IR 05000237/2025004
| ML26043A331 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 02/12/2026 |
| From: | Robert Ruiz NRC/RGN-III/DORS/RPB1 |
| To: | Mudrick C Constellation Energy Generation, Constellation Nuclear |
| References | |
| IR 2025004 | |
| Download: ML26043A331 (0) | |
Text
SUBJECT:
DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 - INTEGRATED INSPECTION REPORT 05000237/2025004 AND 05000249/2025004
Dear Christopher H. Mudrick:
On December 31, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Dresden Nuclear Power Station, Units 2 and 3. On February 3, 2026, the NRC inspectors discussed the results of this inspection with H. Patel, Site Vice President, and other members of your staff. The results of this inspection are documented in the enclosed report.
One finding of very low safety significance (Green) is documented in this report. This finding involved a violation of NRC requirements. 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.
If you disagree with a cross-cutting aspect assignment in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your disagreement, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region III; and the NRC Resident Inspector at Dresden Nuclear Power Station, Units 2 and 3.
February 12, 2026 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 and 05000249 License Nos. DPR-19 and DPR-25 Enclosure:
As stated cc w/ encl: Distribution via GovDelivery Signed by Ruiz, Robert on 02/12/26
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.
List of Findings and Violations
Impaired Fire Door Without Authorized Plant Barrier Impairment Permit Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000237,05000249/2025004-01 Open/Closed
[H.12] - Avoid Complacency 71111.05 The inspectors identified a finding of very low safety significance (Green) and an associated Non-cited Violation (NVC) of Technical Specifications 5.4.1.c, Fire Protection Program Implementation, for the licensees failure to implement procedures associated with fire barriers. Specifically, the licensee failed to evaluate impairment of a fire door prior to blocking its ability to close during the most recent Dresden Unit 2 refueling outage.
Additional Tracking Items
None.
PLANT STATUS
Unit 2 The unit began the inspection period at full rated thermal power. On October 1, 2025, the unit was downpowered to approximately 70 percent to address a degraded condition in the feedwater system. The unit returned to full rated thermal power on the same day where it remained with the exception of short-term power reductions for control rod sequence exchanges, testing, and as requested by the transmission system operator.
Unit 3 The unit began the inspection period in coastdown. On October 26, 2025, the unit was shut down to commence refueling outage (RFO) D2R29. The unit was started up on November 17, 2025, and commenced power ascension. The unit returned to full rated thermal power on November 22, 2025, where it remained with the exception of short-term power reductions for control rod sequence exchanges, testing, and as requested by the transmission system operator.
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 2 Containment Cooling Service Water on October 30, 2025.
- (2) Unit 3 Division II Containment Cooling Service Water on December 4, 2025, after emergent repairs to address a thru-wall pipe leak.
Complete Walkdown Sample (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated system configurations during a complete walkdown of the Unit 2 Standby Liquid Control system on October 8, 2025.
71111.05 - Fire Protection
Fire Area Walkdown and Inspection Sample (IP Section 03.01) (6 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) 8.2.6.A, Turbine Building-Mezzanine Elevations 534' 0 and 538 ' 0,"
on October 21, 2025
- (2) FZ 1.1.1.2, U3 Reactor Building Ground Floor, Elevation 517,' on October 31, 2025
- (3) FZ 8.2.5A, Unit 3 H.P. Heaters/Steam Lines ELEV. 517', on November 5, 2025
- (4) FZ 8.2.2.B, Unit 3 CCSW [Containment Cooling Service Water (CCSW)] Pumps ELEV. 495', on November 7, 2025
- (5) Unit 2 low pressure heater bay basement under condenser hotwell on November 13, 2025
- (6) FZ 1.1.2.3, Unit 2 Reactor Building General Area 545', on November 20, 2025
71111.12 - Maintenance Effectiveness
Maintenance Effectiveness (IP Section 03.01) (1 Sample)
The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components (SSCs) remain capable of performing their intended function:
