IR 05000237/2025001
| ML25127A001 | |
| Person / Time | |
|---|---|
| Site: | 05000236, Dresden |
| Issue date: | 05/08/2025 |
| From: | Robert Ruiz NRC/RGN-III/DORS/RPB1 |
| To: | Rhoades D Constellation Energy Generation |
| Shared Package | |
| ML24312A374 | List: |
| References | |
| IR 2025001 | |
| Download: ML25127A001 (1) | |
Text
SUBJECT:
DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 - INTEGRATED INSPECTION REPORT 05000237/2025001; 05000249/2025001 AND 07200037/2025001
Dear David Rhoades:
On March 31, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Dresden Nuclear Power Station, Units 2 and 3. On April 15, 2025, the NRC inspectors discussed the results of this inspection with H. Patel, Plant Manager, and other members of your staff. The results of this inspection are documented in the enclosed report.
No NRC-identified or self-revealing findings were identified during this inspection.
A licensee-identified violation which was determined to be of very low safety significance is documented in this report. We are treating this violation as a non-cited violation (NCV)
consistent with Section 2.3.2 of the Enforcement Policy.
If you contest the violation or the significance or severity of the violation documented in this inspection report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region III; the Director, Office of Enforcement; and the NRC Resident Inspector at Dresden Nuclear Power Station, Units 2 and 3.
May 8, 2025 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 Ruiz, Chief Reactor Projects Branch 1 Division of Operating Reactor Safety Docket Nos. 05000237; 05000249 and 07200037 License Nos. DPR-19 and DPR-25
Enclosure:
As stated
Inspection Report
Docket Numbers:
05000237; 05000249 and 07200037
License Numbers:
Report Numbers:
05000237/2025001; 05000249/2025001 and 07200037/2025001
Enterprise Identifier:
I-2025-001-0064 and I-2025-001-0082
Licensee:
Constellation Energy Generation, LLC
Facility:
Dresden Nuclear Power Station, Units 2 and 3
Location:
Morris, IL
Inspection Dates:
January 01, 2025 to March 31, 2025
Inspectors:
N. Audia, Reactor Inspector
B. Lin, Senior Health Physicist
J. Meszaros, Resident Inspector
M. Porfirio, Illinois Emergency Management Agency
C. St. Peters, Senior Project Engineer
J. Steffes, Senior Resident Inspector
Approved By:
Robert Ruiz, Chief
Reactor Projects Branch 1
Division of Operating Reactor Safety
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Dresden Nuclear 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. A licensee-identified non-cited violation is documented in report section: 71152
List of Findings and Violations
No findings or violations of more than minor significance were identified.
Additional Tracking Items
None.
PLANT STATUS
Unit 2 began the inspection period at rated thermal power. On March 7, 2025, power was reduced to approximately 80 percent to perform control rod recovery following scram valve maintenance. The unit returned to rated thermal power the next day. On March 21, 2025, power was reduced to approximately 55 percent to perform scram valve maintenance, rod sequence exchange and 2D condensate/condensate booster pump maintenance. The unit returned to rated thermal power on March 23, 2025, and remained at or near rated thermal power for the remainder of the inspection period.
Unit 3 began the inspection period at rated thermal power. On February 26, 2025, power was reduced to approximately 32 percent to troubleshoot and correct a drywell pneumatic leak and perform rod sequence exchange. The unit was returned to rated thermal power on February 28, 2025, and remained at or near rated thermal power for the remainder 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
71111.01 - Adverse Weather Protection
Seasonal Extreme Weather Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated readiness for seasonal extreme weather conditions prior to the onset of seasonal cold temperatures for the following systems:
Standby liquid control, station batteries, and emergency diesel generators, on January 6 - 10, 2025
Impending Severe Weather Sample (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated the adequacy of the overall preparations to protect risk-significant systems from impending severe weather of high winds and possible tornadic activity on March 14, 2025.
