ML25357A024
| ML25357A024 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 12/23/2025 |
| From: | Jason Schussler Division of Operating Reactors |
| To: | Mudrick C Constellation Energy Generation, Constellation Nuclear |
| References | |
| IR 2025003 | |
| Download: ML25357A024 (0) | |
Text
December 23, 2025 Christopher H. Mudrick Senior Vice President and Chief Nuclear Officer Constellation Energy Generation, LLC President Constellation Nuclear 200 Energy Way, KSA-3N Kennett Square, PA 19348
SUBJECT:
NINE MILE POINT NUCLEAR STATION, UNITS 1 AND 2 - INTEGRATED INSPECTION REPORT 05000220/2025003 AND 05000410/2025003
Dear Christopher Mudrick:
On September 30, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Nine Mile Point Nuclear Station, Units 1 and 2. On December 18, 2025, the NRC inspectors discussed the results of this inspection with Tim Peter, Site Vice President, 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, third 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, fourth quarter integrated inspection reports, which will be issued 45 days after the fourth quarter ends on December 31, 2025.
No findings or violations of more than minor significance were identified during this inspection.
C. Mudrick 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, Jason E. Schussler, Chief Projects Branch 1 Division of Operating Reactor Safety Docket Nos. 05000220 and 05000410 License Nos. DPR-63 and NPF-69
Enclosure:
As stated cc w/ encl: Distribution via LISTSERV JASON SCHUSSLER Digitally signed by JASON SCHUSSLER Date: 2025.12.23 09:09:07 -05'00'
ML25357A024 SUNSI Review Non-Sensitive Sensitive Publicly Available Non-Publicly Available OFFICE RI/DORS RI/DORS RI/DORS NAME EMiller DBeacon JSchussler DATE 12/23/2025 12/23/2025 12/23/2025
Enclosure U.S. NUCLEAR REGULATORY COMMISSION Inspection Report Docket Numbers:
05000220 and 05000410 License Numbers:
DPR-63 and NPF-69 Report Numbers:
05000220/2025003 and 05000410/2025003 Enterprise Identifier: I-2025-003-0046 Licensee:
Constellation Energy Generation, LLC Facility:
Nine Mile Point Nuclear Station, Units 1 and 2 Location:
Oswego, NY Inspection Dates:
July 1, 2025 to September 30, 2025 Inspectors:
E. Miller, Senior Resident Inspector E. Adams, Resident Inspector B. Sienel, Resident Inspector C. Borman, Health Physicist C. Kline, Senior Resident Inspector E. Miller, Senior Reactor Inspector Approved By:
Jason E. Schussler, 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 Nine Mile Point 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 began the inspection period at rated thermal power. On September 19, 2025, operators reduced reactor power to 80 percent to perform planned generator brush replacement on the 12 reactor water recirculation motor generator, planned turbine valve testing, control rod friction testing, control rod scram time testing, and a control rod pattern adjustment. Operators restored reactor power to rated thermal power on September 20, 2025. Unit 1 remained at or near rated thermal power for the rest of the inspection period.
Unit 2 began the inspection period at rated thermal power. On September 27, 2025, operators reduced reactor power to 85 percent to evaluate for a potential fuel cladding defect. Operators restored reactor power to rated thermal power on September 28, 2025. Unit 2 remained at rated thermal power for the rest of the 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) (3 Samples)
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
(1)
Unit 1 emergency diesel generator (EDG) 102 on July 9, 2025 (2)
Unit 2 reactor core isolation cooling (RCIC) on August 6, 2025 (3)
Unit 1 EDG 103 on September 22, 2025 Complete Walkdown Sample (IP Section 03.02) (1 Sample)
The inspectors evaluated system configurations during a complete walkdown of the following system:
(1)
Unit 1 containment spray system on August 12, 2025 71111.05 - Fire Protection Fire Area Walkdown and Inspection Sample (IP Section 03.01) (2 Samples)
4 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 control building 261' high pressure core spray switchgear room, fire area 21, on August 6, 2025 (2)
Unit 2 reactor building 261' south general area, fire area 35, on August 21, 2025 71111.06 - Flood Protection Measures Flooding Sample (IP Section 03.01) (1 Sample)
(1)
The inspectors evaluated internal flooding mitigation protections in the Unit 2 control building 236' pipe tunnel on September 23, 2025.
71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance Licensed Operator Performance in the Actual Plant/Main Control Room (IP Section 03.01)
(2 Samples)
(1)
The inspectors observed and evaluated Unit 1 licensed operator performance in the control room during control rod friction testing and load line adjustment on August 31, 2025.