- (1) Common 2/3 A Isocondenser Makeup Pump failed to start on December 22, 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) Work week risk for the work week of 10/20/25 on October 20, 2025
- (2) Unit 3 online risk action Green, fire risk blue during Unit 2 reserve auxiliary transformer out of service on November 3, 2025
- (3) Work week risk for the week of 11/17/25 on November 17, 2025
- (4) Work week risk for the week of 11/24/25 on November 19, 2025
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (3 Samples)
The inspectors evaluated the licensees justifications and actions associated with the following operability determinations and functionality assessments:
- (1) Action Request (AR) 4808629, 3C LPCI [Low Pressure Coolant Injection] Pump Discharge Pressure, on October 1, 2025
- (2) AR 4899538, Multiple Unexpected Alarms During B.5.b.run, on October 1, 2025
- (3) AR 4904070, 2A RB [Reactor Building] vent fan failed to trip, on October 9, 2025
71111.18 - Plant Modifications
Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02) (2 Samples)
The inspectors evaluated the following temporary or permanent modifications:
- (1) Engineering Change (EC) 634420, Add Throttle Valve to SW Pipe To Reduce Its Pressure To Match CCSW Pressure and Flow in Line to the ECCS [Emergency Core Cooling System (ECCS)] Room Coolers, on October 14, 2025
71111.20 - Refueling and Other Outage Activities
Refueling/Other Outage Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated D2R29 activities from October 28, 2025, to November 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) (8 Samples)
- (1) Post-Maintenance Testing (PMT) following annual preventative maintenance on the #1 B5B Pump on October 1, 2025.
- (2) PMT following corrective work to repair a through wall leak on Unit 2 CCSW piping line 2-1510-16" under Work Order (WO) 05724930 on October 2, 2025
- (3) PMT following corrective work to repair the Unit 2 B medium range Reactor Coolant System (RCS) control room level indication on October 4, 2025.
- (4) PMT following correction of a wiring discrepancy on Unit 2 reactor protection system on November 6, 2025.
- (5) PMT following corrective maintenance on main steam isolation valve 2-0203-2B under WO 04661461 on November 10, 2025
- (6) PMT following corrective maintenance on feedwater check valve 2-0220-58A under WO 05014734 on November 12, 2025
- (7) PMT of the Unit 2 standby liquid control system following squib valve replacement on November 13, 2025.
- (8) Hydrostatic testing of the reactor vessel system on November 15, 2025.
Surveillance Testing (IP Section 03.01) (3 Samples)
(1)2/3 Emergency Diesel Generator Safety Related Contact Testing per DES 6600-03 on October 3 2025
- (2) Unit 2 Isolation Condenser heat removal capability test per DOS 1300-01 on October 23, 2025.
- (3) Unit 2, Division 2 bus undervoltage and emergency core cooling system integrated functional test per DOS 6600-05 on October 30, 2025.
Containment Isolation Valve (CIV) Testing (IP Section 03.01) (1 Sample)
- (1) Local leak rate testing of inboard feedwater check valve 220-58B on October 29, 2025.
71114.04 - Emergency Action Level and Emergency Plan Changes
Inspection Review (IP Section 02.01-02.03) (1 Sample)
- (1) The inspectors evaluated the following submitted Emergency Action Level and Emergency Plan changes.
- EP-AA-1000, Standardized Radiological Emergency Plan, Revision 34 This evaluation does not constitute NRC approval.
RADIATION SAFETY
71124.03 - In-Plant Airborne Radioactivity Control and Mitigation
Permanent Ventilation Systems (IP Section 03.01) (1 Sample)
The inspectors evaluated the configuration of the following permanently installed ventilation systems:
Temporary Ventilation Systems (IP Section 03.02) (1 Sample)
The inspectors evaluated the configuration of the following temporary ventilation systems:
- (1) Respirator mask washer and dryer ventilation portable HEPA unit
Self-Contained Breathing Apparatus for Emergency Use (IP Section 03.04) (1 Sample)
- (1) The inspectors evaluated the licensees use and maintenance of self-contained breathing apparatuses.
71124.04 - Occupational Dose Assessment
Source Term Characterization (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated licensee performance as it pertains to radioactive source term characterization.
External Dosimetry (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated how the licensee processes, stores, and uses external dosimetry.
