Event Notification Report for March 25, 2026

AGREEMENT STATE REPORT - LOST I-125 SEED

The following information was received from the Massachusetts Radiation Control Program (the Agency) via email:

"On March 11, 2026, one radioactive iodine-125 sealed source (seed) was removed from a patient receiving a radioactive seed localization procedure. The licensee expected to remove two iodine-125 seeds, which were placed in the patient on March 10, 2026, but only located one of the seeds. The activity of the missing seed is 0.167 mCi. The missing seed manufacturer is IsoAid, LLC. The model number of the seed is IAI-125A.

"The missing seed was not located after extensive surveys of the patient, patient's car and home, staff, and all areas where the seed may have been misplaced. The seed has not been located at this time.

"The reporting requirement is within 30 days and is 105 Code of Massachusetts Regulations (CMR) 120.281(A)(2), missing licensed radioactive materials in aggregate quantity equal to or greater than 10 times quantity specified in 105 CMR 120.297, Appendix C.

"The Agency considers this event to be open."

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 - MEDICAL EVENT

The following information was provided by the Illinois Emergency Management Agency (the Agency) via phone and email:

"The Agency was contacted by a consultant for Methodist Medical Center of Illinois to report that a patient, treated with Y-90 Theraspheres to the right hepatic lobe last month, was scheduled for a Y-90 Theraspheres treatment to the left hepatic lobe on Friday, March 13, 2026. Angiographic images taken just prior to the Y-90 administration confirmed the proper placement of the microcatheter tip to the 2 left hepatic arterial branches; however, after the treatment, single photon emission computed tomography (SPECT)/computed tomography (CT) imaging only showed activity in the right hepatic lobe.

"The authorized user (AU) reported that the catheter tip must have prolapsed into the adjacent right hepatic artery during administration, causing the activity to go to the right hepatic lobe again. No untoward effects are expected to the patient since the dose was distributed within the right hepatic lobe in a similar distribution pattern (into the hepatic metastases) at the previous post treatment scan with the exposure predominantly at the site of the disease. The AU performing the treatment wants the patient to get a Cu-64 dotatate scan in 4 weeks to evaluate whether there has been a favorable response achieved in the right lobe from the Y-90 and then schedule the patient for a Y-90 treatment to the left hepatic lobe. At this time, the licensee has confirmed that the patient was notified but is still gathering information regarding notification of the referring physician.

"This matter is reportable under 32 Illinois Administrative Code 335.1080(a)(1)(C) no later than the next calendar day after discovery of the medical event. Reporting requirements were not met by the licensee and will be addressed through forthcoming inspection correspondence.

"A reactive inspection will be conducted next week to interview staff, review documents and images, and gather information as to root cause and proposed corrective actions."

Illinois Item Number: IL260008

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 - MEDICAL EVENT

The following is a summary of information provided by the Radiation Health Branch (RHB) of the Kentucky Department for Public Health and Safety via email:

RHB reported that the licensee had an incorrect tagging agent for some Cardiolite [Tc-99m] doses and several patients were affected. Patients were injected, but the isotope didn't go where intended for imaging. The patients were re-dosed with the properly tagged isotope.

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 I-125 SEED

The following information was received from the Virginia Radioactive Materials Program (VRMP) via email:

"On February 17, 2026, the licensee discovered and reported a lost I-125 [radioactive seed localization (RSL)] seed with an activity of 0.1186 mCi that was placed in a patient on February 16, 2026. Two seeds were implanted on February 16, 2026, and only one seed was found in surgery on February 17, 2026. A thorough search, including an extensive survey, was performed by the licensee, but the seed was not located.

"The seed meets the reporting requirement of 30 days from discovery.

"The licensee provided a report that included an acceptable root cause analysis and corrective action plan on February 26, 2026. The licensee determined the cause to be an inadequate procedure for implant/removal of RSL seeds and will revise their implant/removal procedure to better locate and account for all seeds placed."

Virginia event report number: VA260002

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 - DAMAGED TROXLER GAUGE

The following information was provided by the Utah Department of Environmental Quality, Division of Waste Management and Radiation Control (the Division) via email:

"During a routine inspection on March 17, 2026, the inspectors identified an incident that occurred on approximately June 20, 2025, that was not reported to the Division. The licensee performed work at a temporary jobsite using a Troxler moisture density gauge (model: 3440P, serial number: 89320, isotope: Am-241:Be/40 mCi, Cs-137/9 mCi). The gauge operator was loading the bed of his truck and left the gauge sitting on the ground and a recreational vehicle (four-wheeler) ran over the gauge. The sources were in a safe, shielded position and were not exposed at the time the gauge was run over. Although the damage to the gauge was minor, the gauge exposure handle was bent which prevented the licensee from exposing the source rod. The licensee plans to send the gauge to the manufacturer for repair or disposal.

"Additional information will be provided in the NMED submittal."

Utah event report ID number: UT 260004

DEGRADED CONDITION

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

"On March 21, 2026, at approximately 0945 EDT, with Unit 2 in mode 4 during a planned refueling outage, personnel discovered boric acid on the mirror insulation on top of the `2B' reactor coolant system (RCS) crossover leg piping. On March 24, 2026, at 1747 EDT, it was identified to be a through-wall flaw on a three-quarter inch instrument line. The leakage is minor in nature and unquantifiable. The leakage is coming from a welded connection upstream of a low pressure flow transmitter root-valve connecting to the `2B' RCS crossover elbow.

"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."