Event Notification Report for March 23, 2026

AGREEMENT STATE REPORT - STUCK SHUTTER

The following report was received via email by the Tennessee Division of Radiation Health:

"During a scheduled 6-month shutter check, it was discovered that a gauge shutter was stuck in the open position. No abnormal levels of radiation were detected, and the position was consistent with normal operation. A VEGA field technician has been contacted to service the gauge.

Manufacturer: Ohmart/Vega
Source Holder Model: SHF2
Source SN: 64793
Isotope: Cs-137, 92.2 mCi (adjusted for decay)

"Corrective actions, reports, and any additional information will be provided in an NMED report within 30 days."

Tennessee Report ID number: TN-26-016

AGREEMENT STATE REPORT - FAILED AFTERLOADER DEVICE

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

"The Agency was contacted [on March 13, 2026,] by the radiation safety officer for OSF Healthcare System (doing business as St. Francis Medical Center) in Peoria, Illinois to report an equipment failure on a Bravos high dose rate (HDR) afterloader device. The failure involved a data communication error between the console and the HDR unit. This was discovered prior to use on patients and, according to the licensee, did not result in any administrations deviating from the written directive. Regardless, this matter is reportable under 32 Illinois Administrative Code 340.1220(c)(2) within 24 hours. Inspectors will be on site to gather necessary information on Tuesday, March 17.

"The licensee advised the manufacturer is already on site correcting the issue and identifying root cause. This report will be updated when additional data becomes available."

Illinois Event Number: IL260007

MEDICAL EVENT

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

The licensee reported a procedural error involving a written directive for an I-131 sodium iodide therapeutic administration, in potential violation of 10 CFR 35.41.

A patient presented to the facility on February 23, 2026, for a prescribed 29 mCi I-131 therapy. Prior to administration, the patient informed the supervising authorized user (AU) that they would be leaving the country for three days following the scheduled treatment. The AU and the radiation safety officer (RSO) determined that it would be more appropriate to delay the administration until the patient returned. The therapy was therefore not administered on that date.

The patient returned on March 11, 2026, for the rescheduled therapy. The originally assigned AU was unavailable. Another physician, who is board-certified and had prior residency training in nuclear medicine but is not listed on the license as an AU, was present during the administration. The technologist administered the therapy under this physician's observation.

Because the observing physician was not listed as an AU, they could not sign the written directive. The technologist believed the original AU could sign the required section upon returning, not recognizing this was not compliant with 10 CFR 35.41. The RSO was notified of the issue on March 13, 2026, at approximately 1400 CDT.

The referring physician was notified on March 13, 2026. The referring physician requested that the patient not be notified, stating that the situation did not affect the clinical outcome of the treatment. The licensee reported the event to the NRC Operations Center on March 13, 2026, within 24 hours of identifying the error.

The licensee has stated that a corrective action report will be submitted within 15 days.

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.

* * * RETRACTION ON 03/16/2026 AT 0912 EDT FROM NICHOLAS BELL TO ADAM KOZIOL * * *

The licensee is retracting this event after discussing the details with the NRC Inspector.

Notified R3DO (Edwards), NMSS Events (email)

INVALID SYSTEM ACTUATION

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

"This 60-day telephone notification is being made in lieu of a licensee event report (LER) in accordance with 10 CFR 50.73(a)(1) for an invalid actuation of the emergency service water (ESW) system reportable under 10 CFR 50.73(a)(2)(iv)(A) at the Prairie Island Nuclear Generating Plant Units 1 and 2.

"At 1343 CST on January 26, 2026, during post maintenance testing associated with the time delay relay replacement work for the 22 diesel driven cooling water pump (DDCLP), an ESW pump on `B' train, a jumper was installed to test an annunciator. The jumper bypassed part of the normal start circuitry and allowed a spurious start signal. As a result, the 22 DDCLP automatically started without operator command. At the time of the start, the pump was inoperable and return-to-service testing had not been completed; certain isolations, including DC control power, had been restored, which made the unintended actuation possible.

"This event is considered an invalid system actuation of the ESW system. The actuation was not initiated in response to actual plant conditions or parameters. The 22 DDCLP started and functioned as expected in response to the start signal.

"The NRC Resident Inspector has been notified."

UNUSUAL EVENT DECLARED FOR RCS LEAKAGE FOR GREATER THAN 15 MINUTES

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

At 0819 MST on 3/19/2026, with Palo Verde Unit 2 at 95 percent power, the site declared an Unusual Event under emergency action level 'SU5.1' due to identified reactor coolant system leakage for greater than 15 minutes. The leak was isolated by securing letdown. A manual reactor trip was inserted, and Unit 2 is currently shutdown in mode 3. Palo Verde Units 1 and 3 were unaffected.