Internal Dosimetry (IP Section 03.03) (1 Sample)
The inspectors evaluated the following internal dose assessments:
- (1) Whole body counts to investigate if an intake occurred after a personnel contamination event
Special Dosimetric Situations (IP Section 03.04) (1 Sample)
The inspectors evaluated the following special dosimetric situations:
- (1) Declared pregnant workers
OTHER ACTIVITIES - BASELINE
71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
MS05: Safety System Functional Failures (SSFFs) Sample (IP Section 02.04) (2 Samples)
- (1) Unit 2 (October 1, 2024, through September 30, 2025)
- (2) Unit 3 (October 1, 2024, through September 30, 2025)
BI01: Reactor Coolant System (RCS) Specific Activity Sample (IP Section 02.10) (2 Samples)
- (1) Unit 2 (July 1, 2024, through November 30, 2025)
- (2) Unit 3 (July 1, 2024, through November 30, 2025)
OR01: Occupational Exposure Control Effectiveness Sample (IP Section 02.15) (1 Sample)
- (1) July 1, 2024, through November 30, 2025 PR01: Radiological Effluent Technical Specifications/Offsite Dose Calculation Manual Radiological Effluent Occurrences (RETS/ODCM) Radiological Effluent Occurrences Sample (IP Section 02.16) (1 Sample)
- (1) July 1, 2024, through November 30, 2025
71153 - Follow-Up of Events and Notices of Enforcement Discretion Event Follow-up (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated a service water rupture and licensees response on November 5, 2025
Personnel Performance (IP Section 03.03) (1 Sample)
- (1) The inspectors evaluated drop of a double blade guide in the Unit 3 pool and licensees performance on October 8, 2025.
INSPECTION RESULTS
Impaired Fire Door Without Authorized Plant Barrier Impairment Permit Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000237,05000249/2025004-01 Open/Closed
[H.12] - Avoid Complacency 71111.05 The inspectors identified a finding of very low safety significance (Green) and an associated Non-cited Violation (NVC) of Technical Specifications 5.4.1.c, Fire Protection Program Implementation, for the licensees failure to implement procedures associated with fire barriers. Specifically, the licensee failed to evaluate impairment of a fire door prior to blocking its ability to close during the most recent Dresden Unit 2 refueling outage.
Description:
On October 28, 2025, the inspectors identified that a fire door allowing access between the ground floors of the Dresden Unit 2 and Unit 3 reactor buildings was blocked by temporary cabling. This rolling fire door, 2/3-4100-57, is normally open and is actuated to close via a fusible link to prevent a fire from spreading between the two buildings. Should a fire propagate through this door, it could impact equipment credited in either units safe shutdown analysis.
The fire door is clearly marked with red paint and the words Fire Door, Do Not Block.
Procedure DFPP 4175-01, Rev. 25, Fire Barrier Integrity and Maintenance Step G.4.a directs that fire doors must not be blocked open by props or any other material in its closing path. Hoses, ropes, cabling, etc. running through a fire door opening could prevent the door from closing as designed during a fire. Although CC-AA-201, Rev. 14, Plant Barrier Control Program can be used to authorize temporary activities that prevent the immediate closure of a fire door, it requires the approval of a plant barrier impairment (PBI) permit evaluating the activity and proposing compensatory actions before the door is blocked. The licensee did not authorize a PBI prior to blocking this door.
Corrective Actions:
Once notified of the impaired fire door, the licensee entered the required actions of Technical Requirements Manual (TRM) 3.7.n for an inoperable fire rated assembly and removed the cables to restore functionality of the fire door prior to exiting TRM 3.7.n.
Corrective Action References: AR 4910486
Performance Assessment:
Performance Deficiency:
The licensees failure to authorize a PBI permit prior to impairment of fire door 2/3-4100-57 was contrary to Technical Specification 5.4.1.c, Fire Protection Program Implementation, and was a performance deficiency.
Screening:
The inspectors determined the performance deficiency was more-than-minor because it was associated with the Protection Against External Factors attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the impairment of fire door 2/3-4100-57 prevented it from closing as designed which impacted equipment credited in the sites safe shutdown analysis during a fire in either units reactor building.
