IR 05000237/2024001

Integrated Inspection Report 05000237/2024001 & 05000249/2024001

ML24121A249
Person / Time
Site:	Dresden
Issue date:	05/01/2024
From:	Robert Ruiz NRC/RGN-III/DORS/RPB1
To:	Rhoades D Constellation Energy Generation
References
IR 2024001
Download: ML24121A249 (1)

Text

SUBJECT:

DRESDEN NUCLEAR POWER STATION, UNITS 2 AND 3 - INTEGRATED INSPECTION REPORT 05000237/2024001 AND 05000249/2024001

Dear David Rhoades:

On March 31, 2024, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Dresden Nuclear Power station, Units 2 and 3. On April 16, 2024, the NRC inspectors discussed the results of this inspection with C. Joseph, Site 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, 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

Inspection Report

Docket Numbers: 05000237 and 05000249

License Numbers: DPR-19 and DPR-25

Report Numbers: 05000237/2024001 and 05000249/2024001

Licensee: Constellation Energy Generation, LLC

Facility: Dresden Nuclear Power station, Units 2 and 3

Location: Morris, IL

Inspection Dates: January 01, 2024 to March 31, 2024

Inspectors: A. Anderson, Physical Security Inspector J. Kutlesa, Sr. Emergency Preparedness Inspector K. Maloney, Sr. Physical Security Inspector J. Meszaros, Resident Inspector M. Porfirio, Illinois Emergency Management Agency C. St. Peters, Resident Inspector J. Steffes, Senior Resident Inspector

Approved By: Robert Ruiz, Chief Reactor Projects Branch 1 Division of Operating Reactor Safety

Enclosure

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

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 1, 2024, power was reduced to approximately 57 percent to perform rod sequence exchange and scram valve maintenance. The unit returned to rated thermal power the next day 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 March 8, 2024, power was reduced to approximately 66 percent to perform rod sequence exchange and scram valve maintenance. The unit returned to rated thermal power the next day. On March 14, 2024, the licensee noted a rise in drywell pressure and dual indication of the 1A main steam isolation valve (MSIV). Unit power was reduced to approximately 25 percent to facilitate drywell entry for troubleshooting a repair. Following repairs to the 1A MSIV pneumatic line the unit was returned to rated thermal power on March 16, 2024. On March 17, 2024, unit power was reduced to approximately 81 percent for scram valve maintenance. The unit returned to rated thermal power the same day 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.

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:

Emergency diesel generators (EDGs), ultimate heat sink and associated cooling water systems, station blackout (SBO) diesel generators from January 17 - 19, 2024.

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 3 EDG on January 17 - 18, 2024

(2) Unit 3 isolation condenser during high pressure coolant injection work window on February 26 - 27, 2024

(3) Unit 2 EDG while the 2/3 EDG was inoperable for maintenance on March 25 - 26, 2024

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) 1.1.1.5A Unit 3 isolation condenser area elev. 589' and FZ 1.1.2.5A Unit 2 isolation condenser area elev. 589' on January 4, 2024

(2) FZ 11.2.1 Unit 2 southwest corner room elev. 476' on January 5, 2024

(3) FZ 6.2 Unit 2/3 comp room & auxiliary electrical room elev. 517' on January 11, 2024

Fire Brigade Drill Performance Sample (IP Section 03.02) (1 Sample)

(1) The inspectors evaluated the onsite fire brigade training and performance during an unannounced fire drill on March 14, 2024.

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 planned down power for rod sequence exchange, rod recovery, and control rod drive testing on March 1 - 2, 2024.

Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)

(1) The inspectors observed and evaluated an out of the box scenario, CPE OBE A, in the main control room simulator on March 19, 2024.

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) Unit 3 125 volts direct current (VDC) batteries following identification of lid cracking and bulging on the Unit 3 125 VDC batteries

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management Sample (IP Section 03.01) (2 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 3 plant risk action green and fire risk blue due to planned work window on high pressure coolant injection, on February 26-27, 2024

(2) Unit 3 emergent down power and 1A MSIV manifold o-ring replacement, on March 14-15, 2024

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) Main control room heating, ventilation and air conditioning damper not positioning properly during DFPS 4183-14, as documented in CR 4723462

(2) Unit 3 125 VDC battery cell 23 has crack on lid and lid is lightly bulging out near post, as documented in CR 4730791

(3) Unit 2 SBO engine "B" oil cooler in low as documented in CR 4730965

(4) Unit 3 "A" reactor building closed cooling water temperature control valve will not open past 65percent, as documented in CR 4749275

(5) Unit 2 125 VDC battery charger 2A fluctuating direct current output, as documented in CR 4752128

