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Nuclear Station - Integrated Inspection Report 05000369/2025003 and 05000370/2025003
	ML25328A131
Person / Time
Site:	McGuire, Mcguire
Issue date:	11/26/2025
From:	Robert Williams; NRC/RGN-II/DORS
To:	Pigott E; Duke Energy Carolinas
References
	IR 2025003
	Download: ML25328A131 (0)
	v • d • e

Edward Pigott Site Vice President McGuire Nuclear Station Duke Energy Carolinas, LLC 12700 Hagers Ferry Road Huntersville, NC 28078

SUBJECT:

MCGUIRE NUCLEAR STATION - INTEGRATED INSPECTION REPORT 05000369/2025003 AND 05000370/2025003

Dear Edward Pigott:

On September 30, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at McGuire Nuclear Station. On November 19, 2025, the NRC inspectors discussed the results of this inspection with you and other members of your staff. The results of this inspection are documented in the enclosed report.

Due to the temporary cessation of government operations, which commenced on October 1, 2025, the NRC began operating under its Office of Management and Budget-approved plan for operations during a lapse in appropriations. Consistent with that plan, the NRC operated at reduced staffing levels throughout the duration of the shutdown. However, the NRC continued to perform critical health and safety functions and make progress on other high-priority activities associated with the ADVANCE Act and Executive Order 14300. On November 13, 2025, following the passage of a continuing resolution, the NRC resumed normal operations. However, due to the 43-day lapse in normal operations, the Office of Nuclear Reactor Regulation granted the Regional Offices an extension on the issuance of the calendar year 2025, 3rd quarter integrated inspection reports normally issued by November 15, 2025, to December 31, 2025. The NRC will resume the routine cycle of issuing inspection reports on a quarterly basis beginning with the calendar year 2025, 4th quarter integrated inspection reports, which will be issued 45 days after the 4th quarter ends on December 31, 2025.

No findings or violations of more than minor significance were identified during this inspection.

November 26, 2025

E. Pigott 2

This letter, its enclosure, and your response (if any) will be made available for public inspection and copying at http://www.nrc.gov/reading-rm/adams.html and at the NRC Public Document Room in accordance with Title 10 of the Code of Federal Regulations 2.390, Public Inspections, Exemptions, Requests for Withholding.

Sincerely, Robert E. Williams, Jr., Chief Projects Branch 1 Division of Operating Reactor Safety Docket Nos. 05000369 and 05000370 License Nos. NPF-9 and NPF-17

Enclosure:

As stated cc w/ encl: Distribution via LISTSERV Signed by Williams, Robert on 11/26/25

ML25328A131 x

SUNSI Review x

Non-Sensitive

Sensitive x

Publicly Available

Non-Publicly Available OFFICE RII/DORS RII/DORS RII/DORS NAME C. Safouri D. Jackson R. Williams Jr.

DATE 11/24/2025 11/24/2025 11/26/2025

Enclosure U.S. NUCLEAR REGULATORY COMMISSION Inspection Report Docket Numbers:

05000369 and 05000370 License Numbers:

NPF-9 and NPF-17 Report Numbers:

05000369/2025003 and 05000370/2025003 Enterprise Identifier:

I-2025-003-0023 Licensee:

Duke Energy Carolinas, LLC Facility:

McGuire Nuclear Station Location:

Huntersville, North Carolina Inspection Dates:

July 1, 2025, to September 30, 2025 Inspectors:

C. Safouri, Senior Resident Inspector F. Young, Resident Inspector S. Battenfield, Operations Engineer K. Lei, Emergency Preparedness Inspector M. Rich, Emergency Preparedness Inspector J. Tornow, Physical Security Inspector J. Walker, Senior Emergency Preparedness Inspector Approved By:

Robert E. Williams, Jr., Chief Projects Branch 1 Division of Operating Reactor Safety

2

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at McGuire Nuclear Station, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.

List of Findings and Violations No findings or violations of more than minor significance were identified.