Significance:
The inspectors assessed the significance of the finding using IMC 0609 Appendix F, Fire Protection Significance Determination Process. The inspectors reviewed Table 1.2.1 of IMC 0609 Appendix F and assigned a finding category of fire confinement because said finding is related to the impairment of a fire door. The inspectors next determined this issue had a high degradation rating in accordance with Section 02.03.05 of IMC 0609, Appendix F, Attachment 2, Degradation Rating Guidance, dated January 1, 2025, because Door 2/3-4100-57 was propped fully open. The finding was determined to be of very low safety significance (Green) in accordance with IMC 0609, Appendix F, Step 1.4.4-A because the inspectors determined the degraded fire confinement element could continue to provide adequate fire endurance to prevent fire propagation given the combustible loading in the fire area of concern. Specifically, Section 06.01.04.04 of IMC 0308, Attachment 3, Appendix F, Technical Basis Fire Protection Significance Determination Process (Supplemental Guidance for Implementing IMC 0609, Appendix F) At Power Operations dated January 1, 2025, provides basis information for the screening criteria included in Step 1.4.4-A of IMC 0609, Appendix F. It indicates that a moderately degraded fire barrier can be screened to Green if the combustible loading in the area of concern is consistent with that analyzed in the approved fire protection program. The inspectors reviewed combustible loadings documented for the reactor buildings in the licensees combustible loading calculation and combustible loading permits active at the time of the finding and determined that combustible loadings in the area of concern were consistent with that analyzed in the approved fire protection program, as such, the finding screened to Green.
Cross-Cutting Aspect:
H.12 - Avoid Complacency: Individuals recognize and plan for the possibility of mistakes, latent issues, and inherent risk, even while expecting successful outcomes. Individuals implement appropriate error reduction tools. Specifically, on October 28, 2025, the licensee did not consider potential undesired consequences of their actions before cables were routed through Door 2/3-4100-57, which is clearly marked with red paint and the words Fire Door, Do Not Block.
Enforcement:
Violation:
Technical Specification Section 5.4.1.c requires, in part, that written procedures shall be established, implemented, and maintained covering fire protection program implementation.
The licensee established Procedure DFPP 4175-01, Rev. 25, Fire Barrier Integrity and Maintenance to outline policies regarding the proper maintenance of each type of fire barrier component. Procedure DFPP 4175-01, Rev. 25, Step G.4.a requires that fire doors must not be blocked open by props or any other material in its closing path. Hoses, ropes, cabling, etc.
running through a fire door opening could prevent the door from closing as designed during a fire. Further, the licensee established Procedure CC-AA-201, Rev. 14, Plant Barrier Control Program to provide guidance and clarification on actions necessary to evaluate and compensate for, in part, an impaired fire barrier. Procedure CC-AA-201, Rev. 14 Step 3.7.3 requires that activities such as placing hoses, cables, or ramps in the doorway which would prevent its immediate closure require an approved PBI permit.
Contrary to the above, on October 28, 2025, the licensee failed to implement Step G.4.a of DFPP 4175-01, Rev. 25. Specifically, Fire door 2/3-4100-57 was blocked open by cabling running through its closing path, preventing the door from closing as designed during a fire.
An approved PBI permit per CC-AA-201, Rev. 14, was not approved prior to blocking the door.
Enforcement Action:
This violation is being treated as a NCV, consistent with Section 2.3.2 of the Enforcement Policy.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On February 3, 2026, the inspectors presented the integrated inspection results to H. Patel, Site Vice President, and other members of the licensee staff.
- On December 10, 2025, the inspectors presented the emergency preparedness inspection results to A. Clements, Corporate Emergency Preparedness, and other members of the licensee staff.
