FROM DONALD OESTERLE TO KERBY SCALES * * *

The following update was received from the California Department of Public Health via email:

"On May 16, 2025, the gauge was found and recovered. The gauge will be sent to the service provider to be evaluated."

Notified R4DO (Gepford), NMSS_Events_Notification, ILTAB, and CNSNS Mexico via email.

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 REPORT - STUCK SHUTTER

The following information was received from the Maine Radiological Control Program (RCP) via phone and email:

"On May 15, 2025, at 1142 EDT, Nine Dragons (ND) Paper contacted the Maine RCP and reported that the source shutter on a fixed nuclear level gauge was stuck in the open position and that the shutter on another gauge was failing to lock.

"While doing routine shutdown activities to dismount a unit for pipe replacement, it was discovered that one of the fixed mounted source units (source serial number: 551-2-90, 30 mCi of Cs-137) was not able to rotate the shutter to the closed position due to the shaft spinning for the shutter mechanism. Based on this finding, the lock and tag out of the unit was stopped and all work that was planned for the pipe replacement was cancelled. There was not any exposure to any personnel and the systems are still secure in the normal operation mode. ND Paper personnel barricaded the source holder and pipe piece so there would be no unintentional work on the pipe the unit is mounted to. The pipe diameter is too small to allow personnel entry, eliminating exposure risks.

"Later, while doing checks on other sources in the area it was discovered that another source (source serial number: 986-3-90, 20 mCi of Cs-137) was not able to lock its shutter. The shutter closes, as verified with a survey meter, but the locking mechanism will not operate to secure the shutter in the closed position. After discussing the issues with Berthold (the original equipment manufacturer), and mill operations, ND Paper decided to order a set of replacement holders and sources from Berthold. ND Paper will leave the units in place until Berthold is able to get replacement units and is able to schedule technicians to replace the malfunctioning gauges."

Maine RCP Event Report ID Number: ME (2025-003)

SOURCE LOST DURING SHIPMENT

The following information was provided by the licensee via phone:

A 0.182 TBq Ir-192 sealed source was lost in shipment by a common carrier. The package, a UN3332 Type A container with overpack, was picked up by the common carrier on April 25, 2025. The carrier's origin and interim sorting facilities have been searched and failed to locate the package. A search is on-going at the carrier's central sorting facility in Memphis, Tennessee. The source was in the process of being shipped to the source supplier in Vinton, LA for disposition.

THIS MATERIAL EVENT CONTAINS A 'Category 3' LEVEL OF RADIOACTIVE MATERIAL

Category 3 sources, if not safely managed or securely protected, could cause permanent injury to a person who handled them, or were otherwise in contact with them, for some hours. It could possibly - although it is unlikely - be fatal to be close to this amount of unshielded radioactive material for a period of days to weeks. These sources are typically used in practices such as fixed industrial gauges involving high activity sources (for example: level gauges, dredger gauges, conveyor gauges and spinning pipe gauges) and well logging. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf

AGREEMENT STATE REPORT - MEDICAL EVENT

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

"The Agency was contacted on 5/16/2025 by Advocate Christ Medical Center (Oak Lawn, IL), to advise of a medical administration of Y-90 microspheres that resulted in 100% of the dose not being administered. The administration occurred earlier that day and the reporting requirements were met by the licensee. Both the patient and the referring physician were notified. Inspectors will follow up next week to gather relevant details.

"The licensee advised that a patient was to be administered 1.129 GBq of Y-90 Theraspheres on 5/16/25. The authorized user reportedly initiated the administration but noticed the radiation monitor did not decrease as the procedure continued. The manufacturer's representative was on site and began to assist with troubleshooting. Ultimately, the administration was aborted, and PET-CT scanning indicated the microspheres were unable to leave the vial. PET-CT imaging of the patient further indicated no microspheres were administered. However, as the administration had been initiated; this is being reported as an under-dose."

Illinois item number: IL250022

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 - MEDICAL EVENT

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

"Northwestern Memorial Healthcare contacted the Agency on 5/15/25 at 1525 CDT to advise of a potential reportable medical event. During the afternoon of 5/15/25, a patient was administered a therapeutic dosage of 200 mCi of Lu-177 (Lutathera) which resulted in a total delivered dose that differed from the prescribed dose by more than 20 percent. The event was reported within the required time by the licensee. A reactive inspection will be conducted next week. An update received today, 5/16/25, indicates that the patient is reporting no adverse effects. The licensee's investigation remains ongoing.

"Initial information indicates the intravenous administration of 200 mCi of Lu-177 (Lutathera) into the antecubital vein of the patient's right arm resulted in 142 mCi (less than 71 percent of the prescribed dosage) delivered to the target organ/tissue. The underdosing was confirmed after imaging the patient subsequent to the procedure on 5/15/25. The licensee is continuing their investigation and dose assessment. The patient and the referring physician were notified of the event as required."

Illinois item number: IL250021

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

The Agency communicated that this could be a possible extravasation, as some fraction of the administered activity was found in the patient's arm, but this has not been confirmed. The target organ was the pancreas.