Additional Tracking Items None.

3 PLANT STATUS Unit 1 operated at or near 100 percent rated thermal power (RTP) for the entire inspection period.

Unit 2 operated at or near 100 percent RTP for the entire inspection period.

INSPECTION SCOPES Inspections were conducted using the appropriate portions of the inspection procedures (IPs) in effect at the beginning of the inspection unless otherwise noted. Currently approved IPs with their attached revision histories are located on the public website at http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/index.html. Samples were declared complete when the IP requirements most appropriate to the inspection activity were met consistent with Inspection Manual Chapter (IMC) 2515, Light-Water Reactor Inspection Program - Operations Phase. The inspectors performed activities described in IMC 2515, Appendix D, Plant Status, observed risk significant activities, and completed on-site portions of IPs. The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel to assess licensee performance and compliance with Commission rules and regulations, license conditions, site procedures, and standards.

REACTOR SAFETY 71111.04 - Equipment Alignment Partial Walkdown Sample (IP Section 03.01) (2 Samples)

The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:

(1)

Unit 1 and Unit 2 auxiliary feedwater (CA) pumps assured suction sources from nuclear service water system, on July 23, 2025 (2)

Unit 1 and Unit 2 interior doghouses, including portions of the main steam system, main steam vent to atmosphere system, and main steam supply to auxiliary equipment for steam generators 1B, 1C, 2B, and 2C, on September 6, 2025 71111.05 - Fire Protection Fire Area Walkdown and Inspection Sample (IP Section 03.01) (2 Samples)

The inspectors evaluated the implementation of the fire protection program by conducting a walkdown and performing a review to verify program compliance, equipment functionality, material condition, and operational readiness of the following fire areas:

(1)

Unit 2 train A and train B 4160V switchgear and electrical penetration rooms, on July 25, 2025 (2)

Unit 1 and Unit 2 shared equipment areas of auxiliary building elevation 716 and mechanical penetration rooms, on August 22, 2025

4 71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance Licensed Operator Performance in the Actual Plant/Main Control Room (IP Section 03.01)

(1 Sample)

(1)

The inspectors observed and evaluated licensed operator performance in the control room during Unit 1 rod cluster control assembly bank repositioning, on August 11, 2025, and Unit 1 train B main feedwater pump high pressure governor steam leak in the turbine building, on August 12, 2025.

Licensed Operator Requalification Training/Examinations (IP Section 03.02) (4 Samples)

(1)

The inspectors observed and evaluated annual requalification operating testing, on July 22, 2025 (2)

The inspectors observed and evaluated annual requalification operating testing, on July 24, 2025 (3)

The inspectors observed and evaluated annual requalification operating testing, on July 29, 2025 (4)

The inspectors observed and evaluated annual requalification operating testing, on August 5 and 8, 2025 71111.12 - Maintenance Effectiveness Maintenance Effectiveness (IP Section 03.01) (2 Samples)

The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components remain capable of performing their intended function:

(1)

Nuclear condition report (NCR) 02526647, Unit 1 train A diesel generator (D/G) battery charger failure, on July 15, 2025 (2)

NCRs 02540897 and 02541049, Unit 2 train A CA suction swap over pressure switches, 2CAPS5002 and 2CAPS5350, found out of tolerance during calibration, on September 10, 2025 71111.13 - Maintenance Risk Assessments and Emergent Work Control Risk Assessment and Management Sample (IP Section 03.01) (1 Sample)

The inspectors evaluated the accuracy and completeness of risk assessments for the following planned and emergent work activities to ensure configuration changes and appropriate work controls were addressed:

(1)

NCR 02566232, Unit 1 turbine driven CA pump implementation of risk-informed completion time in response to an emergent gearbox seal issue, on August 28, 2025

5 71111.15 - Operability Determinations and Functionality Assessments Operability Determination or Functionality Assessment (IP Section 03.01) (5 Samples)

The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:

(1)

