Event Notification Report for June 24, 2024

EN Revision Imported Date: 6/24/2024

EN Revision Text: PART 21 - DEFECT WITH EMERGENCY DIESEL GENERATOR VOLTAGE REGULATOR

The following information was provided by Paragon Energy Solutions, LLC via email:

"Paragon has identified a defect in one voltage regulator supplied to AEP DC Cook with serial number NLI-3S7950GR751A1-1007.

"Pursuant to 10CFR Part 21  21.21(d)(3)(i), Paragon is providing initial notification of a defect associated with the emergency diesel generator (EDG) voltage regulator. The voltage regulator was refurbished under the client purchase order 01600229, project number 351030025. Part of the refurbishment involved complete replacement of the units wiring, physical inspection and testing of the unit to Paragon approved acceptance testing instructions. The refurbished unit was supplied to the customer in December 2023. Prior to installation (March 2024), the unit successfully passed bench testing at the plant. During post installation testing, the EDG was started, and the output voltage pegged high and was not controllable. DC Cook subsequently removed the voltage regulator and documented the non-conformance. DC Cook troubleshooting determined the unit was mis-wired. The unit [voltage regulator] was returned to Paragon, and inspection confirmed the plant's diagnosis. The identified mis-wire affects the system circuitry by placing silicon controlled rectifier 5CD in a reverse biased position. The reversed biased rectifier blocks the flow of current which creates an open circuit condition. This open circuit condition causes the output voltage to max out, and does not allow the output voltage to be adjusted. This condition, if left uncorrected, could contribute to a substantial safety hazard and is reportable in accordance with 10CFR Part 21.

"Date of Discovery: May 9, 2024

"Reportability Determined: May 23, 2024

"Paragon has entered this condition in our corrective action program, and we have custody of the effected unit. The extent of condition is limited to this unit supplied to DC Cook. Paragon has determined there is no action necessary for DC Cook at this time."

Affected plant: DC Cook

* * * UPDATE ON 06/21/2024 AT 1655 EDT FROM RICHARD KNOTT TO ROBERT THOMPSON * * *

Paragon Energy Solutions submitted a final report for this event documenting the cause of the mis-wire and corrective actions to prevent recurrence.

Paragon contact: Richard Knott, Vice President Quality Assurance, Paragon Energy Solutions, LLC, 7410 Pebble Drive, Ft. Worth, TX 76118, 817-284-0077, rknott@paragones.com.

Notified R3DO (Havertape), R4DO (Josey), and Part 21 (email).

AGREEMENT STATE REPORT - STOLEN TROXLER GAUGE

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

"On June 14, 2024, an employee of the licensee reported to police that their vehicle, with a nuclear density gauge secured in the trunk, was stolen earlier that day. Local police are aware of the incident. The DEP has been in contact with the licensee and will update this event as soon as more information is provided.

"Manufacturer and Model Number: Troxler Electronic Laboratories
"Model Number: 3440
"Serial Number: 35459
"Isotope and Activity: Cesium 137, 9 millicuries; Americium 241:Be, 44 millicuries."

PA Event Report ID No: PA240012

Surrounding States and the Pennsylvania emergency response team have been notified.

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 - BURNABLE POISON ROD ASSEMBLY MISLOAD

The following is a synopsis of information provided by Framatome, Inc. (Framatome) via email:

During startup testing at the affected plant, unexpected high reactor peaking factor readings resulted from an incorrect boron concentration of Al2O3-B4C pellets in two burnable poison rod assemblies (BPRAs). The cause of the issue was due to 0.2 percent boron concentration Al2O3-B4C pellets inadvertently combined with the intended 2.0 percent boron concentration Al2O3-B4C pellets, which were then placed back into inventory labeled as 2.0 percent.

This issue was determined to be a 10 CFR 21 Defect on June 21, 2024.

Corrective actions are that Framatome replaced the two affected BPRAs with BPRAs fabricated correctly and a root cause analysis has been initiated by Framatome which is scheduled for completion by July 31, 2024.

The affected plant is Oconee Unit 3.

The name and address of the individual reporting this information is:
Gayle Elliott
Director, Licensing & Regulatory Affairs
Framatome Inc.
Office 434 832-3347
Mobile 434 841-0306
3315 Old Forest Road
Lynchburg, VA 24501
gayle.elliott@framatome.com

MANUAL ACTUATION OF REACTOR PROTECTION SYSTEM (RPS)

The following information was provided by the licensee via email:

"At 0728 EDT on 06/22/2024, with Unit 2 in Mode 3 at zero percent power and the reactor trip breakers closed, a manual actuation of the RPS was initiated during the withdrawal of the shutdown rods in preparation for Mode 2. This was procedurally directed due to a shutdown rod being misaligned from the other rods in the bank due to a malfunction.

"Units 1, 3 and 4 were not affected.

"Due to the manual actuation of the RPS, this event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(iv)(A).

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