Event Notification Report for April 30, 2026

EN Revision Imported Date: 4/29/2026

EN Revision Text: PART 21 - DEFECTIVE SOLENOID VALVE ASSEMBLY

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

Forty incorrectly assembled solenoid valve assemblies were sent to Trillium Flow Technologies (TFT). On September 19, 2025, following a report by TFT that one of their customers was experiencing functionality issues, testing showed that these parts contain a defective bottom insert seal that has not been fully seated into the plunger area. This could result in improper functioning of the solenoid valve. Trillium Flow Technologies has been informed, and a recall of the potentially defective parts has been initiated.

Corrective actions include a recall of effected parts, implementation of additional training and quality control processes

Hanna Part Number: N606-00200-000
TFT Part Number: 27791650C003

Contact Information:
Mujtaba Khan
Quality Manager
262-764-8262

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

Hana Cylinders is unaware of any sites being affected.

* * * UPDATE ON 04/27/2026 AT 1520 EDT FROM JESSIKA WHEATLEY TO ROBERT THOMPSON * * *

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

The licensee reported that Trillium Flow Technologies discovered an additional lot of solenoid valve assemblies exhibiting the same functional issues during handling and/or installation as reported in 2025. The solenoid valve assemblies identified in this update were supplied under a different purchase order and were not part of the population addressed in the original notification. The valve assemblies in this additional lot do have the same part numbers as those addressed in the 2025 report.

This additional lot will be returned to the licensee for evaluation.

A list of potentially affected customers was not provided.

Notified R3DO (Sanchez Santiago), Part 21/50.55 Reactors (email), Part 21 Materials (email).

EN Revision Imported Date: 4/30/2026

EN Revision Text: LOST SOURCE

The following information was provided by the licensee via phone:

In 2023, an Agilent gas chromatograph had its source (15 mCi Ni-63) removed and was sent for recycling. The source was placed in storage on-site. In March 2026, the licensee began returning all stored material to the manufacturer for disposal. It was determined that the stored source contained no radioactive material and the Ni-63 could not be located. After performing multiple searches, the source was deemed lost at 1445 EDT on April 2, 2026. The licensee continues its search.

* * * UPDATE ON 04/03/2026 AT 1328 EDT FROM SHANE ROGERS TO SAMUEL COLVARD * * *

The following is a summary of information provided by CDC NIOSH via email:

During an August 2025 NRC license-renewal inspection, one Ni-63 source (15 mCi) was believed to have been located but not fully confirmed. A researcher later identified the equipment to which the source originally belonged. In March 2026, efforts began to dispose of or return three stored Ni-63 sources, with responsibilities transitioning between staff members as disposal and return procedures were initiated.

On April 2, 2026, staff reported that one Ni-63 source (sealed source serial U28862, detector serial U28862, sealed source model NER-004P, detector model G2397-65505) was missing from the locked storage cabinet. It was noted that the gas chromatograph from which the source had been removed had been sent for recycling several years earlier, and there was concern that the source may have been inadvertently sent with the equipment. Barcode information for the equipment was located and forwarded to support confirmation of its recycling history.

On April 3, 2026, it was verified that the gas chromatograph had been sent for recycling in August 2023 to a commercial recycling facility. A full inspection of the locked storage cabinet confirmed the missing source was not present, although certification paperwork was found. An access review indicated that while many individuals had access to the laboratory space, access to the locked cabinet was restricted to authorized personnel only. The recycling company reported that any radioactive source found in received equipment would normally be returned. The recycling company also stated that equipment from the organization is typically stripped prior to arrival and that any remaining material is transferred to another facility in a different state.

Notified R1DO (Bicket), NMSS Events Notifications (email), and ILTAB (email).

* * * UPDATE ON 04/29/2026 AT 0847 EDT FROM SHANE ROGERS TO CHRISTOPHER PRESCOTT * * *

The following is a summary of information provided by CDC NIOSH via email:

The Ni-63 source has not been recovered and is considered lost. Based on available information and review of historical practices and equipment excessing processes, the source is believed to have been inadvertently disposed of as scrap or waste during equipment disposition activities; however, its exact disposition cannot be confirmed. The source is no longer under the control of the licensee.