(2)
The inspectors observed and evaluated Unit 2 licensed operator performance in the control room during a power reduction to 85 percent and reactor puff testing on September 27 and 28, 2025.
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (2 Samples)
(1)
The inspectors observed a Unit 1 simulator evaluation that included an inadvertent initiation of reactor building emergency ventilation, a pressure regulator failure, a transformer fault, and a scram with a leak in containment on August 19, 2025.
(2)
The inspectors observed a Unit 2 simulator evaluation that included a failure of the Division I reactor protection system, a loss of emergency switchgear bus 102, a feedwater level control flow instrument failure, and a scram with fuel failure requiring reactor pressure vessel blowdown resulting in an Alert declaration on August 19, 2025.
71111.12 - Maintenance Effectiveness Maintenance Effectiveness (IP Section 03.01) (3 Samples)
The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components (SSCs) remain capable of performing their intended functions:
(1)
Unit 2 control room special filter train booster fan trip on September 10, 2025 (2)
Unit 2 degraded cooling tower spray pipe on September 16, 2025 (3)
Unit 2 degraded service water piping on September 17, 2025
5 Quality Control (IP Section 03.02) (1 Sample)
The inspectors evaluated the effectiveness of maintenance and quality control activities to ensure the following SSC remains capable of performing its intended function:
(1)
Commercial grade dedication of capacitors installed in Unit 1 average power range monitor channel 13 local power range monitor power supplies on September 29, 2025 71111.13 - Maintenance Risk Assessments and Emergent Work Control Risk Assessment and Management Sample (IP Section 03.01) (4 Samples)
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)
Unit 1 elevated risk during 122 containment spray maintenance on July 9, 2025 (2)
Unit 2 elevated risk during execution of risk informed completion time associated with inoperability of a main steam line area temperature instrument on July 22, 2025 (3)
Unit 1 elevated risk during planned 115 kilovolt Line 4 offsite maintenance the week of September 22, 2025 (4)
Unit 1 elevated risk during replacement of reactor protection system channel 12 emergency cooling initiation relay on September 25, 2025 71111.15 - Operability Determinations and Functionality Assessments Operability Determination or Functionality Assessment (IP Section 03.01) (6 Samples)
The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:
(1)
Unit 2 main steam line tunnel high temperature on July 11, 2025 (2)
Unit 2 service water pump bay area cooler 2HVY*U2CD performance test failure on July 14, 2025 (3)
Unit 2 RCIC isolation off/power loss inoperable status light on July 28, 2025 (4)
Unit 2 reactor protection system steam tunnel temperature delta instrument with correction applied on August 18, 2025 (5)
Unit 2 chill water solenoid isolation valve 2HVK*SOV36B closure time outside of inservice testing criteria on August 28, 2025 (6)
Unit 1 reactor water recirculation pump 12 low pressure seal following elevated pressure trend on September 17, 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) (7 Samples)
6 (1)
Unit 1 containment spray system 122 following repairs to containment spray 122 suction isolation valve on July 8, 2025 (2)
Diverse and flexible coping strategies (FLEX) diesel 'B' unloaded run following battery replacement on July 14, 2025 (3)
Unit 2 RCIC alarm circuit following circuit card replacement on August 8, 2025 (4)
Unit 1 EDG 103 following planned 12-year preventive maintenance on September 12, 2025 (5)
Unit 1 EDG 103 air start solenoid SOV-96-108 following O-ring replacement on September 12, 2025 (6)
Unit 1 EDG 103 air start solenoid BV-96-107 following gasket replacement on September 12, 2025 (7)
Unit 1 reactor protection system channel 12 emergency cooling initiation relay following failure to reset on September 25, 2025 Surveillance Testing (IP Section 03.01) (1 Sample)
(1)
N2-OSP-RHS-Q@005, RHR [Residual Heat Removal] System Loop B Pump and Valve Operability Test, on July 31, 2025 Diverse and Flexible Coping Strategies (FLEX) Testing (IP Section 03.02) (1 Sample)
(1)
S-PM-003, FLEX Diesel B Loaded Run, on July 15, 2025 RADIATION SAFETY 71124.06 - Radioactive Gaseous and Liquid Effluent Treatment Walkdowns and Observations (IP Section 03.01) (3 Samples)
The inspectors evaluated the following radioactive effluent systems during walkdowns:
(1)
Unit 2 stack and vent wide-range gas monitor 2RMS-PN2170A (2)
Unit 1 emergency condenser vent radiation monitors RAD-MON-112 and RAD-MON-122 (3)
Unit 1 stack off-gas effluent system monitoring system RR-112-07/08 Sampling and Analysis (IP Section 03.02) (3 Samples)
Inspectors evaluated the following effluent samples, sampling processes and compensatory samples:
(1)
Iodine and particulate samples taken from the Unit 2 stack and vent wide-range gaseous monitoring system (2)
Iodine and particulate samples taken from the Unit 1 stack and vent off-gas effluent stack monitoring system (3)
Iodine and particulate analysis for the Unit 1 off-gas effluent stack monitoring system (sample 17-JUL-25-210001) and the Unit 2 stack and vent wide-range gaseous monitoring system (sample 15-JUL-25-22003)
7 Dose Calculations (IP Section 03.03) (2 Samples)
The inspectors evaluated the following dose calculations:
(1)
Unit 1 emergency condenser vent discharge liquid permit L-2025-03-100 (2)
Unit 2 gas release permit G-20250609-1492-C Abnormal Discharges (IP Section 03.04) (1 Sample)
(1)
There were no abnormal discharges for evaluation during the inspection.
