IR 05000461/2024001

Integrated Inspection Report 05000461/2024001

ML24127A091
Person / Time
Site:	Clinton
Issue date:	05/07/2024
From:	Robert Ruiz NRC/RGN-III/DORS/RPB1
To:	Rhoades D Constellation Energy Generation, Constellation Nuclear
References
IR 2024001
Download: ML24127A091 (1)

Text

SUBJECT:

CLINTON POWER STATION - INTEGRATED INSPECTION REPORT 05000461/2024001

Dear David P. Rhoades:

On March 31, 2024, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Clinton Power Station. On April 17, 2024, the NRC inspectors discussed the results of this inspection with Norha Plumey, 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 No. 05000461 License No. NPF-62

Enclosure:

As stated

Inspection Report

Docket Number: 05000461

License Number: NPF-62

Report Number: 05000461/2024001

Licensee: Constellation Nuclear

Facility: Clinton Power Station

Location: Clinton, IL

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

Inspectors: J. Benjamin, Senior Resident Inspector A. Muneeruddin, Resident Inspector J. Murphy, Illinois Emergency Management Agency J. Steward, 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 Clinton Power 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.

PLANT STATUS

Unit 1 began the inspection period at rated thermal power (RTP). On March 9, 2024, Unit 1 lowered reactor power to 75 percent RTP to perform a planned control rod sequence exchange and main steam isolation valve (MSIV) surveillance testing. On March 10, 2024, the unit returned to RTP. On March 24, 2024, Unit 1 lowered reactor power to 75 percent RTP to perform planned MSIV surveillance testing and perform data gathering to confirm results of testing of inboard MSIV 1B21-F022D close limit switch, which failed surveillance testing on March 9, 2024. Inboard MSIV 1B21-F022D valve operated satisfactorily, however the limit switch failed to provide an input to the reactor protection system upon valve closure. Following completion of activities requiring reduced reactor power, the unit was returned to RTP on March 24, 2024, and continued to operate at or near RTP 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: diesel fire pumps

'A' and 'B', FLEX system equipment, and divisions 1, 2, and 3 of shutdown service water on January 31, 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) diesel fire pumps 'A' and 'B' on January 31, 2024

(2) fire protection jockey pump skid in the makeup water pump house on February 7, 2024

(3) high-pressure core spray during low-pressure core spray system outage window on March 14, 2024

71111.05 - Fire Protection

Fire Area Walkdown and Inspection Sample (IP Section 03.01) (5 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 Areas CB-5a and CB 5-b, control building, elevation 781', division 3 switchgear and battery room on January 17, 2024

(2) Fire Areas M-1, M-2(a) and M-2(b), elevation 699', screen house divisions 1, 2 and 3 service water (SX) pump rooms and tunnel on January 30, 2024

(3) Fire Area M-4, elevation 699', screen house 'A' (north) fire pump room on January 30, 2024

(4) Fire Area M-3, elevation 699', screen house 'B' (south) fire pump room on January 31, 2024

(5) Fire Area D-10, diesel generator building, elevation 762', diesel generator (DG)heating ventilation and air conditioning (HVAC) equipment area and Unit 2 rooms on March 29, 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 announced fire drill on March 29, 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 a planned downpower to 75 percent RTP for MSIV surveillance testing on March 24, 2024.

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

(1) The inspectors observed and evaluated licensed operator requalification simulator training on February 2, 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) division 3 switchgear heat removal loss of 120-volt alternating current control power due to loose connection on fuse block for condensing unit 1vx06cc per Work Order (WO) 5481695 on February 21, 2024

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) elevated online risk due to residual heat removal pump 'B' minimum flow valve, 1E12-F064B, planned system outage window on February 27, 2024

(2) elevated online risk due to planned system outage window work on the 'B' reserve auxiliary transformer from March 19, 2024 to March 21, 2024

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment (IP Section 03.01) (4 Samples)

The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:

