Event Notification Report for May 20, 2024

EN Revision Imported Date: 5/20/2024

EN Revision Text: PART 21 - INTERIM REPORT FOR OIL FILLED CAPACITORS

The following is a synopsis of information that was provided by AMETEK Solidstate Controls Inc. via email:

This component (07-020139-10) is a 13 micro-Farad AC oil filled capacitor. During operation in an inverter, oil may be visible on, around, or dripping from the capacitor or its mounting bracket or tray. If allowed sufficient time, enough oil will leak from the capacitor that it will short internally and fail. Time required for the failure could be greater than the recommended 10-year preventative maintenance cycle for this part.

AMETEK Solidstate Controls has not been able to determine a definitive cause of the failure, but is working to do so.

These capacitors are generally part of a larger capacitor bank. The failure would result in a reduction of output voltage that is directly proportional to the number of capacitors in the bank that fail. Any single capacitor failure would be less than a 3 volt decrease in output voltage.

Users of these capacitors should visually inspect any equipment containing the capacitor part number stated above for evidence of an oil leak. A review of the output voltage for the parent equipment for any consistent decrease in voltage of 0-3V may serve as an indication of capacitor failure. The user should notify AMETEK Solidstate Controls if any oil is observed during inspection.

Corrective actions should be established by May 2024.

Affected plants are not listed.

* * * UPDATE ON 05/17/24 AT 1305 EDT FROM ZACHARY RUMORA TO KAREN COTTON * * *

FINAL REPORT FOR OIL FILLED CAPACITORS

AMETEK Solidstate Controls Inc, (SCI) has completed their evaluation of the deviation described in their interim report submitted on February 9, 2024, and concluded that there was no way of recreating the potential defect and no evidence of a broad defect with the general design, manufacture, or use of the capacitor. However, they identified hypothesized causes of the failure and corrective actions to mitigate failure risks. AMETEK SCI also identified the end users that may be potentially affected.

The affected plants are Duke Energy; Oconee and Catawba, TVA; Browns Ferry and Watts Bar; Georgia Power, Vogtle 1 and 2; Dominion; Surry; and South Texas Nuclear Operating Company.

Notified R2DO(Miller), R4DO(Josey) and Part 21/50.55 Reactors (email)

DAMAGED GAUGE

The following synopsis of the event was provided by the licensee via phone:

On the afternoon of May 9, 2024, during a leak test, the licensee identified a damaged shutter on a gauge (Serial Number - SH-F180) with a cesium (Cs-137) source of 100 millicuries at their facility. The licensee determined that no exposures or injuries occurred as a result of the damaged shutter since the gauge is located twenty feet off the ground in a primarily inaccessible location. No surveys are known to have been performed at this time. The shutter was determined to be unworkable, and is scheduled to be replaced at a later date.

* * * Additional information provided on 5/10/24 at 1327 EDT from B. Elkins to T. Herrity * * *
The license number was originally reported as 373525501 but it should actually be 16-35383-01. Unit is 10 feet above the floor not 20 feet. Survey readings have been taken: 25.65 mR/hr at the surface; 1.73 mR/hr at 1 foot; 0.32 mR/hr at 3 feet; 0.05 mR/hr at 4 feet. Based on the survey readings, it is believed that the shutter is closed. The mine is now looking to repair the shutter control unit, not replace the gauge.

Notified R1DO (Young) and NMSS Events via email.

REACTOR WATER CLEANUP SYSTEM ISOLATION CHANNEL INOPERABLE

The following information was provided by the licensee via email:

"On May 16, 2024 at 0840 EDT, operations declared the reactor water cleanup (RWCU) leak detection instruments related to the high differential flow signal inoperable. Technical specification (TS) 3.3.6.1, primary containment and drywell isolation instrumentation, conditions `A' and `B' were entered as one required channel of instrumentation was inoperable, and an automatic function with isolation capability was not maintained. Therefore, this condition is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(v)(C) and 10 CFR 50.72(b)(3)(v)(D). All other RWCU primary containment isolation instrumentation functions remained operable.

"At 1210 EDT, the affected leak detection instruments were declared operable, and the TS limiting condition for operation 3.3.6.1 was declared met.

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

MANUAL REACTOR TRIP

The following information was provided by the licensee via email:

"At 0030 [EDT] on 5/19/24, with Beaver Valley Unit 1 in mode 1 at 14 percent power, the reactor was manually tripped due to inability to control the 'A' steam generator water level. The trip was not complex, with all systems responding normally post-trip. The turbine driven auxiliary feedwater pump automatically started on a valid actuation signal. All control rods inserted into the core. Operations responded and stabilized the plant. Decay heat is being removed by the feedwater system and the main condenser. Beaver Valley Unit 2 is unaffected.

"Due to the reactor protection system system actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B). Due to the emergency safety feature system actuation (automatic start of the turbine driven auxiliary feedwater pump) while critical, this event is being reported as an eight-hour, non-emergency notification per 10CFR 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 verbally notified."


The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
Unit 1 is stable on off-site power, normal configuration. All emergency systems are available.