IR 05000373/2025010
| ML25177B708 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 06/27/2025 |
| From: | Jasmine Gilliam NRC/RGN-III/DORS/EB2 |
| To: | Rhoades D Constellation Energy Generation |
| References | |
| IR 2025010 | |
| Download: ML25177B708 (1) | |
Text
SUBJECT:
LASALLE COUNTY STATION - AGE-RELATED DEGRADATION INSPECTION REPORT 05000373/2025010 AND 05000374/2025010
Dear David Rhoades:
On May 22, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at LaSalle County Station and discussed the results of this inspection with Joseph Reda, Plant Manager, 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 LaSalle County Station.
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 LaSalle County Station.
June 27, 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, Jasmine A. Gilliam, Chief Engineering Branch 2 Division of Operating Reactor Safety Docket Nos. 05000373 and 05000374 License Nos. NPF-11 and NPF-18
Enclosure:
As stated
Inspection Report
Docket Numbers:
05000373 and 05000374
License Numbers:
Report Numbers:
05000373/2025010 and 05000374/2025010
Enterprise Identifier:
I-2025-010-0051
Licensee:
Constellation Nuclear
Facility:
LaSalle County Station
Location:
Marseilles, IL
Inspection Dates:
April 28, 2025 to May 22, 2025
Inspectors:
T. Briley, Senior Reactor Inspector
A. Dahbur, Senior Reactor Inspector
A. Hobbs, Reactor Inspector
Approved By:
Jasmine A. Gilliam, Chief
Engineering Branch 2
Division of Operating Reactor Safety
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an Age-Related Degradation Inspection at LaSalle County 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
Failure to Refurbish or Replace Safety-Related General Electric Switch Block Miniature Hand-Switch in Accordance with Performance Centered Maintenance Template Cornerstone Significance Cross-Cutting Aspect Report Section Initiating Events Green NCV 05000373/2025010-01 Open/Closed
[P.3] - Resolution 71111.21N.04 The inspectors identified a Green finding and associated non-cited violation (NCV) of Technical Specification 5.4.1, Procedures, when the licensee failed to refurbish or replace the General Electric switch block miniature (SBM) hand switch 1HS-AP044, switchgear 141Y feed from station auxiliary transformer (ACB1412), in accordance with the time directed intervals specified by the performance centered maintenance (PCM) template for manual switches.
Additional Tracking Items
None.
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 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
71111.21N.04 - Age-Related Degradation Age-Related Degradation
The inspectors evaluated that engineering performance and maintenance activities to address age-related degradation for the following plant structures and components were being conducted in a manner that provided reasonable assurance of the safe operation of the plant. The inspectors also evaluated that age-related degradation for the following plant structures and components were appropriately identified, addressed, and corrected.
- (1) Unit 1 and Unit 2, Division 3, 125 Volt Batteries
- (2) Unit 1 and Unit 2, Division 3, 125 Volt Battery Chargers
- (3) Control Room Heating Ventilation Air Conditioning System Fan Motors
- (4) Unit 1 Primary Containment Vacuum Breakers
- (5) Unit 1 and Unit 2, Core Standby Cooling System (CSCS) piping
- (6) Unit 1 and unit 2, Recirculation Flow Control Valves
- (7) Unit 2 Residual Heat Removal Service Water Pump B
- (8) General Electric Type Switch Block Miniature (SBM) Switches
- (9) Unit 1 and Unit 2, Division 1 and Division 2, Emergency Diesel Generator Fuel Storage Tanks
- (10) Unit 2, Division 1 and Division 2, Diesel Generator Coolers
INSPECTION RESULTS
Failure to Refurbish or Replace Safety-Related General Electric Switch Block Miniature Hand-Switch in Accordance with Performance Centered Maintenance Template Cornerstone Significance Cross-Cutting Aspect Report Section Initiating Events Green NCV 05000373/2025010-01 Open/Closed
[P.3] - Resolution 71111.21N.04 The inspectors identified a Green finding and associated non-cited violation (NCV) of Technical Specification 5.4.1, Procedures, when the licensee failed to refurbish or replace the General Electric switch block miniature (SBM) hand switch 1HS-AP044, switchgear 141Y feed from station auxiliary transformer (ACB1412), in accordance with the time directed intervals specified by the performance centered maintenance (PCM) template for manual switches.
Description:
On February 17, 2019, a General Electric switch block miniature (SBM) hand switch (2E12-S803A) associated with the unit 2, 2D residual heat removal service water pump failed.