(1) division 3 switchgear and battery room temperature low on January 17, 2024

(2) division 1 and division 2 diesel generator 12-cylinder and 16-cylinder fuel priming pump lube oil leakage catch containment installation per Action Request (AR) 4747072 on February 7, 2024

(3) division 3 switchgear heat removal loss of control power per AR 4748580 on February 12, 2024

(4) inboard main steam isolation valve (MSIV) 1B21-F022D failure to trip reactor protection system during surveillance testing per AR 4756831 on March 14, 2024

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)

(1) main feeder breaker 1A1, trip hand switch repair per AR 4707150 on January 9, 2024

(2) reactor recirculation hydraulic power unit subloop A-2 PMT following filter element replacement and lubrication of pump and motor coupling on February 12, 2024

(3) residual heat removal pump 'B' minimum flow valve 1E12-F064B valve stroke and position verification following motor-operated valve thrust verification clean and inspect per WO 5251529-04 on February 28, 2024

(4) diesel fire pump 'A' (1FP01PA) pressure transducer replacement per WO 5460717 on March 12, 2024

(5) containment to secondary containment positioner actuator, 1VR004Y, PMT following repair and adjustment per WO 05414021-09 on March 14, 2024

(6) control room chiller 'A' time delay relay replacement and PMT per WOs 5518353 and

===5518353-03 on March 20, 2024

(7) PMT of reserve auxiliary transformer 'B' load tap changer repairs per WOs 5414582-63, 5414583-64 and 5414582-69 on March 21, 2024

Surveillance Testing (IP Section 03.01)===

(1) exercise test of 1SX016B per WO 5273960 on February 13, 2024

(2) standby gas train 'A' flow/heater operability per WO 5419353 on February 29, 2024

(3) flex hale pump 'A' (1FX01PA) annual performance test per WO 5392379 on March 11, 2024

Inservice Testing (IST) (IP Section 03.01) (3 Samples)

(1) division 3 fuel oil transfer pump operability in service test per WO 5415185 on February 16, 2024

(2) reactor core isolation cooling (1E51-C001) high-pressure operability checks per WO 5421382 on February 22, 2024

(3) low-pressure core spray valve operability checks per CPS 9052.02 on March 19, 2024

Diverse and Flexible Coping Strategies (FLEX) Testing (IP Section 03.02) (1 Sample)

(1) annual operational performance test of FLEX diesel generator 2, 1FX01KB, per WO 5323379 on February 21,

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

IE03: Unplanned Power Changes per 7000 Critical Hours Sample (IP Section 02.02) (1 Sample)

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

IE04: Unplanned Scrams with Complications (USwC) Sample (IP Section 02.03) (1 Sample)

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

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 17, 2024, the inspectors presented the integrated inspection results to Norha Plumey, Site Vice President, and other members of the licensee staff.

THIRD PARTY REVIEWS

Inspectors reviewed the most recent WANO report for the Clinton site that was issued in August 2023.

DOCUMENTS REVIEWED

Inspection Type Designation Description or Title Revision or

Procedure Date

71111.04 Drawings M05-1039, Sheet Fire Protection (Screen House) AX

M05-1039, Sheet Fire Protection Outdoor AT

M05-1039, Sheet Fire Protection Pump House AE

M05-1074 P&ID High Pressure Core Spray (HP) AH

Procedures CPS Fire Detection and Protection Valve Lineup 22d

213.01V001

CPS High Pressure Core Spray Electrical Lineup 8b

3309.01E001

CPS High Pressure Core Spray Valve Lineup 11b

3309.01V001

71111.05 Fire Plans CPS 781 Control Building Div 3 Switchgear and Battery Room 6b

1893.04M353

CPS 762 Diesel Generator: Diesel Generator HVAC Equipment 5c

1893.04M523 Area and Unit 2 Rooms Pre-Fire Plan

CPS 699 Screen House: Div 1 SX Pump Room Pre-Fire Plan 5a

1893.04M800

CPS 699 Screen House: Div 2 and 3 SX Pump Rooms and Tunnel 6a

1893.04M801 Pre-Fire Plan

CPS 699 Screen House: 'B' (South) Fire Pump Room Pre-Fire Plan6a

1893.04M802

CPS 699 Screen House: 'A' (North) Fire Pump Room Pre-Fire Plan6b

1893.04M803

Miscellaneous 2024-05 Fire Drill Record 03/29/2024

71111.11Q Miscellaneous ESG LOR-OBE- Clinton Power Station Licensed Operator Training Simulator 000