71111.04 - Equipment Alignment
Partial Walkdown Sample (IP Section 03.01) (4 Samples)
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
- (1) Unit 2 standby liquid control system on January 6, 2025
- (2) Unit 2 standby diesel generator system on January 8, 2025
- (3) Unit 3 isolation condenser on January 23 - 30, 2025
- (4) Unit 2 isolation condenser during high pressure core injection work window on March 26-27, 2025
71111.05 - Fire Protection
Fire Area Walkdown and Inspection Sample (IP Section 03.01) (3 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) Fire zone (FZ) 7.0 B, Unit 3 battery room elevation 551', and FZ 6.1, Unit 3 250V battery charger room elevation 538', on January 3, 2025
- (2) FZ 11.2.1, Unit 2 southwest corner room elevation 476', on January 14, 2025
- (3) FZ 6.2, Unit 2/3 comp room and auxiliary electrical room elevation 517', on January 31, 2025
Fire Brigade Drill Performance Sample (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated the onsite fire brigade training and performance during an announced fire drill on February 7, 2025.
71111.07A - Heat Exchanger/Sink Performance
Annual Review (IP Section 03.01) (1 Sample)
The inspectors evaluated readiness and performance of:
- (1) Unit 3 "B" reactor building closed cooling water system heat exchanger
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 the Unit 3 planned downpower and subsequent power ascension due to a drywell pneumatic leak on the 1A MSIV on February 26, 2025 and February 28th, 2025.
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed and evaluated licensed crew performance in the main control room simulator on January 24, 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 (SSCs) remain capable of performing their intended function:
- (1) Drywell continuous air monitor system, due to failures
- (2) Maintenance rule periodic 10CFR50.65 (a)(3) assessment Quality Control (IP Section 03.02) (1 Partial)
The inspectors evaluated the effectiveness of maintenance and quality control activities to ensure the following SSC remains capable of performing its intended function:
(1)
(Partial)
Unit 2 high pressure coolant injection booster pump fitting repair per Work Order (WO) 5540836
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) Unit 2 plant risk review and management action implementation associated with action green and blue fire risks due to planned maintenance on the high pressure coolant injection system on March 25-27, 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) (1 Sample)
- (1) Post-maintenance testing followed planned maintenance on the 3C shutdown cooling breaker, per WO 4598872
Surveillance Testing (IP Section 03.01) (2 Samples)
- (1) DIS 0250-02, Main Steam Line Low Pressure Isolation Switch Calibration (Reactor Mode Switch in Run Position), on January 17, 2025
- (2) Unit 3 division 2 core spray logic system function test per WO 5350913 on March 20-21, 2025
Inservice Testing (IST) (IP Section 03.01) (2 Samples)
- (1) Unit 2 diesel generator cooling water pump test per WO 5615641
- (2) Unit 2A standby liquid control pump surveillance per WO 5619671
71114.06 - Drill Evaluation
Additional Drill and/or Training Evolution (2 Samples)
The inspectors evaluated:
- (1) Focus area drill on January 30, 2025
- (2) Focus area drill on February 4,
OTHER ACTIVITIES - BASELINE
71152A - Annual Follow-up Problem Identification and Resolution Annual Follow-up of Selected Issues (Section 03.03)
The inspectors reviewed the licensees implementation of its corrective action program related to the following issues:
- (1) Evaluation and corrective actions for the discolored and contaminated oil, as documented in Action Request (AR) 4790335 and AR
OTHER ACTIVITIES
- TEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL
60855 - Operation of An ISFSI Operation of An ISFSI
- (1) The inspectors evaluated the licensee's independent spent fuel storage installation (ISFSI) cask loading activities from March 17 through March 21, 2025. Specifically, the inspectors observed the following activities during the loading of Multi-Purpose Canister (MPC) No. 840:
- heavy load movement of loaded MPC out of the spent fuel pool
- canister blowdown
- forced helium dehydration
- closure welding and non-destructive evaluations
- radiological field surveys The inspectors performed walkdowns of the ISFSI pads and haul path, which also included performing independent radiation surveys.
The inspectors evaluated the following:
- spent fuel selected for loading into dry cask storage during this loading campaign
- selected corrective action program documents
- selected 72.48 screenings and evaluations
- changes to the site's 10 CFR 72.212 report since the previous inspection
INSPECTION RESULTS
Licensee-Identified Non-Cited Violation 71152A This violation of very low safety significance was identified by the licensee and has been entered into the licensee corrective action program and is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Violation: Technical Specification Section 5.4.1.a. requires, in part, that written procedures shall be established, implemented, and maintained covering the applicable procedures recommended in Regulatory Guide 1.33, Revision 2, Appendix A, February 1978.
