Event Notification Report for October 19, 2026

EN Revision Imported Date: 10/19/2026

EN Revision Text: INTERIM PART 21 REPORT - VALVE ASSEMBLY MOTOR FAILURE

The following is a summary of information provided by ABB Motors and Mechanical (ABB) via phone and email:

Potential defects were identified in safety-related motors supplied via Flowserve. Flowserve and ABB were informed that during commissioning of a new SBD-3 actuator and valve assembly, the actuator motor failed to operate. A summary of a third-party failure analysis provided by Bruce Power indicated that the likely cause of the failure was attributable to mechanical interference between a rotor balance weight and the stator winding causing insulation damage and turn-to-turn short. To date, the subject motor has not been returned to ABB for inspection.

Affected Plants: Unknown

Component Information:
Component Type: Safety-related AC electric motors for motor-operated valve (MOV) applications.
Motor Serial Number: GG215020118 supplied to Flowserve Corp.- Limitorque Actuation.
Motor Identifier: Flowserve part# R-403-F03-080000A20
Description: 100 ft-lb, 3/60/575, 2-pole motor

Contact Information:
Sam Bosworth
ABB Motors and Mechanical Inc.
Interim Quality Manager
Office: (678) 947-7274
Email: sam.bosworth@us.abb.com
Address: 4349 Avery Drive, Flowery Branch, GA, 30542

* * * UPDATE ON 07/31/2026 AT 1705 EDT FROM SAM BOSWORTH TO KAREN COTTON * * *

The following information was provided by ABB via email:

"ABB continues to perform an extent of condition analysis to identify motor designs which could potentially be affected. Subsequently, a review of available borescope inspections of the motor lot size procured on this specific order was completed eliminating motors which could be visually verified to have no weights added to the rotor during the balancing process. As an engineering enhancement of the motor design, balance weights have been eliminated. Work instructions have been revised accordingly. Inspection checks have also been implemented to verify no balance weights have been used.

"ABB has identified seven motors at risk using several parameters including but not limited to ship date and inspection records. The list of motors below, identified by serial number, is being shared with our customer Flowserve for assistance identifying the location and end user of the motor. This information will be provided when available. It should be noted that if a motor has been in service and operating without issue there is minimal risk for this condition. ABB recommends performing a megger test on the following serial numbers which can be found on the motor nameplate. If utility has a defined preventative maintenance program for insulation resistance follow that protocol.

"Testing Guidance:
 Compare new megohm readings to historical baseline data
 Consistent readings confirm motor integrity
 For motors without baseline data: acceptable minimum is 5 megaohms (new condition)
 Results at or above baseline = Motor can be cleared from this nonconformance

"List of Motors
GG215120026
GG201320128
GG194420114
GG194020217
GG184220163
89160683-010-002
81199658-010-001

"This is the second Interim notification. Per the requirements of 10 CFR 21.21(d) a follow-up notification of evaluation status will be submitted on or before August 14, 2026."

Notified R1DO (Haney), Part 21 Reactors (email).

* * * UPDATE ON 08/14/2026 AT 1508 EDT FROM SAM BOSWORTH TO PHILIP ALIER * * *

The following information was provided by ABB via phone and email:

The extent of condition determination revealed that 150 ft-lb 2-pole, aluminum rotor construction motors could be affected, which have been evaluated accordingly.

This is the final notification report.

Notified R1 Reactor Events and Part 21 Reactors via email.

* * * UPDATE ON 10/16/2026 AT 1739 EDT FROM SAM BOSWORTH TO BRIAN P. SMITH * * *

The following information was provided by ABB via email:

At the request of the end user, the final report was amended to add the suffix -C to Motor Serial Numbers B1199658-010-1 and B9160683-010-2 on the table on page 3.

This is an amended final notification report.

Notified R1 Reactor Events and Part 21 Reactors via email.

AGREEMENT STATE REPORT - LOST EXIT SIGN

The following is a summary of information provided by the Colorado Department of Public Health and Environment via email:

Two exit signs, each containing 7.5 curies of tritium (15 curies total), were determined to be lost by the licensee.

Manufacturer: Isolite Corporation
Model Number: SLX60

Colorado Event Report ID Number: CO260024

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

RCS PRESSURE BOUNDARY DEGRADED

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

"At 1305 EDT on October 15, 2026, it was determined that the reactor coolant system (RCS) pressure boundary did not meet the acceptance criteria under ASME, Section XI IWB-3514, 'Standards for Examination Category B-F, Pressure-Retaining Dissimilar Metal Welds in Vessel Nozzles, and Examination Category B-J, Pressure-Retaining Welds in Piping.' The condition will be resolved prior to plant startup. This event is being reported as an eight-hour non-emergency notification per 10 CFR 50.72(b)(3)(ii)(A).

"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 condition was discovered during ultrasonic testing (UT). The flaw is located between the pressurizer and the "A" pressurizer safety valve at a pipe elbow.

AGREEMENT STATE REPORT - DAMAGED MOISTURE DENSITY GAUGE

The following is a summary of information provided by the Louisiana Department of Environmental Quality (LDEQ) via email:

On October 10, 2026, a Troxler model 3400 gauge, with an 8 mCi Cs-137 source and a 100 mCi Am-241/Be source, was being checked for stabilization before leaving the licensee's facility when it was backed over by a vehicle. The equipment housing was crushed, but the sources were still in a shielded condition. The device was placed into the yellow transport container.

LDEQ and the licensee both dispatched personnel to survey the gauge. Surveys confirmed that the sources were still in a shielded position and no radiation exposures to workers had occurred.

The licensee reported the event to LDEQ on October 12. The licensee will perform leak tests of the sources.

Louisiana event number: LA20260012

AUTOMATIC REACTOR TRIP

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

"On October 16, 2026, at 2245 CDT, Waterford 3 Steam Electric Station Unit 3 was operating at 75 percent power. While reducing power in preparation for a refueling outage, an automatic reactor trip was initiated due to an automatic turbine trip. Fast dead bus transfer of the '2B' bus failed resulting in emergency diesel generator 'B' (EDG B) starting and loading on to the '3B' bus.

"An emergency feedwater (EFW) actuation signal (EFAS) was received, and EDG B automatically started. The unit is currently stable in mode 3. All control rods fully inserted as expected. Decay heat removal is through the main condenser.

"This event is being reported as a 4-hour non-emergency notification in accordance with 10 CFR 50.75(b)(2)(iv)(B) as an actuation of the reactor protection system (RPS) when the reactor is critical and as an 8-hour non-emergency notification in accordance with 10 CFR 50.72(b)(3)(iv)(A) as a valid actuation of the EFW system and the EDG.

"The NRC Resident Inspector has been notified."

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

At the time of the turbine trip, routine testing of the turbine electrohydraulic system was in progress, but the cause of the turbine trip in being investigated.