Notified R1DO (Dentel), NMSS Events Notifications (email), and 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

AGREEMENT STATE REPORT - STUCK SOURCE

The following information was provided by the North Dakota Department of Health via email:

"Apave America Inc., North Dakota license number 33-56806-01, reported an incident that occurred on April 21, 2026, at 2200 CDT involving an irretrievable source at the Marathon refinery in Mandan, North Dakota. The event involved a SPEC-150 industrial radiography device (serial no. 2800) containing a 71 Ci (2638 GBq) sealed Ir-192 source (serial no. GC1214).

"During an exposure on the Ultra Former Unit, the radiographer discovered that the crank had become stuck and could not return the source to its shielded position after the exposure. The radiographer immediately established a barricade at the public-dose distance for a one-hour exposure, maintained continuous surveillance, and notified the company radiation safety officer and Marathon Operations.

"The radiographer then obtained the necessary tools and moved the crank assembly to a shielded area behind a concrete wall for disassembly. After removing the crank handle and the faceplate screws, the radiographer found that a small roll pin had become wedged between the drive cable and the gear. This pin was not part of the crank assembly and is not normally attached to it.

"After removing the pin, the radiographer successfully cranked the source back into the shielded position. The crank assemblies were then tagged out for repair."

North Dakota Event Number: ND260002

UNANALYZED CONDITION - PELLETS FOUND IN DRAIN PIPING

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

"On April 22, 2026, at approximately 0700 EDT, engineering initiated planned integrity inspections of the pellet sintering furnace cooling water drain piping as part of the established aging management program. This evaluation of piping conditions supports long-term refurbishment or replacement planning. At approximately 0930 EDT, inspection activities were stopped when personnel observed approximately nine fuel pellets embedded in scale within a section of 4-inch drain piping, along with two isolated pellets located a few feet farther downstream where the piping diameter increases to 6 inches.

"The condition was reported to environmental, health, and safety. Inspection activities were halted, and the system was placed in a safe condition. Pelleting area operations were already down for the upcoming inventory period and will remain down pending further investigation. The condition was entered into the corrective action program for further analysis and evaluation. At this time, the investigation is ongoing, and this report is being submitted per 10 CFR 70, Appendix A (b)(1), as a potential unanalyzed condition in the integrated safety analysis (ISA). There is no impact to the public or the environment."

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

The sintering furnace cooling water drain piping drains to a monitored chemical cooling tower. No pellets are expected in the drain piping. There was no spread of contamination or environmental release.

LOST SOURCE

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

"On March 26, 2026, at 2003 EDT, during a required semiannual source inventory, Hatch discovered that a radioactive source was missing. The source had been positively accounted for during the September 2025 inventory.

"The material involved is a National Institute of Standards and Technology traceable mixed-gamma calibration source (source ID 0091-00-00). It is a solid epoxy source contained in a 125 mL plastic bottle and was decay-corrected to approximately 0.22 microcuries at the time of discovery.

"The lost radioactive material includes americium-241 in excess of 10 times the quantity specified in appendix C to part 20. Therefore, this is reported as a nonemergency loss of licensed material under 10 CFR 20.2201(a)(1)(ii).

"The NRC Resident Inspector has been notified."

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

"On April 23, 2026, the Department was notified by the licensee that during routine testing, the shutter of a Ronan Engineering model SA-F37 gauge failed to close. Open is the normal position of the shutter. The gauge contains a 100 mCi (original activity) cesium-137 source. The licensee reported the gauge does not present an exposure risk to any individual. The licensee reported that a service company has been contacted to repair the gauge.

"Additional information will be provided as it is received in accordance with SA - 300."

Texas incident number: 10283

AGREEMENT STATE REPORT - STUCK SHUTTER

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

"On April 23, 2026, the Agency received notification from the licensee regarding a stuck source shutter on a fixed nuclear gauge. The gauge is an Ohmart Vega SHF1A model, containing a 20 millicurie cesium-137 sealed source. The licensee reported that during routine plant maintenance checks conducted on April 23, 2026, technicians identified a shutter that was sticking and determined that one of the bolts on the shutter had broken, causing the shutter to become stuck in the open position. Open is the normal operating position. No workers or members of the public were exposed to radiation because of this event. The licensee further stated that arrangements had been made for a service provider to repair the gauge on April 27, 2026.

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

Texas Incident Number: 10284