This SBM switch failure resulted in the pump being unable to readily start when the hand switch to start the component was manipulated in preparation for a planned unit 2 refueling outage. The licensee performed a casual evaluation (Issue Report (IR) 04220852) and determined that the SBM switch failure was a result of high contact resistance due to surface contamination from the manufacturing process (SBM switch was installed in 2012). The failed SBM switch was subsequently replaced. As part of the causal evaluation, the licensee generated numerous corrective actions, which included an action tracking item for engineers to review SBM switches for appropriate component classification and maintenance strategy.
Component classification included determining component criticality, duty cycle, operating environment, and vulnerabilities.
An engineering system review completed on approximately July 30, 2019, as part of action tracking item 04220852-04, identified twenty-eight SBM switches classified as critical components that did not have a refurbishment or replacement preventative maintenance strategy in place as expected. For those critical SBM switches, the performance centered maintenance (PCM) template had recommended a 20-year refurbishment or replacement time interval be established. The PCM templates identified the specific tasks (condition monitoring, condition directed, time directed, or surveillances) and frequencies recommended for components to minimize consequential failures based on the criticality of the component, how often it's used, and the environment in which it operates. A preventative maintenance modification request (PMMR) PMC-19-120164 was subsequently created on approximately August 2, 2019, to establish the 20-year refurbishment or replacement maintenance strategy for those twenty-eight SBM switches.
The inspectors requested information on SBM switches on March 20, 2025, as part of preparation for this inspection, and it was identified on April 21, 2025 (IR 04860048) that the twenty-eight critical SBM switches described above did not have refurbishment or replacement preventative maintenance activities established. The PMMR developed in 2019 remained in draft status for over four years and was subsequently cancelled (unknown reason) on approximately October 25, 2023. The licensee determined that twenty-seven of the twenty-eight SBM switches without a 20-year preventative maintenance activity in place for refurbishment or replacement had actually been previously replaced under a different, one-time SBM switch replacement initiative, which was within the desired 20-year time interval. However, for one SBM switch - 1HS-AP044, switchgear 141Y feed from station auxiliary transformer (ACB1412) - classified as critical, low duty cycle, and mild environment (classification code D/4) - the licensee was unable to identify any records indicating refurbishment or replacement, nor technical basis for PCM template deviation, and the installed SBM switch was believed to be over 40 years old. Switchgear 141Y was a unit 1, division 1, 4160 volt safety-related bus for which a station auxiliary transformer provided the normal source of off-site power to the various 141Y electrical loads.
Licensee procedure ER-AA-200, Preventative Maintenance Program, Revision 7, establishes requirements for preventative maintenance program development and implementation.
ER-AA-200, step 1.1 states, in part, the purpose of the preventative maintenance program, using the PCM maintenance strategy analysis tools and other processes, is to maintain plant structures, systems, and components at an appropriate state of reliability. Step 4.3.5 states, in part, the PCM template is to be used as the starting point for the development of the maintenance strategy. Step 4.3.6 states, in part, all PCM template deviations have a technical basis documented by the site subject matter expert.
Corrective Actions: A work order request was generated to replace SBM switch 1HS-AP044, switchgear 141Y feed from station auxiliary transformer (ACB1412), during the next planned refueling outage. In addition, an evaluation was performed to justify continued SBM switch operation until replacement. A new PMMR (PMC-25-156724) was generated to initiate preventative maintenance activities in accordance with the PCM template for the twenty-eight SBM switches that did not already have in place.
Corrective Action References: 04860048
Performance Assessment:
Performance Deficiency: The licensees failure to refurbish or replace the General Electric switch block miniature (SBM) hand switch 1HS-AP044, switchgear 141Y feed from station auxiliary transformer (ACB1412), in accordance with the time directed intervals specified by the performance centered maintenance (PCM) template for manual switches was a performance deficiency.
Screening: The inspectors determined the performance deficiency was more than minor because if left uncorrected, it would have the potential to lead to a more significant safety concern. Specifically, the PCM template recommended refurbishment or replacement interval was determined to be 20 years. The licensee was unable to identify any information to show that the switch had ever been replaced and was assumed to be over 40 years old, more than double the recommended replacement frequency. With the cancellation of the preventative maintenance request created in 2019 to perform the 20-year refurbish or replace frequency, there was the potential the switch may not have been replaced for the future life of the plant, which could challenge its continued reliability.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The finding was determined to be of very low safety significance (Green) because the inspectors answered no to all the questions in Exhibit 1, Initiating Events Screening Questions.