- On January 16, 2026, the inspectors presented the radiation protection inspection results to J. Jaegers, Radiation Protection Manager and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Corrective Action
Documents
U2 SBLC A Relief Valve Leaks
11/11/2021
Corrective Action
Documents
U2 SBLC B Relief Valve Failed to Lift
11/11/2021
Corrective Action
Documents
Inactive Packing Leak on 2-1101-9A 2A SBLC Disch
Drain VLV
2/07/2024
Corrective Action
Documents
Inactive Packing Leak on 2-1101-9B 2B SBLC Disch
Drain VLV
2/07/2024
Drawings
M-29 Sh 2
Diagram of LP Coolant Injection Piping
BO
Drawings
M-33
Diagram of Standby Liquid Control Piping
IB
Drawings
M-360 sheet 1
Diagram of L.P. Coolant Injection System
Drawings
M-360 sheet 2
Diagram of L.P. Coolant Injection Piping
BO
Engineering
Evaluations
EC EVAL 373443
Evaluation of Leakage from Cylinder Head Covers on 2A
SBLC Pump
2/31/2008
Miscellaneous
Tagout: 02-15-
D2R29 Div 1 CCSW Loop Piping Replacement 2-1510-16"-D 10/21/2025
Miscellaneous
Tagout: 03-15-
Replace Div 2 CCSW Piping on Torus Catwalk
11/29/2025
Procedures
DOP 1100-01
Standby Operation of Standby Liquid Control System
Procedures
DOP 1100-M1
Unit 2 Standby Liquid Control System Checklist
Procedures
DOP 1500-M1
Unit 3 LPCI and Containment Cooling Valve Checklist
Work Orders
OPE D2 48M/RFL TS SYS I SLC Manually Init to Inj Demin
WTR
11/15/2023
Work Orders
OP D2 2RFL TS System II SLC Manually Init to Inj Demin W
11/13/2025
Work Orders
D2 2Y TS 2B SBLC PMP Comprehensive Test for IST
Surveillance
07/19/2025
Work Orders
OP D2 QTR TS 2A SBLC PMP Test for In-Service Testing
06/30/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Surv.
Corrective Action
Documents
Day IR per TRM 3.7.j for U2 Turbine South Sprinkler OOS
11/14/2025
Corrective Action
Documents
Resulting from
Inspection
IEMA ID - Fire Door Blocked
10/28/2025
Fire Plans
108 U2RB-7
FZ 1.1.2.3 Unit 2 Reactor Building General Area 545'
Fire Plans
20 U3RB-23
FZ 1.1.1.2, UNIT 3 RX GROUND FLOOR ELEV. 517
Fire Plans
138 U2TB-41
FZ 8.2.5.A, UNIT 2 H.P. HEATERS/STEAM LINES ELEV.
517
Fire Plans
149 U2TB-51
FZ 8.2.6A, Unit 2 Switchgear Area Elevation 534'
Fire Plans
158 U3TB-69
FZ 8.2.2.B, UNIT 3 CCSW PUMPS ELEV. 495
Procedures
DFPP 4175-01
Fire Barrier Integrity and Maintenance
Procedures
ER-DR-600-1069
Site List of High Risk Fire Areas
Corrective Action
Documents
2/3 A Iso Condenser Makeup Pump Failed to Start
10/24/2025
Corrective Action
Documents
IR 4908459 MRule Determination Required Actions
10/30/2025
Procedures
DOP 1300-09
Isolation Condenser Makeup Pump Local Operation
Procedures
Maintenance Rule - (a)(1) and (a)(2) Requirements
Corrective Action
Documents
Received U2 SBO Excitation HI/LO Alarm
11/23/2025
Corrective Action
Documents
Air Void Identified U3 HPCI Piping during 1M Periodic Check
11/25/2025
Corrective Action
Documents
U3CCSW Div II Leak
11/25/2025
Corrective Action
Documents
NRC Walkdown Concerns
11/04/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Resulting from
Inspection
Fire Plans
105 U2RB-5
FZ 1.1.2.2 Unit 2 Rx Ground Floor Elev. 517'
Fire Plans
143 U2TB-46
Unit 2/3 Comp Room & Auxiliary Electrical Room Elev. 517
Fire Plans
146 U2TB-49A
FZ 8.2.6.A Unit 2 CREVS
Fire Plans
147 U2TB-49
FZ 2.0 Main Control Room Elev. 534'
Fire Plans
151 U2TB-53
FZ 7.A.1/8.2.7 Unit 2 Battery Room Elev. 549'
Fire Plans
158 U3TB-69
