ML25350C111
| ML25350C111 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 12/17/2025 |
| From: | Erin Carfang Division of Operating Reactors |
| To: | Carr E Dominion Energy |
| References | |
| IR 2025011 | |
| Download: ML25350C111 (0) | |
Text
December 17, 2025 Eric S. Carr Chief Nuclear Officer and President - Nuclear Operations and Contracted Energy Dominion Energy, Inc.
Innsbrook Technical Center 5000 Dominion Blvd.
Glen Allen, VA 23060-6711
SUBJECT:
MILLSTONE POWER STATION, UNITS 2 AND 3 - DESIGN BASIS ASSURANCE INSPECTION (PROGRAMS) INSPECTION REPORT 05000336/2025011 AND 05000423/2025011
Dear Eric Carr:
On December 10, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Millstone Power Station, Units 2 and 3, and discussed the results of this inspection with James Petty, Senior Vice President, and other members of your staff. The results of this inspection are documented in the enclosed report.
No findings or violations of more than minor significance were identified during this inspection.
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, Erin E. Carfang, Chief Engineering Branch 1 Division of Operating Reactor Safety Docket Nos. 05000336 and 05000423 License Nos. DPR-65 and NPF-49
Enclosure:
As stated cc w/ encl: Distribution via LISTSERV ERIN CARFANG Digitally signed by ERIN CARFANG Date: 2025.12.17 08:06:39 -05'00'
SUNSI Review
Non-Sensitive
Sensitive
Publicly Available
Non-Publicly Available OFFICE RI/DORS RI/DORS NAME KMangan ECarfang DATE 12/16/2025 12/15/2025
Enclosure U.S. NUCLEAR REGULATORY COMMISSION Inspection Report Docket Numbers:
05000336 and 05000423 License Numbers:
DPR-65 and NPF-49 Report Numbers:
05000336/2025011 and 05000423/2025011 Enterprise Identifier: I-2025-011-0011 Licensee:
Dominion Energy Nuclear Connecticut, Inc.
Facility:
Millstone Power Station, Units 2 and 3 Location:
Waterford, CT Inspection Dates:
September 22, 2025 to December 10, 2025 Inspectors:
K. Mangan, Senior Reactor Inspector S. McClay, Reactor Inspector J. Tifft, Senior Reactor Inspector Approved By:
Erin E. Carfang, Chief Engineering Branch 1 Division of Operating Reactor Safety
2
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a design basis assurance inspection (programs) inspection at Millstone Power Station, Units 2 and 3, 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 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 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 71111.21N.04 - Age-Related Degradation Age-Related Degradation (8 Samples)
The inspectors selected a sample of components and structures to verify that engineering performance and maintenance activities addressed age-related degradation and that problems were appropriately identified, addressed, and corrected.
Samples were selected considering risk insights and the potential for degradation.
Specifically, the inspectors selected samples that were risk-significant and either had indications of age-related degradation or were exposed to environments that could cause age-related degradation. The inspectors considered site-specific and industry-wide operating experience to identify samples and included both active and passive sub-components within each component or structure.
For each selected sample listed below, the inspectors reviewed the licensees engineering and maintenance activities credited to address age-related degradation to assess whether they were being performed using applicable standards and procedures, evaluated against appropriate acceptance criteria, and that maintenance and condition monitoring was completed at an appropriate interval. The inspectors also assessed whether issues identified during licensee activities were being entered into and addressed by the applicable station processes including the corrective action program, and whether periodic assessments of maintenance effectiveness and operating experience were being completed, including feedback and process adjustments.
(1)
Unit 2, reactor building component cooling water pump (2)
Unit 3, containment recirculation spray pump (3)
Unit 3, service water strainer (4)
Unit 3, turbine driven auxiliary feedwater (5)
Unit 2, low pressure safety injection (6)
Unit 2, service water piping (7)
Unit 3, ventilation fans and dampers (8)
Units 2 and 3, station blackout diesel INSPECTION RESULTS No findings were identified.
4 EXIT MEETINGS AND DEBRIEFS The inspectors verified no proprietary information was retained or documented in this report.
On December 10, 2025, the inspectors presented the design basis assurance inspection (programs) inspection results to James Petty, Senior Vice President, and other members of the licensee staff.
5 DOCUMENTS REVIEWED Inspection Procedure Type Designation Description or Title Revision or Date 71111.21N.04 Calculations 2017PA3056881_ECA 0.3 Unit 3 Programs Operator Credited Actions Corrective Action Documents 1011518 1105574 1106152 1155099 1155384 1179384 1183162 1188959 1201174 1201734 1210262 1221101 1227813 1236949 1249189 1250708 1252360 1252856 1257537 1258562 1264523 1264815 1294466 1295635 1296885 1220972 Corrective Action Documents Resulting from Inspection 1302414 1302455 1308827 1308808
6 Inspection Procedure Type Designation Description or Title Revision or Date Engineering Evaluations RCE: CA 118894 Service Water Pipe & Support Degradation in MP2 Service Water Pipe Tunnel REA for Start Air Drying Skid MP-2023-014 Procedures MP 3704A-600 SLCRS Isolation Damper Inspection 004 MP-PROC-ENG-EN 21243 Millstone Unit 2 Service Water Pipe Liner/Coating Inspection, Preventative Maintenance and Surveillance Program 14 OP 3314J Auxiliary Building Emergency Ventilation and Exhaust 006-00 SP 3670.4, MP-PROC-OPS-OP 3346D, MP-PROC-OPS-EOP 35 ECA-0.0, MP-PROC-OPS-EOP 35 ECA-0.3, ER-AA-EDG-1001 Routine PMs, Station Blackout Diesel, Loss of All AC Power, Loss of All AC Power - Recovery with the SBO Diesel, Diesel Generator Reliability Program Work Orders WO 22214912 WO 22492314 WO 53102884917 WO 53203338428 WO 53203357596 WO 53203439228 WO 53203439247 WO 53102887344 WO 53203468036