Event Notification Report for October 21, 2026

EN Revision Imported Date: 10/21/2026

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
B9160683-010-002
B1199658-010-001

"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.

* * * UPDATE ON 10/20/2026 AT 1715 EDT FROM SAM BOSWORTH TO ROBERT THOMPSON * * *

The following information was provided by ABB via email:

The last two unit serial numbers in the original report should be:

B9160683-010-2-CT
B1199658-010-1-CT

Palo Verde is the only US unit affected.

Notified (email) R4 Reactor Events, Part 21 and 50.55 Reactors.

AGREEMENT STATE REPORT - LOST SOURCE

The following is a summary of information provided by the Alabama Office of Radiation Control via phone and email:

On October 13, 2026, at approximately 0930 CDT, the radiation safety officer (RSO) for the licensee called to report a lost source in transit. A radiography camera containing a 7.7 Ci Ir-192 source was shipped by common carrier on September 29, 2026, to QSA Global in Texas for routine source exchange, with an arrival date of no later than October 2, 2026.

When the package failed to arrive by October 2, 2026, the RSO notified the common carrier, who informed the RSO that the package was found and located at their sorting facility in Memphis, TN. Subsequently, on the morning of October 13, 2026, the licensee received an e-mail notification from the common carrier that the package could not be located in their Tennessee sorting facility. The carrier stated that the sorting facility was the last known location and the package was still believed to be there.

The licensee continues to follow up with the common carrier to determine the location of the lost source.

Alabama Radiation Control will inform the Tennessee Division of Radiological Health of the event.

Camera: QSA Global model D880, S/N D2705
Source: QSA model 424-9, S/N 25977P, source activity estimated as of 10/13/2026

Alabama incident number: 26-017

* * * UPDATE ON 10/15/2026 AT 0824 EDT FROM SEAN WILLIAMS TO ROBERT THOMPSON * * *

The following is a summary of information provided by the Alabama Office of Radiation Control via email:

The Alabama Office of Radiation Control received an update from the State of Tennessee. The common carrier located the package, which had its shipping label torn off. The package is being returned to the licensee's facility in Alabama.

Notified (email) NMSS Events Notification, ILTAB.

THIS MATERIAL EVENT CONTAINS A 'Category 3' LEVEL OF RADIOACTIVE MATERIAL

Category 3 sources, if not safely managed or securely protected, could cause permanent injury to a person who handled them, or were otherwise in contact with them, for some hours. It could possibly - although it is unlikely - be fatal to be close to this amount of unshielded radioactive material for a period of days to weeks. These sources are typically used in practices such as fixed industrial gauges involving high activity sources (for example: level gauges, dredger gauges, conveyor gauges and spinning pipe gauges) and well logging. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf

AGREEMENT STATE REPORT - UNATTENDED PORTABLE GAUGE

The following information was received from the Virginia Radioactive Materials Program (VRMP) via email:

"At approximately 1330 EDT on October 12, 2026, the VRMP was notified of an incident involving a portable nuclear gauge. At approximately 0800 EDT on October 12, 2026, DMY Engineering Consultants was notified by the general site contractor that one of their Troxler model 3440 portable moisture and density gauges (S/N 31062) had been located at a jobsite located at the Hampton Roads Bridge-Tunnel.

"The radiation safety officer (RSO) informed VRMP that the authorized user had returned to the office on October 11, 2026, with the empty gauge case, leaving behind the gauge at the jobsite. The RSO contacted the VRMP by phone within 24 hours. Per the RSO, the gauge was recovered from the jobsite at approximately 0900 EDT on October 12, 2026. It was determined that the gauge was left unattended between approximately 0800 EDT on October 11 and 0900 EDT on October 12. The gauge was undamaged and appeared to be untampered with as it was found in the same place that the gauge user stated he left it. The Cs-137 source (8 mCi, S/N 750-5681) remained in the fully shielded position and the Am-241/Be source (40 mCi, S/N 47-10729) block remained intact. A survey taken by the RSO [showed 0.05 mR/h at 1 meter]. The gauge was secured in its transportation case and returned to the licensee's storage to be leak tested before shipment for evaluation. There were no apparent exposures as a result of this incident. The agency will conduct a formal investigation."

Virginia incident number: VA260006


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

AGREEMENT STATE REPORT - STUCK SHUTTER

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

"On October 13, 2026, the Department was notified by the licensee that the source shutter mechanism on a nuclear gauge had failed to function as designed. The gauge, a Ronan model SA1-F37, contains a 300 mCi Cs-137 sealed source. The licensee reported that the gauge was discovered with the source shutter stuck in the open position. Open is the normal operating position.

"The condition was identified during a visual inspection and shutter check conducted on October 12, 2026. The licensee stated that there is no risk of additional radiation exposure to members of the public or radiation workers as a result of this shutter mechanism failure.

"Additional information will be made available in accordance with SA-300 reporting requirements."

Texas incident number: 10338

AGREEMENT STATE REPORT - MEDICAL EVENT

The following is a summary of information provided by the Oregon Health Authority's Radiation Protection Services (RPS) via phone and email:

On October 13, 2026, RPS was notified by the licensee of activity delivered outside the intended target during a Y-90 microsphere treatment for liver cancer.

The written directive prescribed administration of 5.67 GBq to the right lobe of the liver for a target dose of 120 Gy. The licensee estimated the delivered dose to be approximately 123 Gy.

A post-treatment Bremsstrahlung scan indicated that delivery was segmental to the caudate lobe of the liver and surrounding tissue. Two SPEC-CT scans were performed and revealed delivery near the gallbladder fossa (patient does not have a gallbladder). The authorized user determined that activity was delivered outside the intended area, with some in the liver and some in the tissue or ductal interworking around the liver.

The patient was informed of the findings. A written report, containing all information required under 10 CFR 35.3045(d), will be submitted within 15 days of discovery.

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 - STUCK SHUTTER

The following information was provided by the Tennessee Division of Radiation Health via email:

"During a scheduled six-month shutter check, it was discovered that a gauge shutter was stuck in the open position. No abnormal levels of radiation were detected. Open is the normal operating position since the unit is in operation 24 hours a day. A vendor field technician has been contacted to repair the gauge on October 20, 2026.

"Corrective actions or reports, as well as additional information, will be updated with a NMED report within 30 days."

Gauge: Ohmart/VEGA source holder model SH-F1
Source: 50 mCi Cs-137 (S/N 01908)

Tennessee incident number: TN-26-081

AGREEMENT STATE REPORT - MEDICAL EVENT

The following is a summary of information provided by the Maryland Department of the Environment, Radiological Health Program (MDE/RHP) via email:

On October 13, 2026, at 1659 EDT, staff from MDE/RHP received a call from the licensee regarding a Y-90 microsphere medical event that occurred on October 12, 2026, at 0915 EDT.

The patient was prescribed approximately 60.1 mCi for treatment of liver cancer in segments 2 and 3, with an intended dose to the liver of 370 Gy.

The licensee reported performing pre-treatment scans that showed no significant concern for shunting. Post-treatment imaging identified unintended activity in the left gastric artery and gastric fundus/cardia, indicating that an estimated 2 to 2.5 percent of the administered activity refluxed into the area of the left gastric artery.

Preliminary dose estimates indicate the unintended exposure may have delivered approximately 56 to 93 Gy to the stomach (fundus/cardia region), about 19 Gy to the stomach wall, and 1,390 to 2,800 Gy to the left gastric artery wall.

The patient and referring physician were notified. The patient was started on a prophylactic proton pump inhibitor (PPI) therapy.

MDE/RHP is evaluating the event and will provide additional information as it becomes available.

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.