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 MOISTURE DENSITY GAUGE

The following information was provided by the California Department of Public Health, Radiologic Health Branch (the Department) via email:

"The Department was notified by Krazan and Associates' radiation safety officer that a Troxler model 3430 gauge (8 mCi Cs-137, 40 mCi Am-241/Be, serial number 35944) was lost from a gauge operator's vehicle in the city of El Cajon, CA. The gauge operator finished work and placed the gauge into the Troxler transit case without engaging the trigger lock on the gamma source's handle or locking the transit box latch. The transit case was left in the pickup truck bed next to the security box that is normally used during transportation.

"The gauge operator was distracted by a cell phone call and failed to return to secure the gauge and lift/secure the tailgate. The gauge operator drove the vehicle until recalling that the gauge was not secured, but it had already fallen from the truck. The operator retraced the route and eventually found the Troxler transit case on the side of the road, but the moisture density gauge, all associated tools, and paperwork from inside were missing.

"The licensee has notified local law enforcement and posted a reward on the City of El Cajon's social media page."

California event number: 051625

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

EN Revision Imported Date: 5/23/2025

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)

* * * UPDATE ON 5/22/2025 AT 1532 EDT FROM CONNER BEALER TO TENISHA MEADOWS * * *

"The scram was initially reported as manual; however, further investigation determined that it was automatically initiated."

Notified R3DO (Szwarc)

TECHNICAL SPECIFICATION REQUIRED SHUTDOWN

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

"On May 21, 2025, at 0656 CDT, River Bend Station (RBS) was operating at 100 percent reactor power when a plant shut down was initiated due to technical specification (TS) requirements. At 0324 on May 21, 2025, unidentified drywell leakage exceeded a 2 gallon per minute change over a 24-hour period. TS limiting condition of operation 3.4.5 condition 'C' was entered with a required action to verify the source of the unidentified leakage increase is not from service sensitive type 304, type 316 austenitic stainless steel, or other inter-granular stress corrosion cracking susceptible material within 4 hours. This required action could not be completed within the completion time.

"This event is being reported under 10 CFR 50.72(b)(2)(i) as an event or condition that results in a TS required plant shut down.

"The NRC Resident has been notified."

NOTICE OF UNUSUAL EVENT- FIRE IN BATTERY BANK

The following information was provided by the licensee via phone:

At 0359 CDT, Quad Cities Unit 2 experienced a fire in one of their battery cells during a planned discharge test. An Unusual Event (HU.3) was declared at 0413 CDT and the fire was extinguished by the fire brigade at 0422 CDT.

The effected battery bank was isolated at the time of the event and all other electrical systems are functioning normally. Unit 2 remains in Mode 1 at 100 percent power and Unit 1 was unaffected. No injuries have been reported.

The NRC Senior Resident Inspector, state, and local authorities have been notified.

The event was terminated at 0520 CDT due to the fire being out and no other plant equipment being affected.

Notified DHS SWO, FEMA Operations Center, CISA Central Watch Officer, FEMA NWC (email), DHS Nuclear SSA (email), CWMD Watch Desk (email).

PART 21 REPORT- CIRCUIT BREAKER DEFECT

The following information is a summary provided by the licensee via phone and email:

Twenty-one (21) breakers were installed at Arkansas Nuclear One (ANO) by Framatome Inc during a recent refurbishment. During the refurbishment, shorter bell cranks were installed to mitigate an identified interference. These shorter bell cranks result in a higher force being needed to close the breaker which could result in failure of the pushrods. In the event of a pushrod failure, the breaker may not trip when required, resulting in a substantial safety hazard.

Framatome has provided written correspondence to ANO to advise on this issue.

Model: 5-3AF-GEU-350-1200 Breaker

Affected plants: Arkansas Nuclear One

Gayle Elliott
Director, Licensing Regulatory Affairs
Framatome Inc.
gayle.elliott@framatome.com

TECHNICAL SPECIFICATION VIOLATION

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

"On May 22, 2025, at 1055 EDT, the Armed Forces Radiobiology Research Institue (AFRRI) TRIGA Mark F reactor experienced a high power scram during startup in steady-state mode under two rod automatic control. During power escalation, the log channel malfunctioned, failing to provide a period signal to the automatic control system. The reactor power level increased rapidly until high flux safety channels 1 and 2 caused an automatic scram, releasing control rods to shutdown the reactor. Due to rate of power increase, reactor power momentarily exceeded the steady-state limit of 1.1MW. All reactor protection systems functioned as designed. Reactor power was verified as decreasing; control rods were verified to be fully inserted. The safety limit, nor limiting safety system setting, were exceeded during the event.

"This event is reportable to the NRC under AFRRI Technical Specifications (T.S.) 6.5.2.b. and 6.5.2.c.

"The limiting condition of operations affected are T.S. 3.1.1. - Steady state power level exceeding 1.1MW, T.S. 3.2.1.a. - Log Channel inoperable, and T.S. 3.2.2. Table 3 - Failure of Rod Withdrawal Interlock for a period less than three (3) seconds.

"The NRC Project Manager will be notified."