(6) Unit 3 SBO jacket water expansion tank level low, as documented in CRs 4741960 and 4741962

71111.18 - Plant Modifications

Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02)

(1 Partial)

The inspectors evaluated the following temporary or permanent modifications:

(1) (Partial)

The NRC staff completed a review of the licensee's hazard assessment associated with a hypothetical rupture and subsequent release of natural gas of the planned Three Rivers Lateral pipeline lateral to the Dresden Power Station Unit 2 and 3. The results of this review are documented in ADAMS under ML24071A123 and did not identify any safety or regulatory concerns. To complete the sample the inspectors will conduct onsite verification of installation and testing requirements once the pipeline construction is completed to ensure hazard analysis assumptions.

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) (3 Samples)

(1) Unit 3 SBO diesel following 2-year preventative maintenance, per Work Order (WO)

===5278040-02

(2) Unit 2 control rod drives H-12, K-4, N-9, K-14, and H-9 testing following diaphragm replacement, per WO 5481697

(3) Unit 3 drywell pneumatic air flow qualitative air leakage assessment following emergent work on the 1A MSIV air manifold, per WO 5518072

Surveillance Testing (IP Section 03.01)===

(1) DOS 6600-01, 2/3 Emergency Diesel Generator monthly surveillance test, on March 27, 2024

Inservice Testing (IST) (IP Section 03.01) (1 Sample)

(1) Unit 3 DOS 2300-03, High Pressure Coolant Injection System Operability and Quarterly IST Verification Test, per WO 5425673

71114.02 - Alert and Notification System Testing

Inspection Review (IP Section 02.01-02.04) (1 Sample)

(1) The inspectors evaluated the following maintenance and testing of the alert and notification system:

• Annual siren inspection and maintenance records for the period of March 2022 to March 2024.

• Weekly alert notification system (siren) tests for the period of March 2022 to March 2024.

71114.03 - Emergency Response Organization Staffing and Augmentation System

Inspection Review (IP Section 02.01-02.02) (1 Sample)

(1) The inspectors evaluated the readiness of the Emergency Preparedness Organization.

71114.05 - Maintenance of Emergency Preparedness

Inspection Review (IP Section 02.01 - 02.11) (1 Sample)

(1) The inspectors evaluated the maintenance of the emergency preparedness program.

OTHER ACTIVITIES - BASELINE

===71151 - Performance Indicator Verification

The inspectors verified licensee performance indicators submittals listed below:

IE01: Unplanned Scrams per 7000 Critical Hours Sample (IP Section 02.01)===

(1) Unit 2 (January 1, 2023 through December 31, 2023)

(2) Unit 3 (January 1, 2023 through December 31, 2023)

IE03: Unplanned Power Changes per 7000 Critical Hours Sample (IP Section 02.02) (2 Samples)

(1) Unit 2 (January 1, 2023 through December 31, 2023)

(2) Unit 3 (January 1, 2023 through December 31, 2023)

IE04: Unplanned Scrams with Complications (USwC) Sample (IP Section 02.03) (2 Samples)

(1) Unit 2 (January 1, 2023 through December 31, 2023)

(2) Unit 3 (January 1, 2023 through December 31, 2023)

EP01: Drill/Exercise Performance (DEP) Sample (IP Section 02.12) (1 Sample)

(1) January 01, 2022 through December 31, 2023.

EP02: Emergency Response Organization (ERO) Drill Participation (IP Section 02.13) (1 Sample)

(1) January 01, 2022 through December 31, 2023.

EP03: Alert and Notification System (ANS) Reliability Sample (IP Section 02.14) (1 Sample)

(1) January 01, 2022 through December 31,

INSPECTION RESULTS

No findings were identified.

EXIT MEETINGS AND DEBRIEFS

The inspectors verified no proprietary information was retained or documented in this report.

• On April 16, 2024, the inspectors presented the integrated inspection results to C. Joseph, Site Vice President, and other members of the licensee staff.

