Event Notification Report for August 13, 2025

AGREEMENT STATE REPORT - DAMAGED MOISTURE DENSITY GAUGE

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

The BRC was notified by the licensee's radiation safety officer at 1030 EDT that an in-use Model 3430 Troxler gauge was hit by a dump truck at a construction site. The source rod was reported to be in the exposed position but inside the ground. Both the handle and the top of the rod are broken. The area around the gauge has a 30-foot perimeter roped off. A BRC area inspector is responding.

Gauge Information:
Model: Troxler Model 3430
Activity: 8 mCi Cs-137, 40 mCi Am-241:Be

Florida Incident Number: FL25-076

AGREEMENT STATE REPORT - STUCK SHUTTER

The following is a summary of information provided by the Arkansas Department of Health, Radiation Control Section (ADH) via email:

On August 5, 2025, at 0933 CDT, the ADH was contacted by the licensee's assistant radiation safety officer to report that during quarterly shutter checks, they observed that a fixed gauge shutter was difficult to open. Subsequently, while attempting to operate it manually, it became damaged with broken bolts. The licensee contacted the manufacturer to initiate a repair or replacement. The manufacturer is recommending replacement.

All necessary safety precautions were taken during the inspection and operation attempt to prevent any further damage or risk. The source is still in service and is being used for continuous level reading. There were no unnecessary exposures.

Device Information:
Manufacturer: VEGA
Source Housing Model: SH-F1A
Source Housing Serial: 1694CP
Activity: 5 mCi
Isotope: Cs-137

Arkansas Event Number: ARK-2025-009

AGREEMENT STATE REPORT - LOST / MISSING SOURCES

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

"As a result of an ongoing Agency investigation into unresponsive general licensees, the Agency became aware today that two generally licensed fixed gauges, one containing 150 millicuries of Am-241 and the other 80 millicuries of Am-241, were likely disposed of as scrap in February 2023. The quantity of radioactive material involved, while unlikely to be dangerous to the public, is immediately reportable to the Agency and NRC. Agency staff will conduct a reactive inspection to determine if any additional information on the gauges is available (e.g., [are the items] still at the scrap yard or potentially auctioned during site closure).

"The licensee was operating at Glenview, IL, up until 2022. At that time, the company was in possession of an NDC Technologies model 102X (s/n 591181) containing 80 mCi of Am-241, and an NDC Technologies model 103X (s/n 591171) containing 150 mCi of Am-241. According to the facility's property manager, the facility closed in August 2022. Reportedly, the contents of the building were auctioned off and all remaining items were recycled for scrap in February 2023. The property manager stated that at the time they did not realize there was radioactive material in the scrap. This investigation remains ongoing."

Illinois Item Number: IL250032

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 is a summary of information provided by the Louisiana Department of Environmental Quality (LDEQ) via email:

The licencee's radiation safety officer notified LDEQ of an equipment malfunction, which occurred at their facility on August 6, 2025, at approximately 0930 CDT. During a routine shutter check, the shutter of a fixed gauge became stuck in the closed position. The vendor conducted a site visit and assessment where he noted that the bolt fastening the rotor handle sheared, leaving the rotor inoperable. The shutter was left in the open position while awaiting replacement. The licensee intends to order a replacement source holder and shield, remove the existing source holder, and prepare it for disposal. The gauge shutter is now stuck in the open position. No exposures in excess of regulatory limits took place. The licensee is monitoring radiation levels around the gauge and vessel and will notify the LDEQ of incident status changes.

Device Information:
Manufacturer: VEGA
Source housing model: SH-F1A-45
Device serial number: 74127
Source serial number: 7474CO
Activity: 300 mCi
Isotope: Cs-137

Louisiana Event Report Number: LA20250005

AUTOMATIC ACTUATION OF THE 'A' EMERGENCY DIESEL GENERATOR

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

"On August 11, 2025, at 0212 EDT, VC Summer Unit 1 was in Mode 1 at 100 percent power when the 'A' emergency diesel generator (XEG0001A) automatically actuated in response to undervoltage indications on Bus `1 DA'. Bus `1 DA' remained energized from its normal offsite power source. The XEG0001A was secured at 0302 EDT and realigned for auto start.
"Dominion Energy South Carolina (DESC) is actively investigating to determine the cause of the transient at this time.
"This event is being reported as eight-hour notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the 'A' emergency diesel generator."
The NRC Resident Inspector was notified.

TECHNICAL SPECIFICATION REQUIRED SHUTDOWN

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

"At 1621 EDT on 8/12/2025, a technical specification required shutdown was initiated at Davis-Besse Nuclear Power Station Unit 1. Technical specification limiting condition for operation 3.3.11 for steam generator (SG) low level instrumentation channel requirements was not met, and condition 'B' was entered on 8/12/2025 at 1600 with required actions to be in mode 3 with a completion time of 6 hours and be in mode 4 with a completion time of 12 hours. This event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(i). 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:

The affected SG level instrumentation is for emergency feedwater automatic initiation. The instruments were declared inoperable due to a reference leg leak in containment.