Event Notification Report for August 12, 2025

EN Revision Imported Date: 8/12/2025

EN Revision Text: LOST TRITIUM EXIT SIGNS

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

"Two tritium exit signs cannot be located at Bridger Coal Mine in Point of Rocks, Wyoming. The signs are believed to have been returned to the manufacturer following use, but there is no paperwork to confirm. Efforts to ascertain knowledge of the purchase or return of the devices from the manufacturer were fruitless. Bridger Coal Mine does not have intentions now, or in the future, to possess generally licensed devices."

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

Each exit sign contained 7.5 curies of tritium.

* * * UPDATE ON 08/11/2025 AT 1606 EDT FROM VICTOR LOUDERBACK TO ROBERT THOMPSON * * *

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

One of the missing signs was located by the licensee. Disposal is being coordinated by a vendor.

Notified R4DO (Agrawal), NMSS Events Notification (email), ILTAB (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

EN Revision Imported Date: 8/12/2025

EN Revision Text: AGREEMENT STATE REPORT - OVEREXPOSURE

The following information was provided by the Maryland Department of the Environment (MDE) via phone and email:

"On Friday, June 27, 2025, at 1249 EDT, MDE Program Manager received an email from the radiation safety officer (RSO) at Johns Hopkins University Radiation Control Unit, regarding a radiation overexposure incident involving a declared pregnant worker at the Johns Hopkins Bethesda PET facility.

"The RSO reported that a PET technician received the following radiation doses over the past three months:

"Fetal dose: 13.149 rem
"Whole body dose: 29.966 rem
"Extremity (ring) dose: 6329 rem

"Following the notification, the MDE contacted the RSO by phone to obtain additional details about the incident.

"The RSO explained that the employee's radiation exposure levels remained within acceptable limits until mid-March 2025. At that time, the technician began receiving higher-than-typical doses. The employee was informed when elevated exposure levels were initially observed in April 2025 dosimetry records.

"Upon reviewing the May 2025 dosimetry reports, the Radiation Control Office observed that the exposure levels were significantly elevated. As a result, the June 2025 dosimetry was expedited, which confirmed doses exceeding investigation thresholds. The employee was promptly notified of the dose results and was immediately removed from any work involving radioactive materials. The RSO has initiated a root cause investigation and will notify the MDE as required. This communication serves as a preliminary notification; MDE will follow up on the case and will provide further updates as appropriate."

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

The overexposure was limited to one worker as two other workers' dosimetry indicate normal exposures. It is unknown at this time what radiopharmaceutical was involved or if there is an indication of spread of contamination. MDE does plan to perform a reactive inspection.

* * * UPDATE ON 6/27/2025 AT 1858 EDT FROM KRISHNAKUMAR NANGEELIL TO SAMUEL COLVARD * * *

The following summary of information was provided by the Maryland Department of the Environment (MDE) via phone and email:

The facility and license number is Johns Hopkins Imaging, Bethesda (RAML #31-314-01). The radiopharmaceuticals used contains F-18 and G-68. MDE called the facility RSO and the RSO determined that there is no indication of a spill or spread of contamination at the facility.

Notified R1DO (Arner), NMSS Events (email), NMSS (Silberfeld).

* * * UPDATE ON 8/4/2025 AT 1400 EDT FROM KRISHNAKUMAR NANGEELIL TO JON LILLIENDAHL * * *

The following summary of information was provided by the Maryland Department of the Environment via email:

Following further investigation, the facility received updated dosimetry reports from their contractor. These values were confirmed through reanalysis using multiple instruments. Based on this reassessment, the originally reported doses were found to differ slightly from the earlier reported values. Specifically, the updated fetal dose is 14.790 rem.

Notified R1DO (Henrion), NMSS Events (email), NMSS (Allen).

* * * UPDATE ON 8/11/2025 AT 1607 EDT FROM MARTIN LODGE TO TENISHA MEADOWS * * *

The following summary of information was provided by the Maryland Department of the Environment via email:

The extremity (ring) dose is 6329 mrem (i.e. 1000 times lower), instead of 6329 rem.

Notified R1DO (Bickett), NMSS Events (email), NMSS (Fisher).

EN Revision Imported Date: 8/12/2025

EN Revision Text: AGREEMENT STATE REPORT - POTENTIAL OVER EXPOSURE

The following report was received by the Georgia Radioactive Materials Program via email:

"The licensee's radiation safety officer called and stated that, during a high dose rate procedure, the nurse got stuck in the vault and was behind the CT [computed tomography] lead shielding. The licensee plans to send out her dosimetry badge to be processed for dose received and perform a pregnancy test.

"[The Georgia Radioactive Materials Program] will follow up with more information as we receive it."

Additional information: The equipment involved was a GammaMedPlus 3/24iX remote brachytherapy afterloader containing a Ir-192 source with an activity of 3.158 curies.

* * * UPDATE ON 08/11/2025 AT 1305 EDT FROM STACY ALLMAN TO TENISHA MEADOWS * * *

The following report was received by the Georgia Radioactive Materials Program via email:

"The licensee sent in the final report along with the dosimetry for the nurse involved in the incident. The nurse was in an adjacent procedure room that connects to the HDR [high dose rate] vault. It is used for gynecologic preparation and is shielded for CT [computed tomography] energy, but not Ir-192. The nurse was restocking the room and did not realize the treatment had started. The procedure was interrupted by the team upon hearing [the nurse] call out. [The nurse] was in the room 10 out of the 11 minutes. [The nurse] estimated unshielded dose was 12 mRem. The nurse's TLD [thermoluminescent dosimeter] badge read minimum exposure after the incident. The licensee is updating their procedures and check list to include checking all adjacent rooms before beginning the procedure. They will be retraining the staff on HDR safety procedures and plan to evaluate an audible alarm to accompany the beam on lights for the vault. This has been determined not to be a reportable event."

Notified R1DO (Bickett) and NMSS Events (email)

Georgia Incident Number: 104

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

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.