NRC Regulatory Guide 1.33, Revision 2, Appendix A, Section 9 addresses Procedures for Performing Maintenance and Section 9.a, addresses maintenance that can affect the performance of safety-related equipment should be properly preplanned and performed in accordance with written procedures, documented instructions, or drawings appropriate to the circumstances.
The licensee established Procedure MA-AA-716-006, Control of Lubrication Program, Revision 16, to address instructions for the storage, control, use and disposal of lubricants, and provides guidance for oil sampling and analysis. Procedure MA-AA-716-006, Control of Lubrication Program, Revision 16, Step 4.4.3 requires "STORE radiologically clean waste oils/greases in designated containers in appropriate storage rooms, (or other area directed),for proper disposal at some later date.
Contrary to the above, prior to May 14, 2024, to January 17, 2025, the licensee failed to implement Step 4.4.3 of procedure MA-AA-716-006, Control of Lubrication Program, Revision 16. Specifically, the licensee did not implement the proper storage of lubricants as outlined in MA-AA-716-006, allowing the drum of Mobil DTE 746 to become contaminated with a non-similar oil type and was later added to the upper reservoir for the 2D low pressure coolant injection (LPCI) motor, a safety related component.
Significance/Severity: Green. The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. Using Exhibit 2, Mitigating Systems Screening Questions, the inspectors answered "NO" to questions A.1. through A.6, and determined that the finding was of very low safety significance (Green).
Corrective Action References: AR 4790335, Mobil DTE 746 Oil Drum - Discolored Oil AR 4792117, Mobil DTE 746 Oil Drum - Discolored Oil (F/U to IR 04790335 AR 4829285, 2D LPCI Motor-Abnormal Oil Samples (F/U to IR 04792117)
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On April 15, 2025, the inspectors presented the integrated inspection results to H. Patel, Plant Manager, and other members of the licensee staff.
- On March 31, 2025, the inspectors presented the ISFSI cask loading inspection results to H. Patel, Plant Manager, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
DR-0-25-00205
Combined ALARA Plan/Micro-ALARA Plan
2/06/2025
ALARA Plans
ALARA Work-In-Progress Review
03/21/2025
4500105
NOS ID: HI-Storm Move Sheet for 2020
05/16/2022
4500125
22 ISFSI NRC Inspection-HI-STAR Cask Degraded
Areas
05/16/2022
4501575
22 Dry Cask Cask #2 Completion
05/23/2022
4777107
Soft Deposits on HI-Storm 100-010
05/29/2024
Corrective Action
Documents
4810843
Work Request for Leak Test of HI-TRAC
10/21/2024
Corrective Action
Documents
Resulting from
Inspection
4846657
NRC ID: 2025 Dresden FSP Typographical Error
03/18/2025
Engineering
Changes
DRE25-0001
Dresden Unit 2 Fuel Selection Packages and Alternate
Assembly List for the 2025 SFLC - ISFSI
2.48-755
Radiological and Licensing DCR for South ISFSI Expansion
Pad
2.48-775
Dry Cask Storage/ISFSI Inspection Surveillance Program
2.48-777
Implementation of Holtec ECO No. 5014-312 R0 for Storage
of Select Foreign Materials in the HI-STORM 100 System via
2.212 Change Requests 22-01 R0 and 22-02 R0