NCR 02560176, Unit 1 train B D/G control air to shutdown cylinders solenoid failure, 1VGSV5171, on July 2, 2025 (2)

NCR 02535481, station lubrication manual discrepancies for Unit 1 and Unit 2 diesel ventilation fan motors, on July 2, 2025 (3)

NCR 02540358, Unit 1 turbine driven CA pump bearing vibrations in alert range, on July 17, 2025 (4)

NCR 02566122, diesel building ventilation calculation indicating classification as a harsh environment per 10 CFR 50.49, on August 18, 2025 (5)

Room temperature gradient and annunciator response during Unit 1 train A D/G 24-hour surveillance run, on August 18, 2025 71111.24 - Testing and Maintenance of Equipment Important to Risk The inspectors evaluated the following testing and maintenance activities to verify system operability and/or functionality:

Post-Maintenance Testing (PMT) (IP Section 03.01) (4 Samples)

(1)

PT/0/A/4200/002, "Standby Shutdown Facility Operability Test," following standby shutdown facility planned maintenance window, on July 8, 2025 (2)

PT/0/A/4350/028B, "125 Volt Vital Battery Quarterly Inspection," for Unit 1 and Unit 2 shared vital battery, EVCD, following equalizing charge, on July 30, 2025 (3)

PT/1/A/4350/002A, "Diesel Generator 1A Operability Test," following Unit 1 train A D/G 24-hour run and subsequent maintenance, on August 21, 2025 (4)

PT/1/A/4252/001, "Unit 1 Turbine Driven Auxiliary Feedwater Pump Performance Test," and PT/1/A/4252/007, "Auxiliary Feedwater System Turbine Driven Train Performance Test," following replacement of turbine governor gearbox shaft seal, on August 29, 2025 Surveillance Testing (IP Section 03.01) (3 Samples)

(1)

Unit 1 upper personnel airlock overall leak rate test, on July 31, 2025 (2)

Unit 2 channel IV power range ex-core nuclear instrument channel, 2N-44, channel operational test, on July 31, 2025 (3)

Unit 2 loop A, B, C, and D reactor coolant pump undervoltage and underfrequency 18-month calibration and functional test, on August 4, 2025 71114.01 - Exercise Evaluation Inspection Review (IP Section 02.01-02.11) (1 Sample)

(1)

The inspectors evaluated the biennial emergency plan exercise during the week of August 26, 2025. The simulated scenario began with a small leak on the reactor cold leg exceeding the threshold value for declaration of an Unusual Event. A short time

6 later, an auxiliary feed pump failed to start due to a breaker issue, while concurrently the reactor failed to trip thus meeting the conditions for declaration of an Alert. As the scenario progressed, the turbine driven CA pump tripped due to a governor link issue.

The loss of heat sink resulted in a red critical safety functional area, thus meeting the conditions for declaration of a Site Area Emergency. The Offsite Response Organizations were able to demonstrate their ability to implement emergency actions.

71114.04 - Emergency Action Level and Emergency Plan Changes Inspection Review (IP Section 02.01-02.03) (1 Sample)

(1)

The inspectors evaluated submitted Emergency Action Level, Emergency Plan, and Emergency Plan Implementing Procedure changes during the week of August 25, 2025. This evaluation does not constitute NRC approval.

71114.06 - Drill Evaluation Additional Drill and/or Training Evolution (1 Sample)

(1)

The inspectors evaluated an emergency preparedness drill that consisted of a faulted steam generator tube rupture, on September 24, 2025.

71114.08 - Exercise Evaluation - Scenario Review Inspection Review (IP Section 02.01 - 02.04) (1 Sample)

(1)

The inspectors reviewed and evaluated in-office, the proposed scenario for the biennial emergency plan exercise at least 30 days prior to the day of the exercise.

OTHER ACTIVITIES - BASELINE 71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:

MS08: Heat Removal Systems (IP Section 02.07) (2 Samples)

(1)