State and local authorities were notified.

The NRC Senior Resident Inspector has been notified.

Notified DHS SWO, FEMA Ops Center, FEMA NWC, CISA Central, CWMD Watch Desk, DHS Nuclear SSA (email), and DHS NRCC THD Desk (email).


* * * UPDATE ON 03/19/2026 AT 1535 EDT FROM PEDRO REGUERA TO BETHANY CECERE * * *

The following update was provided by the licensee via phone:

This update is a 10 CFR 50.72(b)(2)(iv)(B) required report of a valid RPS actuation while critical due to operators tripping Palo Verde Unit 2 at 0841 MST.

Notified R4DO (Dixon), NRR EO (Feliz Adorno), IR MOC (Whited), R4RA (Monninger), NRR (Groom), R4 PAO (Smith), and NSIR (Williams).


* * * UPDATE ON 03/19/2026 AT 1717 EDT FROM COLLIN MILLER TO JOSUE RAMIREZ * * *

The following information was provided by the licensee via phone:

Palo Verde Unit 2 terminated the notice of unusual event 'SU5.1' at 1410 MST. The leak was isolated, the plant is stable, and there was no release.

State and local authorities were notified.

The NRC Senior Resident Inspector has been notified.

Internal notifications: R4DO (Dixon), NRR EO (Feliz Adorno), IR MOC (Whited), R4RA (Monninger), NRR (Groom), R4 PAO (Smith), and NSIR (Williams).

External notifications: DHS SWO, FEMA Ops Center, FEMA NWC, CISA Central, CWMD Watch Desk, DHS Nuclear SSA (email), and DHS NRCC THD Desk (email).

AGREEMENT STATE REPORT - MEDICAL EVENT

The following information was provided by the Arizona Department of Health Services (the Department) via email:

"On March 13, 2026, the Department was notified that a medical event involving Y-90 Sirtex SIR-Spheres had occurred at St. Joseph's Hospital on March 12, 2026. During administration, staff noticed there was leakage from the tubing connecting the delivery system to the patient indicating an improperly secured connection. The procedure was immediately paused to assess the leak, the catheter was re-attached, and the administration continued. Preliminary dose assessment indicated that approximately 58 percent of the intended activity was delivered to the patient. The Department continues to investigate the event.

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

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 - OVEREXPOSURE

The following information was received from the New York State Department of Health, Bureau of Environmental Radiation Protection (the Department) via email:

"On 03/02/2026, a report was sent to the Department regarding an occupational overexposure. The report indicates that an individual received 5.151 rem total effective dose equivalent for the year 2025. This exceeds occupational dose limits specified in 10 CFR 20.1201(a)(1)(i) and must be reported per 10 CFR 20.2203(a)(2)(i) within 30 days after learning of the occurrence. The licensee became aware of the overexposure during review of dosimetry records on 02/19/2026 and submitted their report to the Department within 30 days, as required.

"The licensee is a mobile imaging service provider based in a non-Agreement State [South Dakota] and the individual exceeding the occupational dose for the year 2025 was a traveling nuclear medicine technologist (NMT). The exposure is believed to have occurred due to work procedures and air travel. The individual had taken 42 one-way work flights in 2025 and indicated that he had left the badge in carry-on luggage an unspecified number of times. The individual was informed that they should not be putting their badge through the Transportation Security Administration (TSA) scanner. The report also details that the individual was found to be using poor dose handling techniques during positron emission tomography (PET) scans which led to higher-than-expected doses. The individual was informed that they should review their work procedures for possible reduction of exposure and to apply the rules of time, distance, and shielding to keep exposures as low as reasonably achievable (ALARA). These communications were made by the radiation safety officer (RSO) to the individual in ALARA 1 notifications and other meetings throughout 2025.

"In December of 2025, it was discovered that the individual had lost their December badge and could not recall the date. The licensee provided the individual with a spare badge and using a calculation of an average of the previous 3 months, assigned 775 mrem to their body badge.

"The corrective actions for this incident included retraining the individual, resending radiation safety policies and procedures to the individual, and a personalized ALARA improvement plan which was implemented to correct behaviors, work practices, and planning deficiencies to reduce the employee's radiation exposure. The individual's dosimetry records will also promptly be reviewed and any quarterly dose exceeding 1250 mrem will result in stopping all work in radiation areas for a period to reduce employee exposures below the required limits.

"This incident is being tracked under Incident No. 1556. The corrective actions have been deemed acceptable to the Department and this incident has been closed."

NY Event Report ID: NY-26-03
NY Incident Number: 1556