Cross-Cutting Aspect: P.3 - Resolution: The organization takes effective corrective actions to address issues in a timely manner commensurate with their safety significance. Specifically, although an issue report was generated in 2019 that prompted the creation of a preventative maintenance modification request to perform the 20-year refurbishment or replacement preventative maintenance activities, the request remained in draft status for over four years and was subsequently cancelled in late 2023. As a result, the corrective actions taken did not effectively address the issue, nor in a timely manner.
Enforcement:
Violation: Technical Specification 5.4.1, Procedures, requires that written procedures shall be established, implemented, and maintained as recommended in Regulatory Guide 1.33, Revision 2, Appendix A, February 1978. Regulatory Guide 1.33, Appendix A, Section 9.a, Procedures for Performing Maintenance, specifically addresses the need to have appropriate procedures for preventive maintenance that can affect the performance of safety-related equipment. The licensee developed procedure ER-AA-200, Preventive Maintenance Program, to implement that regulatory requirement, which incorporates utilization of PCM templates into the overall maintenance strategy for components.
Licensee procedure ER-AA-200, Preventative Maintenance Program, Revision 7, establishes requirements for preventative maintenance program development and implementation.
ER-AA-200, step 1.1 states, in part, the purpose of the preventative maintenance program, using the Performance Centered Maintenance (PCM) maintenance strategy analysis tools and other processes, is to maintain plant structures, systems, and components at an appropriate state of reliability. Step 4.3.5 states, in part, the PCM template is to be used as the starting point for the development of the maintenance strategy. Step 4.3.6 states, in part, all PCM template deviations have a technical basis documented by the site subject matter expert.
The PCM template for manual switches specified a time directed refurbishment or replacement interval for SBM switches classified as critical, low duty cycle, and mild environment (classification code D/4) every 20 years.
Contrary to the above, as of May 22, 2025, the licensee failed to refurbish or replace the General Electric switch block miniature (SBM) hand switch 1HS-AP044, switchgear 141Y feed from station auxiliary transformer (ABC1412). Specifically, the licensee was unable to identify any records indicating refurbishment or replacement, nor technical basis for PCM template deviation. Subsequently, the installed switch was believed to be over 40 years old.
Enforcement Action: This violation is being treated as a non-cited violation, 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 May 22, 2025, the inspectors presented the Age-Related Degradation Inspection results to Joseph Reda, Plant Manager, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
01503723
Unit 1 LPCS Injection Valve 1E21-F005 Will Not Open on
Demand
04/18/2013
01517000
LPCS Control Switch Equipment Classification Is Incorrect
05/23/2013
299109
2DG01A Hx South End Bell Degradation
11/21/2019
04332486
Delivery From BELLS Fuels Turned Away
04/03/2020
04379968 Report
Localized Corrosion Spots Identified on 1HP54A Piping
10/27/2020
04481044 Report
FM As-Found Results for 1B33-F060B Valve Internal
Inspection
2/27/2022
04481340 Report
1B33-F060A VT-3 Inspection Results
2/28/2022
04543774
1B DG Lock out on Differential Current
2/19/2022
04554672
2E12-F024B Will Not Electrically Open
2/15/2023
04555340
F/U to IR 04554142 MOV 2E12-F009
2/17/2023
04555344
2C41-F001A Failed to Open during LOS-SC-R3
2/17/2023
04557105
24 Failed to Close during LOS-AP-R2
2/24/2023
04695115
As-Found 0 DG Cooler Flow Outside Procedural Limit
08/07/2023
04702207
1HP55A-4" Line Replacement Issues
09/13/2023
04720620
1HP55A-4" Pipe Section Replacement
11/30/2023
04720620 Report
1HP55A-4" Pipe Section Replacement
11/30/2023
04767915
Loss of Unit 1 SAT due to OCB 1-13 Tripped on
Differential Current