Unit 3 CCSW Pumps Elev. 495'
Fire Plans
161 U3TB-72
Unit 3 Reactor Feed Pumps Elev. 517'
Fire Plans
163 U3TB-74
Unit 3 Cond. Transfer Pumps/Hallway Elev. 517'
Fire Plans
164 U3TB-75
Unit 3 Track Way Area Elev. 517'
Miscellaneous
Combustible Permit
1796
Unit 3 Elevation 517'-6," Fire Zone 8.2.5.E
10/02/2025
Procedures
Protected Equipment List for Unit 2 HPCI
10/23/2025
Procedures
OP-DR-201-012-
1001
Dresden On-Line Fire Risk Management
Corrective Action
Documents
2A RB Vent Fan Fail to Trip
04/12/2023
Corrective Action
Documents
3C LPCI PP Approaching Min Discharge Pressure on
Min Flow
09/13/2024
Corrective Action
Documents
3C LPCI Pump Discharge Pressure
10/11/2024
Corrective Action
Documents
PI 3-1540-15C Digital Indication Was Found OOT
05/20/2025
Corrective Action
Documents
Multiple Unexpected Alarms during B.5.b Run
09/21/2025
Corrective Action
Documents
2A RB Vent Fan Failed to Trip
10/08/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Corrective Action
Documents
D2/3B 24M SBGT Sys Auto-Actuation Test Complete Un-Sat
10/13/2025
Corrective Action
Documents
Resulting from
Inspection
NRC ID: Additional Degradation Noted on Computer Point
10/06/2025
Corrective Action
Documents
Resulting from
Inspection
IR 4899538 Funcitonal Basis Screening Review
01/07/2026
Drawings
Schematic Diagram Reactor Building Vent Exhaust Fans and
Radwaste HVAC
Drawings
2E-2400C Sh 1
Schematic Diagram Standby Gas Treatment System
AK
Drawings
2E-2400C Sh 2
Schematic Diagram Standby Gas Treatment System
Engineering
Changes
DR-27D-M-002 Dresden Station Blackout (SBO) Building
Ventilation Air Requirement
003
Procedures
DAN XL3, Device
84-06, Device 84-
3SBO 517 DG/DAY TK RM WATERFLOW
Procedures
DOP 6620-21
Unit 2(3) SBO Ventilation
Work Orders
IM 2/3 B 24M TS SBGT Sys Auto-Actuation Test
04/13/2023
Work Orders
IM 2/3A 24M TS SBGT Sys Auto-Actuation Test
04/01/2025
Work Orders
IM 2/3B 24M TS SBGT Sys Auto-Actuation Test
10/08/2025
Work Orders
OP D3 QTR TS LPCI System Pump IST
09/14/2025
Work Orders
OP D3 QTR TS LPCI System Pump IST
06/19/2025
Corrective Action
Documents
U3 CCSW Keepfill Pressure Low after ECCS clr Flow
Balancing
03/14/2025
Corrective Action
Documents
WO to Adjust 3-3999-251A to Improve U3 CCSW Keepfill
Press
05/29/2025
Corrective Action
CCSW Keepfill Pressure Step Change
08/07/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Documents
Corrective Action
Documents
Unexpected Alarms When Swapping RPS A to Reserve Feed 10/27/2025
Corrective Action
Documents
Resulting from
Inspection
NRC ID'd-50.59 Screening 2023-020 Question 2 is
Incomplete
2/17/2025
Corrective Action
Documents
Resulting from
Inspection
NRC ID: EC 634420 Modification Not Adequately Controlled
01/21/2026
Corrective Action
Documents
Resulting from
Inspection
EC 634420 Piping Calcs Not Completed
2/02/2026
Drawings
2E-2467, Sheet 1
Schematic Diagram Reactor Protection System Scram Valve
Solenoids & Miscellaneous Aux. Relays
AH
Drawings
M-22
Diagram of Service Water Piping
Drawings
M-355
Diagram of Service Water Piping
Drawings
M-360, Sheet 2
Diagram of L.P. Coolant Injection Piping
BO
Engineering
Changes
Containment Cooling Service Water (CCSW) System Water
Hammer Loss of Keepfill Analysis
05/22/2003
Engineering
Changes
ADD THROTTLE VALVE TO SW PIPE TO REDUCE ITS
PRESSURE TO MATCH CCSW PRESSURE AND FLOW IN
LINE TO THE ECCS ROOM COOLERS
000