• On March 29, 2024, the inspectors presented the Emergency Preparedness inspection results to H. Patel and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection Type Designation Description or Title Revision or

Procedure Date

71111.01 Procedures DOS 0010-19 Preparation for Cold Weather Operations for Unit 1 and Out 49

Buildings

DOS 0010-22 Preparation for Cold Weather Operations for Unit 2 27

DOS 0010-25 Preparation for Cold Weather Operations for Unit 3 24

OP-DR-108-111-Cold Weather Strategy 1

1004

71111.04 Corrective Action 4760987 NRC Question: U2 EDG Room Walkdown 03/25/2024

Documents

Resulting from

Inspection

Drawings M-173 Diagram of Corrosion Test and Diesel Start-up Air Piping BJ

M-22 Diagram of Service Water Piping FA

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 Coolant Water System J

M-517 Diesel Generator Engine Cooling Water System I

M-518 Diesel Generator Fuel Oil System F

M-518 Diesel Generator Fuel Oil System G

Procedures DOP 1300-M1/E1 Unit 3 Isolation Condenser System Checklist 26

DOP 6600-01 Diesel Generator 2(3) Preparation for Standby Operation 34

DOP 6600-M1 Unit 2 Standby Diesel Generator 30

DOS 6600-M1 Unit 3 Standby Diesel Generator Checklist 29

71111.05 Fire Plans 100 Pre-fire Plan Dresden Generating Station Pre-Fire Plan 3

Master Legend

2 U2RB-2 FZ 11.2.1 Unit 2 Southwest Corner Room Elev. 476' 4

115 U2RB-12 FZ 1.1.2.5A Unit 2 Isolation Condenser Area Elev. 589' 2

131 U3RB-31 FZ 1.1.1.5A Unit 3 Isolation Condenser Area Elev. 589' 3

143 U2TB-46 FZ 6.2 Unit 2/3 Comp Room & Auxiliary Electrical Room 4

Elev. 517'

173 U3TB-84 FZ 8.2.8A Unit 3 Main Turbine Floor Eleve. 561' 5

Miscellaneous DR-CM-35 Development of Risk Management Actions for the Inclusion 0

Inspection Type Designation Description or Title Revision or

Procedure Date

of Fire Insights into Dresden Nuclear Power Station

Configuration Risk Management Program

Fire Drill Scenario Turbine Services Office Fire U3 TB 561' 03/14/2024

24-02

Procedures ER-DR-600-1069 Dresden Units 2 & 3 Site List of High Risk Fire Areas 0

OP-AA-201-107 Fire Protection Impairment Control 2

71111.11Q Miscellaneous Dresden Unit 2 - D2 1st Quarter 2024 Load Drop Profile 03/1/2024

Procedures NF-AB-720-F-5 Special Maneuver Rod Move Sheet 3

OP-AA-101-113-Attachment 2, Operator Fundamentals Coding Matrix 12

1006

OP-AB-300-1003 ReMA First Quarter 2024 Load Drop 20

71111.12 Corrective Action 4683379 U3 125VDC Alternate Battery Cell 12 Crack on Positive Post06/08/2023

Documents 4692463 U3 125VDC Main Battery Cracks 07/25/2023

4692472 U3 125VDC Alternate Battery Cracks 07/25/2023

4696927 U3 125 VDC Alt Battery Cell #2 Detectable Leak 08/16/2023

4702635 Surface Crack on Battery Cell Lid 09/14/2023

27513 Leak on U3 125VDC Alt Battery Cell Number 2 01/08/2024

Miscellaneous System Health AC/DC Distribution System Health Report 01/12/2024

Report

Procedures DOS 8300-01 Unit 2(3) Weekly Station Battery Inspection 17

DOS 8300-17 Unit 2(3) Quarterly Station Battery Inspection 23

Work Orders 5412586 OP D3 Qtr TS Alt 125V DC Station Battery Surveillance 12/7/2023

(In Lieu of wkly/mnt)

5412598 OP D3 IM PM TSNC 125 VDC Station Battery Inspection 11/23/2023

71111.13 Corrective Action 4758041 Unit 3 DW Pressure Response 03/14/2024

Documents 4759564 MSIV 3-0203-1A pneumatic leak (Failed Airline and O-Ring) 03/14/2024

