Event Notification Report for July 11, 2024

EN Revision Imported Date: 7/11/2024

EN Revision Text: MEDICAL EVENT - Y-90 OVERDOSE

The following information was provided by the licensee via telephone:

A patient had a written directive to receive 90 Gy of Y-90 TheraSpheres to the liver. When the order was entered into the system, the wrong activity was entered. The higher activity of 360 Gy Y-90 TheraSpheres was then administered to the patient. The calculated dose to the liver may exceed 50 rem.

The patient and referring physician were informed. No health effect or permanent functional damage is expected.

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.

* * * UPDATE ON 7/9/24 AT 1644 EDT FROM JAMIE EISENBERG TO KAREN COTTON * * *

The following summary was provided by the licensee via telephone:

After further assessment of the event, it was discovered that the patient also received an unintended dose of 360 Gy Y-90 TheraSpheres to the lungs. No health effect or permanent functional damage is expected.

Notified R3DO (Nguyen), NMSS Events Notification (email), NMSS Regional Coordinator (Sun)

* * * UPDATE ON 7/10/24 AT 1250 EDT FROM JAMIE EISENBERG TO ERIC SIMPSON * * *

The following information was provided by the licensee via telephone and email as a clarification to the July 9, 2024, update:

"The patient's Y-90 TheraSphere treatment resulted in an unintended dose to an organ/tissue other than the treatment site. The estimated intended dose was 0.9 Gy to the lungs. The estimated dose given the lungs was 3.29 Gy. The estimated overage was 2.39 Gy, which is 165 percent over the intended lung dose.

"This administration occurred on May 6, 2024, and was the second administration of the patient's regime. The previous treatment was on April 16, 2024, and was completed as intended. The patient's cumulative lung dose from both treatments was 4.2 Gy. The planned lung dose for the regime was 1.8 Gy, again showing the approximately 2.4 Gy overage from the May 6, 2024, administration."

Notified R3DO (Nguyen), NMSS Events Notification (email), and NMSS Regional Coordinator (Sun)

DAMAGED DENSITY GAUGE

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

At 1146 CDT on 7/3/2024, the radiation safety officer at Midwest Subsurface Testing reported a gauge was damaged on a construction site. An InstroTek MC1 Elite moisture density gauge containing 10 millicuries of cesium-137 and 50 millicuries of americium-241/beryllium was backed over by a skid loader. The source was stuck in the shielded position. A radiological survey was conducted, which verified there was no contamination. The damaged gauge was recovered and transported to a vendor facility to conduct a leak test.

This event was reported under 10 CFR 30.50 (b)(2).

AGREEMENT STATE REPORT - LOST GAUGE

The following information was provided by the Utah Division of Radiation Control (the Department) via email:

"On July 3, 2024, a technician for American Testing Services, Inc. (ATS), completed a job at a temporary jobsite. They placed the gauge on the tailgate while they completed the paperwork. Then, they left the jobsite but failed to put the gauge in the transportation box and secure the gauge for transport. Reportedly, the gauge was in the shielded position when on the tailgate. It is unknown if was locked in the safe position or not.

"The technician drove away from the site and made a stop down the road. When they left that location, they noticed that the gauge and the transportation case were no longer on the vehicle, but the chains were still on the truck. They retraced the route but did not find the gauge. Afterwards, the technician reported the gauge missing to the radiation safety officer (RSO).

"The RSO reported the incident to the Department. The only information given at that time was that a gauge was lost. There was no information regarding where the incident occurred, what isotopes and activity were involved, information regarding what happened, etc. The RSO was informed to get more information regarding the details for the incident and provide the information to the Department as soon as possible."

Utah Event Report ID number: UT240005

AGREEMENT STATE REPORT - PATIENT UNDERDOSE

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

"On July 3, 2024, the licensee informed the Department of a medical event involving a treatment with SirSpheres [Y-90 resin microspheres].

"A patient was about to undergo a treatment with SirSpheres when the physician noticed a globule on the vial septum. They cleared the globule and began the treatment. At the beginning of treatment, the tube became occluded immediately, resulting in the patient receiving only 0.2% of the prescribed dose. The procedure was stopped. The physician and patient have been informed. No harm to the patient is expected from this event."

PA Event Report ID: PA240014

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.

MANUAL REACTOR TRIP AND AUTOMATIC SAFEGUARDS ACTUATION

The following information was provided by the licensee via email:

"At 2125 EDT on 07/08/2024, with Unit 3 in Mode 1 at 100 percent power, the reactor was manually tripped due to main feedwater pump `A' miniflow valve failing open, which resulted in lowering steam generator water level. Additionally, an automatic safeguards actuation occurred due to the cooldown of the reactor coolant system. The trip was not complex, with all safety systems responding normally post-trip.

"Operations responded and stabilized the plant. Decay heat is being removed by the passive residual heat removal heat exchanger. Units 1, 2, and 4 are not affected.

"Due to the core makeup tank actuation, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(A). The reactor protection system actuation while critical is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B). Additionally, this event is reportable per 10 CFR 50.72(b)(3)(iv)(A) as an event that resulted in a valid containment isolation actuation and a valid passive residual heat removal heat exchanger actuation.

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

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

The cause of the main feedwater pump 'A' miniflow valve failing open was unknown and under investigation at the time of the notification of this event to the NRC.

LOSS OF COMMUNICATIONS CAPABILITIES

The following information was provided by the licensee via email:

"On July 09, 2024, at 0455 CDT the National Weather Service reported to Cooper Nuclear Station that the National Warning System radio tower near Shubert, Nebraska was not working. The Shubert Tower transmitter activates the Emergency Alert System/Tone Alert Radios used for public notification. Additional information from the National Weather Service received July 10, 2024, at 0455 CDT determined that the Shubert Tower transmitter was not able to be repaired within 24 hours and is still non-functional. A backup notification system has been verified to be available during this period.

"This is considered to be a major loss of the Public Prompt Notification System capability. Due to the unplanned loss of the primary notification system for greater than 24 hours, this condition is reportable under 10CFR50.72(b)(3)(xiii), since the backup alerting methods do not meet the primary system design objective. A backup notification system is available to use for notifications if needed.

"The NRC Senior Resident Inspector has been informed."

EN Revision Imported Date: 7/11/2024

EN Revision Text: AUTOMATIC REACTOR SCRAM DUE TO MANUAL TURBINE TRIP

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

"At 0728 EDT on July 10, 2024, with Unit 2 in Mode 1 at 24 percent power, the reactor automatically scrammed due to a manual turbine trip. The [reactor] scram was not complex with all systems responding normally. Reactor vessel level reached the low-level set-point following the scram, resulting in valid Group 2 and Group 3 containment isolation signals. Due to the reactor protection system actuation while critical, this event is being reported as a four hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B) and an eight hour, non-emergency notification per 10 CFR 50.72(b)(3)(iv)(A) for the Group 2 and Group 3 isolations.

"Operations responded using emergency operating procedures and stabilized the plant in Mode 3. Decay heat is being removed by discharging steam to the main condenser using the turbine bypass valves. Unit 3 was not affected.

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