Work Orders
Operations to Perform PMT Testing per EC 640190 Rev 1
11/6/2025
Corrective Action
Documents
D2R29 Primary Containment Coatings Inspection Results
11/08/2025
Engineering
Changes
D2R29 Containment Coating Evaluation Report for Trending
and Analyzing Unit 2 Coating Failures
000
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Engineering
Evaluations
DRE10-0001
Unqualified Coatings in Containment
000A
Engineering
Evaluations
DRE98-0018
ECCS Strainer Head Loss Estimates for Dresden Station
Units 2 and 3
004
Miscellaneous
ReMA Plan #D229-
27
Unit 2 Shutdown for D2R29
10/27/2025
Miscellaneous
Sequence ID: 2S.8
Control Rod Sequence Review and Approval Sheet D2C29
Procedures
DGP 02-01
Unit Shutdown
179
Procedures
DGP 02-03
Reactor Scram
21
Procedures
Reactor Disassembly
Corrective Action
Documents
Stop Work during DES 6600-03 Checklist C
10/03/2025
Corrective Action
Documents
D2R29 MSIV 2-0203-2B LLRT Exceeded T.S. Limit < 62.4
scfh
10/27/2025
Corrective Action
Documents
D2R29 2-0220-58B Infinite Leakage
10/29/2025
Corrective Action
Documents
Leak from HCU 38-31 DCV-123
11/10/2025
Corrective Action
Documents
D2R29 RCPB Class 1 System Leakage Test Results
11/12/2025
Corrective Action
Documents
U2 CRD G-10 (26-39) Has DCV Leak at HCU
11/12/2025
Corrective Action
Documents
AR 814892814892U2 Isolation Condenser Failed DOS 1300-01
09/07/2008
Engineering
Changes
2-1510-16" CCSW CODE AND OPERABILITY MIN WALL
THICKNESS FOR UT INSPECTION LOCATION 2CCSW71 /
000
Engineering
Changes
RPS Scram Contactor Solenoid Wiring-Field Wiring
Condition Inverted from as Designed
Engineering
INSTALL SOCKOLET ON 2-1510-16" D (ON BOTTOM AND
000
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Changes
BETWEEN SUPPORT M-1664 D-68 AND M-1164 D-104)
Procedures
D2R29 2-0220-58A Infinite Leakage
10/30/2025
Procedures
DOS 7000-02
Local Leak Rate Testing of Main Steam Isolation Valves
(Wet Test)
Procedures
DOS 7000-26
Local Leak Rate Testing of Unit 2(3) Feedwater System
Valves [2(3)-220-58A(B), 2(3)-220-62A(B)]
Procedures
ER-AA-335-015-
2013
VT-2 Visual Examination in Accordance with ASME 2013
Edition
Procedures
MA-MW-796-101
Welding, Brazing and Soldering Records
Procedures
Nuclear Oversight Independent Inspection Plan
Work Orders
5537671-07
OP PMT Standby Liquid Squib Valve B per DOS 1100-04
11/13/2025
Work Orders
U2 CCSW Div 1 Thru Wall Leak
09/18/2025
Work Orders
OP D2 24M TS Bus 24-1 UV and ECCS Integrated Func Test 11/07/2025
Work Orders
EM D2/3 2Y D/G SR Contact Test-Output Brkr Logic
Checklist A
10/01/2025
Work Orders
EM D2/3 2Y D/G SR Contact Test-Output Brkr Logic
Checklist C
10/03/2025
Work Orders
OPV Perform AF LLRT 0220-57B & 0220-62B FW CK DOS
7000-26
10/30/2025
Work Orders
OP D2 10Y TS Isolation Condenser Heat Removal Test
10/27/2025
Work Orders
OPB D2 RFL TS 1000 psi Reactor Vessel System Leakage
Test/hy
11/15/2025
Work Orders
OP PMT Pump Run B5B Pump #1 Dresden Generating
Station
10/03/2025
Work Orders
SBLC PMTs Required for Mode 2
11/13/2025
Work Orders
IM Replace LY 2-0263-154B
10/28/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Work Orders
IM TS&R 2B Medium Range MCR LI 2-263-100B
10/04/2025
Work Orders
EM Change Wiring (West Scram Sol Fuse Pnls) EC 640190
Rev. 1
11/06/2025
Work Orders
(OA) EM Change Wiring (East Scram Sol Fuse Pnls) EC 640190 Rev. 1
11/06/2025
Work Orders