OTHER ACTIVITIES - BASELINE 71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
MS05: Safety System Functional Failures Sample (IP Section 02.04) (2 Samples)
(1)
Unit 1 for the period July 1, 2024 through June 30, 2025 (2)
Unit 2 for the period July 1, 2024 through June 30, 2025 MS06: Emergency AC Power Systems (IP Section 02.05) (2 Samples)
(1)
Unit 1 for the period July 1, 2024 through June 30, 2025 (2)
Unit 2 for the period July 1, 2024 through June 30, 2025 MS07: High Pressure Injection Systems (IP Section 02.06) (2 Samples)
(1)
Unit 1 for the period July 1, 2024 through June 30, 2025 (2)
Unit 2 for the period July 1, 2024 through June 30, 2025 INSPECTION RESULTS No findings were identified.
EXIT MEETINGS AND DEBRIEFS The inspectors verified that no proprietary information was retained or documented in this report.
On December 18, 2025, the inspectors presented the integrated inspection results to Tim Peter, Site Vice President, and other members of the licensee staff.
On July 18, 2025, the inspectors presented the radioactive gaseous and liquid effluent treatment inspection results to Carl Crawford, Plant Manager, and other members of the licensee staff.
8 DOCUMENTS REVIEWED Inspection Procedure Type Designation Description or Title Revision or Date 71111.04 Procedures N1-OP-14 Containment Spray System 048 N1-OP-45 Emergency Diesel Generators 052 N2-OP Lineups Reactor Core Isolation Cooling - Lineups 002 71111.05 Fire Plans N2-FPI-PFP-0201 Unit 2 Pre-Fire Plans 07 71111.06 Corrective Action Documents Resulting from Inspection 04900011 71111.11Q Procedures N1-PM-@004 Channel Interference Testing 0700 NF-AB-431 Power Suppression Testing 9
71111.12 Corrective Action Documents 04780032 04798318 04858274 04865553 Corrective Action Documents Resulting from Inspection 04898676 Miscellaneous 00700830 01381735 01466410 01490079 Purchase Order Packages 01263 Procurement Requirement Evaluation Form for Capacitor, Aluminum Electrolytic 82 Procedures N1-ISP-092-343 Local Power Range Monitoring Calibration Channel 13 006 Work Orders C93760312 C93991129 71111.13 Corrective Action Documents 04900315 Miscellaneous RICT Record for TS LCO 3.3.6.1 Entered July 18, 2025
9 Inspection Procedure Type Designation Description or Title Revision or Date Procedures ER-N2-600-2001 Nine Mile Point Unit 2 RICT System Guidelines 1
OP-AA-108-118 Risk Informed Completion Time 3
71111.15 Corrective Action Documents 04868710 04880832 04886669 04893961 Engineering Changes 644967 Biasing of the 2LDS*TRSH1C Yokogawa to Account for Channel Inaccuracy 000 CC-AA-112-F-03 Temporary Configuration Change Installation and Removal Authorizations 002 71111.24 Corrective Action Documents 04777743 04881129 04900315 Procedures N2-ISP-ISC-Q004 Quarterly Functional Test and Trip Calibration of ECCS Actuation on Reactor Vessel Low Low Low Level 1 and RCIC Actuation on Reactor Vessel Low Low Level 2 and High Level 8 007 N2-OSP-RHS-Q@005 RHR System Loop B Pump and Valve Operability Test 016 S-PM-003 BDB-GENA, FLEX Portable Diesel Generator A, Test 008 Work Orders 05727789 C93960403 C93983710 71151 Miscellaneous NEI 99-02 Regulatory Assessment Performance Indicator Guideline 7