04/20/2024
04802277
09/16/2024
04808661
Removed 2DG01A Hx End Bell Needs Weld Build Up and
Coating
10/11/2024
04809723
2B RHR Service Water Pump Leak
10/16/2024
04831327
Gap Identified in Aging Related Degradation Program
01/21/2025
Corrective Action
Documents
04836025
2B RHR WS Seal Further Degradation due to Pump
Running
2/10/2025
04842353
NRC ID: Housekeeping Observations
03/03/2025
04861832
NRC ARD Concern: Unidentified Streaks on EDG FOSTs
(1DO01T)
04/30/2025
71111.21N.04
Corrective Action
Documents
Resulting from
Inspection
04861833
NRC ARD Concern: Scaffold Erection Adjacent to U0 EDG 04/30/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
04862501
NRC Question: Component Classification
05/02/2025
04865215
NRC Question: SBM Switch Classification
05/13/2025
04865516
NRC ARD Concern: 241Y Switchgear Panel
05/13/2025
04865521
NRC ID: Housekeeping Issues Were Identified on AB
Walkdowns
05/13/2025
04865523
NRC Identified: U-1 250V Battery Discrepancies
05/13/2025
04865896
NRC Identified: U-1 250 V Battery Discrepancies
05/14/2025
Min Wall Calculations on Line 1RH90AB-4", 1DG27A-4",
03/10/2022
Engineering
Changes
L1R19 Lost Parts Evaluation
Engineering
Evaluations
EACE 1605603
EACE for 0VE03CB Fan Motor Failure
4406976
Reactor Recirculation (RR) Flow Control Valve (FCV)
Failed Internal Components and Subsequent Valve Body
Degradation
06/10/2021
EQ-LS098
General Electric SBM Control Switches Tab E Installation,
Maintenance, and Surveillance Schedule
LTR-NRC-22-14
Part 21 - Eaton Reversing (FVR) Contactors with
Mechanical Interlocks
04/11/2022
Miscellaneous
VETIP-J-0150,
Tab 009
Standby Battery Installation Instruction Vendor Manual
Preventive Maintenance Program
Equipment Classification
PCM Templates
Underground (Buried) Piping And Raw Water Integrity
Mangement Programs Guide
ER-AA-5400-
1001
Raw Water Piping Intregrity Management Guide
ER-AA-5400-
1002
Underground Piping And Tank Examination Guide
License Renewal Implementation Program
Procedures
Use of Operating Experience for License Renewal
Implementation / Aging Mangement
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
LEP-GM-175
Inspection/Replacement of GE Type SBM Switches
LMS-DO-01
Diesel Fuel Oil Storage Tank Cleaning
LOS-RH-Q1
RHR (LPCI) And RHR Service Water Pump and Valve
Inservice Test for Modes 1, 2, 3, 4 AND 5
103
LTS-200-11
Diesel Generator Cooling Heat Exchanger Thermal
Performance Monitoring
Scaffold Installation, Inspection, and Removal
NES-MS-04.1
Seismic Prequalified Scaffolds
Preventative Maintenance (PM) Database Revision
Requirements
Need Seismic Scaffold Installed in 0 DG FOST Room
06/16/2008
Unit 2 125 VDC Division 3 Battery Charger CAP/PC
Board/Fuses/Pots/TOGG
05/14/2014
25 VDC Division 3 Battery Charger CAP/PC
Board/Fuses/Pots/TOGG
09/10/2013
Unit 2 Division 3 125 VDC Battery Modified Test
2/12/2017
00069145-04, COM, (LR) 2DG01A Inspect, Clean and
Eddy Test D/G Hx, E: 2DG01A, N/A, H15
2/05/2019
25 VDC Division 3 Battery Charger CAP/PC
Board/Fuses/Pots/TOGG
05/24/2021
Unit 1 Division 3 125 VDC Battery Modified Test
03/01/2018
Unit 2 Division 3 125 VDC Battery Modified Test
05/25/2021
Unit 1 Division 3 125 VDC Battery Modified Test
09/19/2022
Replace Unit 2 Division 3 125 VDC Battery 2DC18E
04/25/2023
2DG01A Hx South End Bell Degradation
10/24/2024
Inspect Unit 1 Division 3 125 VDC Battery Per LES-DC-
101C
01/19/2023
(Change) Pump RHR Service Water
2/25/2018
2RH10 B RHR Service Water Pump (VT-2)
08/06/2024
2FC06 A FC Emergency Makeup Line - (VT-2)
05/13/2024
Work Orders
2DG02 LPCS And Cubicle Cooler CW (VT-2)
08/13/2024
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
2DG05 DG CW Buried Supply to Coolers (Flow M/U)
08/09/2024
L1R18 Contingency WO Needed for A1 RR FCV
2/13/2021
Disassemble Inspect Reassemble 1B33-F060
11/01/2022
PMG 1B33-F060B Perform Weld Build Up to Recondition
Defects
03/01/2022
1DG02 0 DG CW Suction & Discharge Piping (VT-2)
05/15/2023
2DG01 2A DG Cooling Water Piping (VT-2)
07/11/2024
2DG04 A DG CW Buried Return Piping (Unimpaired Flow)
08/02/2024
(LR) Various UT Ul CSCS Service Water Piping
(Sample 3)
03/27/2024