Information for 2A RPS Troubleshooting (IR 4909285)- OPS
11/06/2025
Calculations
Evaluation No.: 24-
§50.54(q) Program Evaluation Assessment Review for
Standardized Radiological Emergency Plan Revision 34
2/28/2025
Miscellaneous
EPID L-2018-LLA-
0045
Issuance of Amendments to Revise the Emergency
Response Organization Staffing Requirements
03/21/2019
Procedures
Exelon Nuclear Standardized Radiological Emergency Plan
Procedures
Standardized Radiological Emergency Plan
Procedures
EPA-400/R-17/001
PAG Manual: Protective Action Guides and Planning
Guidance for Radiological Incidents
January 2017
Miscellaneous
0900e54e852943bc Posi3 USB Test Results Complete SCBA Test
2/28/2025
Miscellaneous
CGE
MSA G1 Monthly Inspections
04/25/2025
Miscellaneous
S1936.01
Quarterly Service Air and Self-Contained Breathing
Apparatus Air Quality Test
07/07/2025
Miscellaneous
Service Order
S053557
MSA G1 Repair and Flow Test
09/29/2025
Procedures
Controlled Negative Pressure (CNP) Fit Testing
Procedures
Monthly Inspection and Maintenance of the MSA G1
Self-Contained Breathing Apparatus (SCBA)
Procedures
RP-DR-832
Operation of the MAKO Air Compressor and the MAKO
Stationary Containment Fill Station (SCFS)
Work Orders
05404435
Standby Gas Treatment Charcoal Filter Iodine Removal
Efficiency Test
05/28/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Corrective Action
Documents
Unplanned Dose Rate Alarm
05/13/2025
Engineering
Evaluations
26 Prospective Dose Evaluation for Occupational Exposure 10/10/2025
Miscellaneous
Personnel Exposure Investigation Form
Various
Miscellaneous
Intake Investigation Form
11/01/2025
Miscellaneous
Declaration of Pregnancy
Various
Miscellaneous
Embryo/Fetus Dose Report
Various
Miscellaneous
RP-AA-605 CGE
CFR 61 Waste Stream Analysis - DAW 2025
11/16/2025
Procedures
Personnel Exposure Investigations
Procedures
Methods for Estimating Internal Exposure from In Vivo and In
Vitro Bioassay Data
Procedures
Prenatal Radiation Exposure
Radiation Surveys
Whole Body Count Analysis Report
11/01/2025
Radiation Surveys 2025-241082
Low Pressure Heater Bay/Moisture Separator Area
Travel Path
05/13/2025
71151
Calculations
OpenEMS Effluent Permits
Various
71151
Calculations
CY-AA-130-3010-
F-03
Dose Equivalent Iodine Determination
Various
71151
Miscellaneous
LER 237/2024-001-
Containment Cooling Service Water Valve Failure Resulted in
a Condition Prohibited by Technical Specifications and Loss
of Safety Function
01/27/2025
71151
Miscellaneous
LER 249/2024-002-
Low Pressure Coolant Injection Pump Suction Relief Valve
Inoperable as a Primary Containment Isolation Valve
Resulted in a Condition Prohibited by Technical
01/21/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Specifications
71151
Miscellaneous
Monthly Data Elements for NRC ROP Indicator - Reactor
Coolant System (RCS) Specific Activity
Various
71151
Miscellaneous
Monthly Data Elements for NRC ROP Indicator -
Occupational Exposure Control Effectiveness
Various
71151
Miscellaneous
Monthly Data Elements for NRC ROP Indicator -
RETS/ODCM Radiological Effluent Occurrences
Various
Corrective Action
Documents
DBG Descended Away from Grapple during Transfer in U3
10/08/2025
Corrective Action
Documents
Discovered Water Leak in L.P. Heater Bay
11/05/2025
Drawings
M-22
Diagram of Service Water Piping
Procedures
DFP 0800-08
Blade Guide Inspection, Storage, and Movement
27