Event Notification Report for April 17, 2023

AGREEMENT STATE REPORT - POSSIBLE OVEREXPOSURE DOSE FOR AN EMBRYO/FETUS OF A DECLARED PREGNANT WOMAN

The following was received from the South Carolina Department of Health and Environmental Control (the Department) via email:

"On 03/24/23, at 1446 [EDT], the Department was notified by the licensee of a dose more than the dose limit for an embryo/fetus of a declared pregnant woman. A written report was also submitted on 03/24/23. The employee is a Technical Assistant for mobile [positron emission tomography/computed tomography] (PET/CT) operations and is not directly involved with handling radioactive material. The estimated dose reported was 1145 mrem [deep dose equivalent] (DDE) for a one-month period, the cumulative dose was 1239 mrem DDE. The licensee's report indicated it is possible that the badge may have been in the PET/CT scanner room during patient scans, but the employee could not recall that this ever happened. The licensee also reported the chest and control badges showed no elevated readings; only the fetal badge. The licensee's corrective actions included discussing with the employee the importance of making sure the badge is never left in a radiation area, and while at work, the badge is always worn properly for the entire day. Proper storage of badges next to the control badge was also discussed. The Department performed an on-site investigation on 03/29/23, and the information obtained during the on-site investigation was consistent with the licensee's written report. This event is considered closed."

South Carolina Department of Health and Environmental Control report no.: SC230008

AGREEMENT STATE - DAMAGED RADIOGRAPHY GUIDE TUBE PREVENTING RETRACTION OF SOURCE

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

"On April 10, 2023, the licensee reported to the Agency that on April 7, 2023, one of its QSA Delta 880 industrial radiography exposure devices (camera) had fallen approximately three feet onto the source guide tube at a job site in Orla, Texas. The camera severed the guide tube and the source pigtail was disconnected from the drive cable. The source was 72 curies of iridium-192. A boundary was set at 2 millirem by the radiographers and an individual authorized on their license was dispatched to the site and retrieved the source. The retriever's dosimeter indicated a whole-body dose of 2.6 rem. The licensee has reported initial calculations for the retriever's hand dose to be 385.9 millirem. The two radiographer's self-reading pocket dosimeters indicated doses of 180 and 150 millirem. All of the equipment is being sent to the manufacturer for evaluation. An investigation into this event is ongoing. More information will be provided as it is obtained in accordance with SA-300."

Texas Incident Number: I-10007

PART 21 - SCHNEIDER ELECTRIC POWER SUPPLY HARD FAILURES

The following information was provided by the licensee via email:

"On September 7, 2022, Dominion's Surry Power Station notified United Controls International (UCI) that three Schneider Electric PIN: ASP840-000 Modicon Primary/Secondary Power Supply units that were supplied by UCI in 2014 had failed after installation. Hard failures that shutdown the associated programmable logic controller were observed. The first unit was installed since June 6, 2017, and then failed in August of 2022. The second and third units failed approximately three days after installation. All units appeared to function properly at initial installation.

"The subject items were returned to UCI on October 19, 2022, for evaluation. Items were received at UCI with substantial shipping damage noted. One item was received with a loose transformer inside the unit. All items were received with bent or cracked cases. These issues are attributed to poor shipping practices as items were not supplied in such conditions and these issues would have been noted at receipt by the utility. Due to the complexity of the items and unavailability of design documentation for these obsolete items, further evaluation of item failures required manufacturer (Schneider Electric) evaluation. UCI returned all three items to the manufacturer for evaluation of failed components. The manufacturer was able to repair one item by replacing several capacitors, transistors, integrated circuits, and resistors; however, a specific cause of the failure could not be identified. The remaining two items were determined to be unrepairable, and cause of failure could not be identified.

"UCI is not capable of providing any further evaluation as to the root cause of the subject module failures. The item manufacturer Schneider Electric was also unable to provide a determination as to the cause of failure. Since the root cause of failure cannot be determined or inspected for, UCI will no longer be supplying these modules which are now obsolete."

North Anna and Surry Power Station are the plants affected.