2.48-792
Holtec Independent Spent Fuel Storage Installation (ISFSI)
Radiation Survey
Miscellaneous
2.48-801
Spent Fuel Casks for the 2025 Loading Campaign (Dresden
21227-840-04
Canister Lid to Shell
03/21/2025
21227-840-05
Canister Lid to Drain Port Cover with Setscrews
03/21/2025
21227-840-06
Canister Lid to Vent Port Cover with Setscrews
03/21/2025
NDE Reports
21227-840-07
Canister Shell and Lid to Closure Rings
03/21/2025
Quality Assurance Manual
GQP-9.6
Visual Examination of Welds
60855
Procedures
Constellation 72.48 Review Process
MA-DR-MM-4-
58904
Dry Cask Storage Special Lifting Device Inspection/Testing
MA-DR-MM-5-
58003
Visual Inspection and Preventive Maintenance of Unit 1, Unit
2, Unit 3, and Unit 2-3 Overhead and Gantry Cranes
Fuel Characterization for Dry Storage
Quality Assurance Topical Report
Procedures
OU-MW-671-200
MPC Processing Forced Helium Dehydration (FHD) for
24-215149
Radiological Survey of East ISFSI Pad
04/10/2024
24-218725
Radiological Survey of West ISFSI Pad
06/04/2024
Radiation
Surveys
25-236614
Radiological Survey of Cask Pad
03/17/2025
Self-Assessments NOSA-DRE-22-
Independent Spent Fuel Storage Installation Audit Report
05/25/2022
4946090-01
D2/3 3Y COM ISFSI Integrity Surveillance
08/02/2022
24566-01
EWP EM D2/3 1Y COM OSHA Insp Crane - Rx Bldg
Overhead
2/14/2025
24566-02
EWP EM D2/3 1Y COM OSHA Insp Crane - Festoon
Inspection
2/14/2025
60855
Work Orders
24567-01
MM D2/3 1Y COM Reactor Building Overhead Crane Inspctn
2/15/2025
26954
SBLC 3B Relief Valve Line Heat Trace Not Completely on
Pipe
01/07/2025
28014
NRC Questions from Plant Walkdown
01/07/2025
Corrective Action
Documents
Resulting from
Inspection
4845456
NRC Identified Missile Hazards
03/14/2025
Miscellaneous
Certification of 2024-25 Winter Readiness
11/15/2024
DOA 0010-02
Tornado Warning/Severe Winds
DOA5700-01
Loss of Heating Boilers
DOS 0010-22
Preparation for Cold Weather Operations for Unit 2
DOS 0010-25
Preparation for Cold Weather Operations for Unit 3
OP-AA-108-111-
1001
Severe Weather and Natural Disaster Guidelines
OP-DR-108-111-
1004
Cold Weather Strategy
Procedures
OP-DR-108-111-
1006
Intake Blockage Station Response
Drawings
M-173
Diagram of Corrosion Test Diesel Start-up Air Piping
BJ
M-22
Diagram of Service Water Piping
M-28
Diagram of Isolation Condenser Piping
M-33
Diagram of Standby Liquid Control Piping
IB
M-359
Diagram of Isolation Condenser Piping
BR
M-40
Diagram of Turbine Building Equipment Drains and Diesel
Air Intake And Exhaust
ZN
M-41
Diagram of Turbine and Diesel Oil Piping
AI
M-478
Diagram of Diesel Generator Lube Oil Piping
J
M-517
Diesel Generator Engine Cooling Water System
I
M-518
Diesel Generator Fuel Oil System
F
M-974
Diagram of Diesel Generator Room Ventilation
L
DOP 1100-01
Standby Operation of Standby Liquid Control System
DOP 1100-M1
Unit 2 Standby Liquid Control System Checklist
DOP 1300-M1/E1
Unit 3 Isolation Condenser System Checklist
DOP 1300-M1/E1
Unit 2 Isolation Condenser System Checklist
DOP 6600-01
Diesel Generator 2 Preparation for Standby Operation
Procedures
DOP 6600-M1
Unit 2 Standby Diesel Generator
Calculations
DRE97-0105
Determination of Combustible Loading
Corrective Action
Documents