001 Exercise Guide

Procedures CPS 3005.01 Unit Power Changes 53

CPS 3105.05 Generator (TG) 23e

CPS 3302.01 Reactor Recirculation (RR) 39e

71111.13 Miscellaneous Clinton Clean Energy Center Plan of the Day for February 26, 02/26/2024

24

Clinton Clean Energy Center Plan of the Day for March 19-21, 03/21/2024

24

71111.15 Calculations IP-M-0145 Evaluation of VX 30 Minute Time Delay Based on 02/15/2024

Temperature Rise Data

IP-M-0750 Evaluation of Division 3 Battery Room Temperature Upon 02/15/2024

Loss of Cooling

Corrective Action AR 4731207 Div 3 Switchgear and Battery Room Temperature Low 01/16/2024

Documents

Engineering ECR 461451 01/19/2024

Evaluations ECR 461739 Division III VX Past Operability Concern 02/09/2024

Miscellaneous 1501, 1502 Transient Combustible Permits 02/07/2024

ESOMS ESOMS Operations Narrative Log 01/17/2024

Operability CL1-22A-001 Paragon RICT Package for 1B21-F022D 03/14/2024

Evaluations

Procedures 9382.01 125VDC Battery Pilot Cell Check 40

ER-CL-600-2001 Clinton RICT System Guidelines 0

OP-AA-108-118 Risk Informed Completion Time 3

71111.24 Miscellaneous 192858-21 PMRQ 03/11/2024

Procedures 9000.01D001 Control Room Surveillance Log - Mode 1,2,3 Data Sheet 59b

9061.06C013 Div 2 Fuel Pool Makeup Isol Valve Operability (SX in Service) 37b

Checklist

9061.06D013 Div 2 Fuel Pool Makeup Isol Valve Operability (SX in Service) 36

Data Sheet

9080.12 Fuel Oil Transfer Pump Operability 38

CPS 3862.01 Flex Diesel Generator Operation 2

CPS 9052.02 Low-Pressure Core Spray Valve Operability Checks 33d

CPS LPCS Valve Operability Data Sheet 31f

9052.02D001

CPS 9067.01 Standby Gas Treatment System Train Flow/Heater Operability 32c

CPS 9071.02 Diesel Fire Pump Capacity Checks 45d

Work Orders Various Work WOs 5351118, 5295740, 5467196

Orders for LPCS

Maintenance and

Testing

WO 5199261 EM 9381.01LP1 MOV Therm Ovrld Byp Verif 1E21F001,11,12 03/19/2024

WO 5350821 9071.02R20 OP Fire Pump A Capacity/Controls Test 03/12/2024

WO 5414582-57 Verify RAT 'B' Load Tap Changer in Manual 03/21/2024

WOs 52440299 Work Orders for 1SX016B Valve Exercise Testing 02/13/2024

and 5273960

WOs 5383684, Various Reactor Recirculation A-2 Subloop Work Orders 02/12/2024

5384182 and

5415178

WOs 5518353 Replace VC Chiller A Program Timer Relay, 0KYVC019 03/20/2024

and 5518353-03

71151 Corrective Action AR 4680584 Drywell Floor Drain in Leakage High After Startup from C1M2610/13/2023

Documents

Miscellaneous AC-RF-2306- Adverse Condition Monitoring and Contingency Plan - 05/25/2023

0001 Elevated Drywell Floor Drain Leakage

LS-AA-2001 Collection and Reporting of NRC ROP Performance Indicator 17

Data

Procedures NEI 99-02 Regulatory Assessment Performance Indicator Guideline 7

10