Event Notification Report for December 01, 2025

AGREEMENT STATE REPORT - MEDICAL EVENT

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

"On 10/30/25, the licensee was treating a patient with Y-90 microspheres to a liver lobe in 3 dosages. The first two dosages were successfully administered, but the third dosage did not deliver successfully, with essentially none of the dosage reaching the target. Instead, the majority of the dosage was retained in the administration apparatus with some having leaked out, resulting in contamination of the treatment room and treating personnel. While the licensee reported this event to RHB on 11/1/25, it was reported by email and not directed to the correct RHB sub-organization, nor was the email clear regarding the event. This resulted in the significant delay in reporting this event to the NRC.

"RHB is still investigating this event."

California 5010 Number: 110125


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.

SHIPMENT EXCEEDS SURFACE CONTAMINATION LIMITS

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

"On November 21, 2025, at 0835 CST, River Bend Station (RBS) was operating at 78 percent reactor power when the [radioactive waste] shipping department received a cask from the Waste Control Specialists disposal facility in Andrews County, TX via [a common carrier]. A smear sample was collected and exhibited surface contamination above the Department of Transportation (DOT) limits, specified in 49 CFR 173. The carrier was notified at 1713 CST.

"The surface contamination exceeded 24,000 [disintegrations per minute per centimeter squared] for beta gamma [activity].

"Supervision was immediately contacted and placed the shipment into a radiological controlled area.

"An investigation was performed to the extent of the condition of the loose surface contamination of the cask to determine if it was isolated to the immediately accessible areas of the cask due to an installed rain cover. The investigation concluded that the condition was extended to the surface of the cask where the average surface area exceeded DOT limits.

"This condition is immediately reportable to the NRC headquarters operations center per 10 CFR 20.1906(d)(1)."

OFFSITE NOTIFICATION

The following is a summary of information that was provided by the licensee via phone:

On 11/22/2025 at approximately 1340 EST, a plant worker sustained a leg injury on site at Vermont Yankee and was transported to a local hospital. The injured worker was verified to not be contaminated. Vermont Yankee notified the Department of Homeland Security and local law enforcement to inform them of the situation due to emergency medical response personnel responding on site. Vermont Yankee is making this report to the NRC per 10 CFR 50.72(b)(2)(xi) for offsite notification to other government agencies.

The NRC Regional Inspector was notified.


* * * RETRACTION ON 11/24/2025 AT 1037 FROM TOM SILKO TO JOSUE RAMIREZ * * *

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

After further review, Vermont Yankee (VY) has determined that the event was not reportable. Therefore, VY is retracting the report. The basis for the retraction is: Notification to the NRC was made based on reporting to another government agency (The Vermont Department of Homeland Security), however, the reporting to the Vermont Department of Homeland security was not required per VY implementing procedures.

Notified R1DO (Bickett) and NMSS Events Notifications (Email).

LOST BRACHYTHERAPY SEEDS

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

"On November 19, 2025, Pd-103 seeds were retrieved from secure storage and brought directly to the operating room in accordance with established protocol. Pre-procedure planning; including review of the treatment plan, seed mapping, and completion of the written directive; was completed prior to patient arrival.

"The patient was brought to the operating room at 1145 [EST]. A standardized time-out was performed to confirm correct patient, procedure, antibiotic administration, fire safety considerations, and seed verification. The patient was anesthetized and positioned, and the procedure began at 1151 and ended at 1207. An active, collaborative seed count was maintained throughout the case.

"During the debriefing phase, the radiation oncologist authorized user, surgical technologist, and nursing staff verbally confirmed the number of seeds implanted, the number of needles used, and the remaining seeds to be returned to storage. The patient was then transferred to recovery.

"During post-procedure room turnover, the surgical technologist reported difficulty removing the final seed cartridge from the applicator. She attempted to remove it by unscrewing the cartridge holder but was unsuccessful. After reassembling the device, she handed it to the radiation oncologist, who was able to partially remove the cartridge. The portion of the cartridge that remained connected to the applicator is presumed to have contained the unused seeds. The applicator was then sent to the central processing department (CPD) for sterilization with part of the cartridge still lodged inside. It was processed through CPD as routine.

"Based on the investigation, it is presumed that during the sterilization process the [eight] remaining Pd-103 seeds became dislodged from the cartridge assembly. Once separated, the seeds would have entered the wastewater stream and been carried into the sanitary sewer system, resulting in their unintentional disposal.

"Below are the calculations documenting the classification of reporting requirements.

"Sealed source certificate Pd-103 certified the following:

"Activity range: 2.59 - 2.80 mCi

"Maximum activity: 2.80 mCi x 8 seeds = 22.4 mCi

"Regulations for immediate reporting - Pd-103 100 (Part 20 Appendix C) x1000=100000 = 100 mCi
Total activity lost - 22.4 mCi - not reportable under 20.2201(a)(i)

"Regulations for report within 30 days - Pd-103 100 (Part 20 Appendix C) x10=1000 = 1 mCi
Total activity lost - 22.4 mCi - reportable under 20.2201(a)(ii)"

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 - LOST EXIT SIGNS

The following information was provided by the New Jersey Bureau of Environmental Radiation Radiological & Environmental Assessment Section via phone and email:

"During a site-wide inventory reconciliation, the licensee determined that 26 [of the] licensee's tritium exit signs could not be located. While a comprehensive search was conducted, it was ultimately determined that the signs may have been misplaced or removed during prior renovation or decommissioning activities. The signs were declared missing on November 20, 2025.

"The site is actively engaged in removing all tritium exit signs that remain on-site through a licensed waste broker. They will be replaced with non-radioactive signs."

Manufacturer: Various
Model number: Various
Total estimated activity: 272 Ci
Isotope: H-3

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