4835485
4.0 Critique Crew 5 Q1 Announced Fire Drill
2/07/2025
100 Prefire Plan
Master Legend
Dresden Generating Station Pre-Fire Plan
2 U2RB-2
FZ 11.2.1 Unit 2 Southwest Corner Room Eleve. 476'
143 U2TB-46
FZ 6.2 Unit 2/3 Comp Room & Auxiliary Electrical Room
Elev. 517
169 U3TB-79
FZ 7.0 B Unit 3 Battery Room Elev. 551'
Fire Plans
169 U3TB-80
FZ 6.1 Unit 3 250V Battery Charger Room Elev. 538'
DR-PSA-021.11
Dresden Fire PRA Summary & Quantification Notebook
Miscellaneous
Fire Drill Scenario
25-01
U3 RB 3B Pump Back Compressor Fire
2/04/2025
NDE Reports
3B RBCCW EDDY CURRENT EXAMINATION FINAL
REPORT
01/2025
Procedures
DTP 75
Heat Exchanger Inspection Program
Work Orders
20289
D3 QTR COM REVIEW OF RBCCW OPERATIONAL
TREND DATA
2/21/2024
5499196
D3 QTR COM REVIEW OF RBCCW OPERATIONAL
TREND DATA
05/29/2024
5544001
D3 QTR COM REVIEW OF RBCCW OPERATIONAL
TREND DATA
08/21/2024
OBE 25-01A
LORT Scenario
Miscellaneous
ReMA Plan D329-005 Unit 3 Shutdown
Procedures
Conduct of Simulator Training and Evaluation
4540536
MRULE A1 Determinations Performed Incorrectly
2/02/2022
4793017
U2 Drywell CAM Inoperable
08/09/2024
4796424
Unit 2 Drywell CAM Low Flow Issue
08/23/2024
4796772
Potential Trend IR: Unit 2 Drywell CAM Equipment Failure
08/26/2024
4812159
10/25/2024
4819082
TRM 3.4.d - 30d Clock Exceeded for U2 DW CAM INOP
11/21/2024
4819869
U2 Drywell CAM Flow Indicator Light is Red
11/26/2024
24283
U2 Drywell CAM Deemed Inoperable due to Flow Issue
2/17/2024
Corrective Action
Documents
4830977
Unit 2 CAM is OOS due to High Flow
01/19/2025
Maintenance Rule Periodic Assessment #15 (10CFR50.65
(a)(3) Assessment)
10/01/2022-
09/30/2024
Miscellaneous
Maintenance Rule (a)(1) Status Report
2/06/2025
Maintenance Rule Implementation Per NEI 18-10
Procedures
Maintenance Rule 18-10 - Periodic (a)(3) Assessment
Work Orders
5084827-01
NMC Drywell Continuous Air Monitor Preventive
Maintenance and Calibration
11/24/2024
Protected Equipment List
03/25/2025
OP-DR-108-117-
1001
Protected Equipment and Pathway Policy
Procedures
On-line Risk Management and Assessment
Procedures
DOS 1100-04
Standby Liquid Control System Quarterly/Comprehensive
Pump Test for the Inservice Testing Program
0607027-03
EM EWP Perform Receipt Inspection on 4KV Bkr UTC
0000873998
01/07/2025
4598872
D3 8Y PM 4KV CUB INSP BUS 34-1 CUB 14; 3C SDC PMP
01/14/2025
5396420
TS MSL Lo Press Including Time Delay Relay Cal
01/17/2025
Work Orders
5598901
EM Swap 4KV Bkr Bus 34-1, Cubicle 14 (UTC 0000873998)
01/16/2025
1Q2025 FAD
Focus Area Drill
2/04/2025
Miscellaneous
1Q2025FAD
Focus Area Drill
01/30/2025
4790335
Mobile DTE 746 Oil Drum - Discolored Oil
07/29/2024
4792117
Mobil DTE 746 Oil Drum - Contaminated (F/U to IR
04790335)
08/06/2024
Corrective Action
Documents
29285
2D LPCI Motor - Abnormal Oil Samples (F/U to IR
04792117)
01/13/2025
Miscellaneous
VETIP Binder #:
D1995
General Electric Tri-Clad Vertical Induction Motors
DOS 0040-02
Operator Oil Sampling for Offsite Laboratory Analysis
160
Control of Lubricants Program
MA-AA-716-230-
1001
Oil Analysis Interpretation Guideline
Procedures
MA-AA-716-230-
1004
Lubricant Sampling Guideline
Work Orders
5160690-01
EM EWP 4Q EQ 2D LPCI PMP MOTOR E.Q. SURV
05/14/2024