Event Notification Report for April 24, 2025

EN Revision Imported Date: 5/16/2025

EN Revision Text: AGREEMENT STATE REPORT - MEDICAL EVENT

The following information was provided by the Kentucky Department for Public Health (the Department) via email:

"On 4/24/2025, permanent implant brachytherapy (isotope unknown at this time) was administered without a written directive. A pre-treatment plan was completed and approved by the authorized user (AU), and treatment was administered on this basis by the AU, but no pre-implant or post-implant written directives meeting the requirements of 10 CFR 35 were completed. The event was identified during the post implant dosimetry process on 5/6/2025.

"This event is under investigation. University of Kentucky has temporarily paused implants while they complete their assessment and implement corrective actions.

"The written report will follow as required in 15 days. A reactive inspection will be performed by the Department."

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.

LOST TRITIUM EXIT SIGNS

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

Two tritium exit signs were reported lost or missing during a recent safety emergency lighting audit conducted on April 24, 2025. Despite a thorough internal review and inspection of storage, disposal, and installation records, the devices were unable to be located or disposition verified.

The licensee is in the process of updating all emergency exit signage and lighting. Additionally, they are removing the remaining six (6) self-luminous exit signs from their facility and will return them to lsolite for proper disposal in accordance with regulatory guidelines. To prevent any recurrence, the facility will no longer purchase or utilize self-luminous signage in the future.

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

There is no information of previous inventory records since the initial delivery around April 2016. Information about this event was previously reported to the NRC Region III office on May 12, 2025.

Maker: Isolite
Model Number: SLX-60
Serial Numbers: H56081 and H56088
Estimated Activity: 0.281 TBq tritium (H-3) or 7.59 Ci/ sign (TOTAL: 0.562 TBq or 15.18 Ci)
Date of Manufacture: March 2016

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

FITNESS FOR DUTY - ALCOHOL CONTAINER FOUND IN PROTECTED AREA

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

"On April 24, 2025, at approximately 2321 CDT, an empty 100 mL alcohol bottle was found in the protected area by a contract employee. Site security was notified and took possession of the bottle which was removed from the protected area.

"The NRC Resident Inspector was notified."

EN Revision Imported Date: 7/14/2025

EN Revision Text: PART 21 REPORT - SOLENOID VALVE FAILS TO OPERATE AFTER EXTENDED DE-ENERGIZATION

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

This report relates to the failure of a single air-operated valve identified by Dominion Energy at North Anna due to failure of the associated solenoid valve. The solenoid valve periodically failed to reposition, or only partially repositioned, after periods of extended de-energization.

As part of testing, the ASCO NP8321 solenoid valve series and all ASCO NP-series solenoid valves were qualified to sit in a normally energized position and were not tested for extended periods of de-energization. The U-cup seal was tested and ASCO determined that this U-cup seal experienced performance limitations at low air operating pressures (below 40 psi) and the valve did not shift completely to an energized state.

An alternative valve (NP8300) is recommended by ASCO for this customer application. In the interim, ASCO recommends increasing the inlet air pressure to the valve to at least 80 psi not to exceed the maximum 150 psi to conservatively ensure proper operation of the NP8321 series valve in a de-energized state.

ASCO concludes based on design and known operating experience that only the NP8321 model valve exhibits this condition.

ASCO does not have adequate knowledge of the actual installation and operating condition of this valve to determine whether this condition would create a `substantial' safety hazard as defined in 10 CFR 21.3. The report is intended to provide investigation results and recommendations. Each end user needs to perform their own evaluation based on the information provided in this notification.

Bryan Causey
Quality Engineer
Bryan.Causey@Emerson.com

The only plant known to be affected at the time of the report is North Anna.

* * * UPDATE ON 07/11/2025 AT 0907 EDT FROM BRYAN CAUSEY TO IAN HOWARD * * *

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

ASCO performed extensive testing on this valve with a variety of U-cup seals and found all U-cup seals used for the NP8321 series have low pressure de-energized dormancy performance limitations.

For applications where the valve is at 80 psi, ASCO will be updating guidance to indicate that a minimum pressure rating of 80 psi must be maintained when switching from the de-energized state to the energized state for normally closed valves. For normally open valves, 80 psi must be maintained when switching from the energized state to the de-energized state. ASCO ensures application at or above 80 psi would meet its equipment qualification requirements.

For applications between 40 and 80 psi the utility has not observed any low-pressure dormancy issues on valves that have already experienced the applications longest possible period of de-energization, ASCO advises that the valve remain in service for the rest of its equipment life, during this time ASCO recommends looking for an appropriate alternative valve and solution for this system. ASCO recommends an NP8300 or NP8316 valve as a suitable replacement. For applications at or below 40 psi, the utility should consult with ASCO at the earliest opportunity.

The NP8300 is a potential replacement for the NP8321 series but it is not a drop-in replacement. The NP8300 series consumes twice the wattage of NP8321 and has a lower flow rate. If the lower flow and higher wattage of the NP8300 are acceptable limitations for the utility's application, then ASCO would recommend a NP8300 valve.

If the application requires the same wattage and can manage higher flow, a NP8316 can replace a NP8321 but the higher flow rate may require changes to the specific system in place. The NP8316 does have a lower minimum operating pressure differential of just 10 psi instead of 15 psi, but the flow is several times higher than the NP8321. For this solution to work, the system would need to be tolerant of this higher flow and ensure that the minimum operating pressure differential of 10 psi (measured between in the inlet port and exhaust port) is maintained with appropriate piping/regulators and exhaust pipes capable of ensuring that the minimum pressure is maintained. This could include changing out piping and regulators for larger sized pipes and regulators to match the higher Cv [valve flow coefficient] of the NP8316 series.

ASCO concludes that for applications at or above 80 psi, the NP8321 series valve meets its full equipment requirements. For applications below 80 psi, ASCO recommends replacing the value based on the above guidelines.

Notified R2DO (Davis) and the Part 21 groups (email).

AGREEMENT STATE REPORT - LOSS OF RADIOACTIVE MATERIAL

The following information was provided by the State of Florida Bureau of Radiation Control (BRC) via email:

"BRC received notification from [a representative of] Environmental Health and Safety for Florida A & M University, that a scintillation counter with an embedded Cs-137 external quench monitor source was improperly disposed of. [The representative] states the professor in charge of the laboratory requested the item's removal, and it was disposed of as a piece of retired equipment without recognizing the presence of the radioactive material. This error was identified by [the radiation safety officer on] 7/29/25. [The licensee] could not locate the serial number for the item."

The device is a Beckman Coulter Model number LS6500 and contains a 30 mCi Cs-137 source.

Florida Incident Number: FL25-079

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