Event Notification Report for March 17, 2025

AGREEMENT STATE REPORT - POTENTIAL DAMAGE TO A TROXLER GAUGE

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

BRC was notified by Florida Highway Patrol (FHP) dispatch at 1036 EDT on 03/18/2025 that an FHP trooper was on the scene of a multi-vehicle accident involving a pickup truck transporting a soil moisture density gauge. BRC spoke to the FHP trooper on-scene, who reported the gauge case was intact, with no apparent damage, still secured in the back of the pickup truck.

A BRC inspector responded to the scene and confirmed the gauge and case were both intact and secure, with no apparent damage. No injuries were reported to the driver of the truck. Radiation readings of the gauge were normal, and a swipe survey revealed no leakage. The gauge was released to the owner.

The gauge is a Troxler, model 3440, serial number 25401, containing a 40 mCi Am-241/Be source, serial number 47-21689, and an 8 mCi Cs-137 source, serial number 75-8235.

FL incident report number: FL25-023.

FITNESS FOR DUTY

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

"At 1059 [CDT] on March 18, 2025, it was determined that a licensed operator failed a [random] test specified by the fitness-for-duty testing program. The individual's authorization for site access has been terminated.

"The NRC Resident Inspector has been notified."

EN Revision Imported Date: 4/7/2025

EN Revision Text: SECONDARY CONTAINMENT BOUNDARY INOPERABLE

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

"At 1026 [EDT] on March 18, 2025, it was discovered that the secondary containment boundary door was found fully open, rendering the secondary containment boundary inoperable, therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72 (b)(3)(v). The door was closed at 1029 on March 18, 2025, and the secondary containment boundary was declared operable.

"There is no impact on the health and safety of the public or plant personnel.

"The NRC Resident Inspector has been notified.

"There has been no impact to Unit 2 and Unit 3 continues to operate at 100 percent power."


* * * RETRACTION ON 04/04/25 AT 1049 EDT FROM RYAN ROBILLARD TO JOSUE RAMIREZ * * *

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

"This report retracts the 8-hour notification made on March 18, 2025, for NRC Event Number EN #57615.
"NRC Event report number 57615 describes a condition at Millstone Power Station Unit 3 (MPS3) where a secondary containment boundary door was found fully open, rendering the secondary containment boundary inoperable. This condition was reported in accordance with 10CFR 50.72(b)(3)(v)(D) as a condition that could have prevented the fulfillment of a safety function to mitigate the consequences of an accident.
"Upon further review of the conditions that existed at the time, MPS3 has concluded that the door was not blocked open. The time duration from the activation of the door security alarm to the arrival of security personnel and the subsequent closure of the door was less than four minutes. The door was left unattended for less than 40 seconds, which is less than the five-minute criteria for entry and egress without special provisions. The supplementary leak collection and release system drawdown test has sufficient margin to accommodate this unattended door time. The evaluation concluded that the secondary containment boundary remained operable throughout this event and did not lose the ability to perform its safety function to control the release of radioactive material and mitigate the consequences of an accident.

"The basis for this conclusion will be provided to the NRC Resident Inspector."

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

This event was originally reported in accordance with 10CFR 50.72(b)(3)(v)(D) and 10CFR 50.72(b)(3)(v)(C). The licensee confirmed that the retraction is applicable to both notifications.

Notified R1DO (Bickett)

FAILED FITNESS FOR DUTY TEST

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

"At 0930 EDT, March 18, 2025, it was determined that a contract supervisor failed a [random] test specified by the fitness-for-duty testing program. The individual's authorization for site access has been terminated.

"The NRC Resident Inspector has been notified."

AGREEMENT STATE REPORT - STOLEN MOISTURE DENSITY GAUGE

The following information was provided by the Texas Department of State Health Services (the Department) via phone and email:

"On March 17, 2025, the Department received a notification from the licensee regarding the theft of a moisture density gauge. The stolen gauge is a Troxler 3430 containing an 8 mCi Cs-137 sealed source and a 40 mCi Am-241/Be sealed source. The theft is believed to have occurred between 1700 CDT on Saturday, March 15, and 0630 CDT on March 17, 2025. According to the licensee, a technician worked at a scheduled site in Fulshear, Texas on March 15, 2025, but failed to return the gauge to the office for storage. Instead, the technician without approval took the gauge home and left it in the back of a truck. The gauge was stored in its transport container, secured with double locks and placed in the uncovered bed of the truck. The licensee stated that the thieves cut both locks before stealing the gauge in its container. At around 0630 CDT on March 17, 2025, the technician discovered that the gauge had been stolen. The technician immediately reported the theft to the licensee's radiation safety officer and the Houston Police Department. The licensee is currently investigating the matter. The licensee reported that there is no risk of additional radiation exposure to members of the public.

"Additional Information will be provided in accordance with SA300."

Texas Incident Number: I-10183
NMED number: TX250019

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 - DAMAGED SEALED SOURCE

The following information was received from the Illinois Emergency Management Agency (the Agency) via email:

"The Agency was contacted on March 17, 2025, by Alton Steel Inc., to advise of an incident earlier that day in which molten steel overflowed and damaged a 2.3 millicurie Berthold P-2608-100 Co-60 sealed source. Agency staff performed a reactive inspection the same day and determined the damage was limited to the source's pinned-on threaded connector (i.e., not the `active' portion of the source containing the Co-60 wire). Workers appropriately implemented updated emergency procedures, stopped production, isolated the impacted source/mold and notified the radiation safety officer. Extensive Agency surveys and a review of actions taken indicate there were no exposures or site contamination as a result of this incident.

"Both pieces of the source were recovered and placed into secure storage. Shielding was adequate to keep unrestricted areas below 2 mrem per hour. Surveys of the casting mold, the lid, the casting floor, produced billets, and casting remnants evidenced no contamination. The broken piece of the source evidenced no activity, consistent with expectations after a review of the engineering drawings of the source. Due to fouling of the source, the serial number could not be immediately read. A qualified service provider will be contacted to perform leak tests and obtain the source serial number.

"Notably, the licensee has had three similar incidents in which sealed sources were damaged as a result of casting overflows. The root cause is an inherent design issue with the continuous casting molds where severe overflows can penetrate a lubrication circuit and flow directly down the dip tube holding the sealed source. As a result of previous enforcement action, the licensee has completed engineering and prototyping of an improved design which will protect the sealed sources. Agency staff have asked for an expedited timeline and will seek appropriate enforcement action for implementation. Agency action on the license, enabling these changes, will be issued March 18, 2025. Previously identified concerns of personnel exposure and site contamination have been addressed through updated training and new procedures."

Illinois Incident Number: IL250011