Procedures OP-AA-101-113-Prompt Investigation 49

1004

OP-AA-108-117 Protected Equipment List 02/26/2024

OP-DR-201-012-Dresden On-Line Fire Risk Management 8

1001

WC-AA-101-1006 On-Line Risk Management and Assessment 4

71111.15 Corrective Action 4395594 U2 125VDC Battery Charger 2A Fluctuating DC Output 01/13/2021

Inspection Type Designation Description or Title Revision or

Procedure Date

Documents Current

4396948 U2 125VDC Battery Charger 2A Fluctuating DC Output 01/20/2021

Current

4533410 3A RBCCW TCV Appears Stuck 10/30/2022

4540705 3A RBCCW TCV will Not Open Past 65% 12/04/2022

23462 MCR HVAC Not Positioning Properly during DFPS 4183-14 12/14/2023

4730791 Unit 3 125 VDC Battery Cell 23 Has Crack on Lid and Lid is 01/4/2024

Lightly Bulging out Near +Post

4749275 3A RBCCW TCV will Not Open Past 65% 02/11/2024

4752128 U2 125VDC Battery Charger 2A Fluctuating DC Output 02/21/2024

Current

Miscellaneous DAN 223-89 B-3 Cont Rm/East Turb Bldg Ductwork Smoke Detected 5

Procedures DFPS 4183-14 Unit 2/3 Control Room HVAC Smoke Detector Annual 19

Surveillance Procedure

DOP 3700-02 Reactor Building Closed Cooling Water System Operation 44

Work Orders 5105466 125VDC Station Battery Inspection 01/13/2021

5115597 U2 125VDC Battery Charger 2A Fluctuating DC Output 01/14/2021

Current

71111.24 Corrective Action 4493791 U3 SBO Engine A Lube Oil Sump Level Lo Alarm 04/18/2022

Documents

Procedures DMP 0200-05 Main Steam Isolation Valve Operator Air Manifold 3

Replacement and Air Operator Testing

DOS 0300-14 Control Rod Drive Scram Testing At Power 47

DOS 4700-02 Drywell Pneumatic Air Flow Qualitative Air Leakage 11

Assessment

DOS 6600-01 Diesel Generator Surveillance Tests 148

MA-AA-716-012 Post Maintenance Testing 27

Work Orders 1901879 Op Open/Close Breakers 3-6771-4, Bus 34 Feed ESS Div II 01/10/2024

+ PMT

1905271 EM Swap SBO Diesel Generator 3 Feed 3-6771-1 01/8/2024

5052618 Op PMT 3B SBO Start Air Part Filter 3-4680-7B for Leaks 01/12/2024

269522 OP D3 2Y PM HPCI Fast Initiation Test 02/29/2024

278040 D3 2Y PM SBO Mechanical Maintenance Inspection 02/03/2024

Inspection Type Designation Description or Title Revision or

Procedure Date

29595 Diesel Fuel Oil Leak on Fitting Return Line for U3 SBO 02/03/2024

5385644 U3 SBO Engine A Lube Oil Sump Level Lo Alarm 02/03/2024

5407889 D3 Qtr Com SBO Diesel Generator Surveillance 02/03/2024

25673 OP D3 Quarterly TS HPCI Pump Operability Test and IST 02/29/2024

Surveillance

5481697 Need a WO to replace U2 SSPV Diaphragms 03/01/2024

5518072-5 MM Install New O-Rings AVCO Mnfld ASM (OPCC) 03/15/2024

5518072-7 Ops PMT 1A MSIV After O-Ring Replacement 3/16/2024

71114.02 Miscellaneous N/A Dresden Monthly Siren Availability Report (Telemetry) January

22 through

December

23

N/A Exelon Mid-West Siren Status Report January

22 through

December

23

71114.03 Calculations EP-AA-1004 Dresden Station On-Shift Staffing Technical Basis Rev 02

Addendum 1

Miscellaneous N/A Quarterly Call-In Augmentation Drill Results 1st Qtr 2022

- 4th Qtr

23

Procedures EP-AA-1004 Exelon Nuclear Radiological Emergency Plan Annex for Rev 39

Dresden Station

EP-DR-1000 Dresden Station Radiological Emergency Plan Rev 0

71114.05 Calculations KLD TR - 1252 DRESDEN GENERATING STATION Development of 07/25/2022

Evacuation Time Estimates

Miscellaneous Letters of Coal City Fire Protection District; GE Morris Facility; Grundy Various

Agreement County Sherriff; Morris Hospital; Presence St. Joseph

Medical Center; US Army Corp of Engineers

Procedures EP-DR-124-F-Inventories: TSC, OSC, Control Room January

01/02/03 2022 through

December

23

Self-Assessments NOSA-DRE-22-Emergency Preparedness Audit 04/25/2022

Inspection Type Designation Description or Title Revision or

Procedure Date

(AR 4478144)

71151 Miscellaneous NRC Performance Indicator Data: Initiating Events - 01/01/2023-

Unplanned Power Changes per 7000 Critical Hours 12/31/2023

NRC Performance Indicator Data: Initiating Events - 01/01/2023-

Unit/Reactor Shutdown Occurrences 12/31/2023

LS-AA-2110 Monthly Data Elements for NRC ROP Indicator - Emergency 1st Qtr 2022

Response Organization (ERO) Drill Participation - 4th Qtr

23

LS-AA-2120 Monthly Data Elements for NRC ROP Indicator - 1st Qtr 2022

Drill/Exercise Performance - 4th Qtr

23

LS-AA-2130 Monthly Data Elements for NRC ROP Indicator - Alert and 1st Qtr 2022

Notification System Reliability - 4th Qtr

23

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