Event Notification Report for April 08, 2026

LOST RADIOACTIVE MATERIAL IN TRANSIT

The following information was provided by the licensee via phone:

On March 5, 2026, at 1224 CST, River Bend declared a radioactive materials shipment lost after it was supposed to be delivered by February 2, 2026. The last time the shipment was scanned in the tracking system was on February 11, 2026, at the [common carrier] distribution warehouse in Pearl, MS. The device is a digital acquisition unit inside a Pelican case which contains 122 microcuries of Co-60. River Bend plans on notifying the State of Mississippi regarding the lost material. Because the quantity of radioactive material lost exceeds 10 times the quantity specified in appendix C to part 20, this is being reported as a non-emergency loss of licensed material.

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

INVALID SPECIFIED SYSTEM ACTUATION

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

"This 60-day telephone notification is being made per the reporting requirements specified by 10 CFR 50.73(a)(2)(iv)(A) and 10 CFR 50.73(a)(1) to describe an invalid actuation of a general containment isolation signal affecting more than one system.

"On February 3, 2026, Unit 3 experienced a loss of 'A' reactor protection system (RPS). The 3A RPS motor generator (MG) set was found tripped and coasting down. This condition resulted in a half-scram on channel 'A' as well as primary containment isolation system (PCIS) group 2, 3, 6, and 8 isolations. RPS 'A' was placed on alternate in accordance with 3-AOI-99-1. All systems responded as expected.

"Plant conditions which initiate PCIS group 2 and 8 actuations are reactor vessel low water level and high drywell pressure. Plant conditions which initiate PCIS group 3 actuations are reactor vessel low water level and reactor water cleanup area high temperature. Plant conditions which initiate PCIS group 6 actuations are reactor vessel low water level, high drywell pressure, or reactor building ventilation exhaust high radiation (reactor zone or refuel zone). At the time of the event, these conditions did not exist; therefore, the actuation of the PCIS was invalid.

"Upon investigation, a conductor was found broken inside the crimp of a ring lug, most likely due to overtightening and high cyclic fatigue. The lug was on the conductor between the contacts of the thermal overload relays. This opened the circuit to the 1K relay, and the motor starter, which was the cause of the loss of the MG set. The lug was repaired, the condition was cleared, and all systems were realigned as necessary.

"There were no safety consequences or impact to the health and safety of the public as a result of this event.

"This event was entered into the corrective action program as condition report 2065520.

"The NRC Resident Inspector has been notified of this event."

AGREEMENT STATE REPORT - MEDICAL EVENT

The following information was provided by the PA Bureau of Radiation Protection (the Department) via email:

"On March 31, 2026, the licensee informed the Department of a medical event involving an administration of a dose to the wrong individual. It is reportable as per 10 CFR 35.3045(a)(1)(ii)(c).

"On March 31, 2026, a patient was scheduled to receive Tc-99m sestamibi. The nuclear medicine technologist accidentally administered 1 mCi of I-131 that was intended for another patient. Details are still incoming at this time. The patient and referring physician have been notified. The dose to the patient is currently being calculated. We will provide more information as soon as provided.

"The Department will perform a reactive inspection."

PA event report ID number: PA260005

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.

AGREEMENT STATE REPORT - LOST SOURCE

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

"On February 6, 2026, the Department received a complaint from an individual listing several concerns regarding a licensee. One of the concerns was that the licensee was unable to locate two moisture density gauges. On March 5, 2026, the Department performed an on-site investigation. The investigators found that a new radiation safety officer (RSO) had been hired two weeks prior to the investigators arriving. During the investigation, the investigators found that three gauges could not be accounted for on paper. The RSO stated they were in the middle of an inventory, and they would finish it that day and let us know what they found. Later that night, the RSO contacted the Department and stated they had located two of the gauges. They provided transfer papers showing a gauge had been transferred to another licensee. They also provided pictures of [another] gauge not previously found. The RSO stated that the records that were kept by the previous RSO were in disarray and would take some time to look through, but he was sure they would locate the gauge.

"On April 1, 2026, the RSO contacted the Department and stated they had reviewed all the paperwork they could find and did not find any document that would provide the location of the third gauge; therefore, they considered the gauge lost. The RSO reported that the gauge was last documented in their possession in March 2025.

"The gauge is a Troxler model 3430 containing 40 millicuries of Am-241 and 8 millicuries Cs-137. The RSO stated they did not believe the device is an exposure risk to any individual.

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

Texas NMED number: TX260006

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 MEDICAL SOURCE

The following information was provided by the Florida Bureau of Radiation Control via email:

"On April 1, 2026, at approximately 1315 EDT, a radioactive medical source was identified as missing from Moffitt Cancer Center in Tampa, Florida. It was discovered that the drug Lutathera, which is a lutetium-177 (Lu-177) medical unsealed source used for intravenous therapy, had been accidentally discarded on March 31, 2026, at approximately 1600 EDT by a nuclear medicine technician. At the time of disposal, the activity was approximately 221 millicuries (mCi), and it was scheduled for patient administration on April 1, 2026, at an activity of approximately 202 mCi. The source has a half-life of 6.65 days. The source was fully sealed in its original packaging in a lead pig. Trash collection had already taken place before the source had been reported missing. The source is believed to have been transported to a landfill. Due to the sealed packaging and shielding, the risk of environmental contamination or public exposure is considered low. The source is expected to decay in the landfill because of its short physical half-life."

Florida incident number: FL26-029

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