Event Notification Report for October 07, 2026

AGREEMENT STATE REPORT - STUCK SHUTTER

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

"On September 30, 2026, the Department was contacted by the licensee to report a radiation event that had been identified at 0145 CDT. The licensee was performing routine work utilizing a fixed gauge device when the device operator received an alert from the control panel that a shutter was unable to close. A process engineer and the radiation safety officer were immediately notified and came onsite. The area was cordoned off to ensure no employees entered the area while the shutter was open. At approximately 0500 CDT, the shutter was able to be closed after cycling the system a few times. The gauge appears to be functioning as intended again.

"The device is a Mahlo Model 11-200933. It contains an Eckert and Ziegler Kr-85 KAC.93 source, SN: AG-4785. It has an assay date of March 29, 2016, at 260 mCi. It currently contains approximately 132 mCi.

"No employees were exposed to any elevated radiation levels. The manufacturer was notified and is currently coordinating with the licensee to get a service engineer on site. The Department will continue to follow up with the licensee."

Wisconsin incident number: WI260016

AGREEMENT STATE REPORT - LOST SOURCES

The following is a summary of information provided by the Illinois Emergency Management Agency (the Agency) via email:

On September 29, 2026, the radiation safety officer (RSO) at Northwestern Memorial HealthCare (the licensee), contacted the Agency to advise of a missing package containing two Ge-68 PET camera sealed sources (0.067 mCi and 0.402 mCi as of the date of shipment). The package was shipped to Eckert & Ziegler on August 26, 2026 via common carrier. On September 29, 2026, the RSO contacted Eckert & Ziegler to request a returned source acknowledgment letter and Eckert & Ziegler confirmed that they had not received the shipment. The licensee contacted the common carrier, and they were unable to locate the package. This report will be updated as additional information becomes available.

Illinois item number: IL260027

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

PART 21 - NON-COMPLIANT TRIP LATCH ASSEMBLY

The following is a summary of information provided by ABB Inc by email and phone:

On July 29, 2026, ABB was notified by Duke of a potential deviation associated with a trip latch assembly, part number 196951K01 (catalog identification number 318334), supplied under PO 03214575. During refurbishment of a QA-1 ABB 5HK350 2000A breaker, the breaker would not remain closed after installation of the new trip latch assembly and tripped open each time it was closed. Following reinstallation of the original trip latch assembly, the breaker operated as expected.

Duke Energy compared the new trip latch assembly to the previously installed assembly and identified that latch arms appeared to be welded in different positions. When placed on a flat surface, the top of the arm on the previously installed assembly measured approximately 2 inches, while the top of the arm on the new assembly measured approximately 2-1/4 inches. Two of the eleven assemblies received exhibited the gap. None of the eleven assemblies were installed in the plant.

ABB Engineering evaluated the affected assemblies and determined that the supplied parts did not conform to applicable design drawing requirements. Specifically, certain dimensions associated with the latch arm geometry were outside the specified design requirements.

ABB is replacing the potentially affected trip latch assemblies for the customer. In addition, ABB has implemented corrective actions including enhanced engineering review of dimensional requirements, revised manufacturing controls and additional inspection and verification steps to prevent recurrence of this condition.

Affected Plant: Oconee Nuclear plant.

Responsible ABB Inc. representative:
Percy Isaac
Plant Manager
ABB Inc.
2300 Mechanicsville RD
Florence, SC 29501
843-413-4700