ML24130A241

Integrated Inspection Report 05200025/2024001 and 05200026/2024001

ML24130A241
Person / Time
Site:	Vogtle
Issue date:	05/13/2024
From:	Bradley Davis NRC/RGN-II
To:	Coleman J Southern Nuclear Operating Co
References
IR 2024001
Download: ML24130A241 (16)

Text

Jamie Coleman Director, Fleet Regulatory Affairs Southern Nuclear Operating Company, Inc.

3535 Colonnade Parkway, N 274 EC Birmingham, AL 35243

SUBJECT:

VOGTLE ELECTRIC GENERATING PLANT, UNIT 3 & 4 - INTEGRATED INSPECTION REPORT 05200025/2024001 AND 05200026/2024001

Dear Jamie Coleman:

On March 31, 2024, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Vogtle Electric Generating Plant, Unit 3 & 4. On April 29, 2024, the NRC inspectors discussed the results of this inspection with Mr. Patrick Martino, Vogtle Electric Generating Plant (VEGP)

Units 3 & 4 Site Vice President, and other members of your staff. The results of this inspection are documented in the enclosed report.

A licensee-identified violation which was determined to be of very low safety significance is documented in this report. We are treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2 of the Enforcement Policy.

If you contest the violation or the significance or severity of the violation documented in this inspection report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN:

Document Control Desk, Washington, DC 20555 0001; with copies to the Regional Administrator, Region II; the Director, Office of Enforcement; and the NRC Resident Inspector at Vogtle Electric Generating Plant, Unit 3 & 4.

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.May 13, 2024 J. Coleman 2 Sincerely, Bradley J. Davis, Chief Construction Inspection Branch 2 Division of Construction Oversight Docket Nos. 05200025 and 05200026 License Nos. NPF-91 and NPF-92

Enclosure:

As stated cc w/ encl: Distribution via LISTSERV Signed by Davis, Bradley on 05/13/24

ML24130A241 x Non-Sensitive x Publicly Available x SUNSI Review Sensitive Non-Publicly Available

OFFICE RII/DCO RII/DCO RII/DCO NAME J. Quinones J. Parent B. Davis DATE 5/13/24 5/13/24 5/13/24

U.S. NUCLEAR REGULATORY COMMISSION Inspection Report

Docket Numbers: 05200025 and 05200026

License Numbers: NPF-91 and NPF-92

Report Numbers: 05200025/2024001 and 05200026/2024001

Licensee: Southern Nuclear Operating Company, Inc.

Facility: Vogtle Electric Generating Plant, Unit 3 & 4

Location: Waynesboro, GA

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

Inspectors: J. Eargle, Senior Resident Inspector S. Egli, Senior Construction Inspector B. Griman, Resident Inspector T. Morrissey, Senior Resident Inspector J. Parent, Resident Inspector

Approved By: Bradley J. Davis, Chief Construction Inspection Branch 2 Division of Construction Oversight

Enclosure

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Vogtle Electric Generating Plant, Unit 3

& 4, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information. A licensee-identified non-cited violation is documented in report section: 71153.

List of Findings and Violations

No findings or violations of more than minor significance were identified.

Additional Tracking Items

None.

2 PLANT STATUS

Unit 3 began the inspection period at rated thermal power (RTP). On January 27, 2024, the unit entered Mode 3 (Hot Standby) due to a planned maintenance outage to perform repairs to passive core cooling system valves. The unit was returned to RTP on February 2, 2024, and remained at or near RTP for the remainder of the inspection period.

Unit 4 began the inspection period performing startup testing in Mode 5 (Cold Shutdown) and continued to perform startup testing in Mode 5 through Mode 3. On February 14, 2024, the unit entered Mode 2 (Startup) and attained initial criticality. Later, on February 14, 2024, the unit entered Mode 3 to perform repairs to main steam system valves. On February 21, 2024, the unit entered Mode 2 and continued to perform startup testing up to approximately 30 percent RTP.

On March 5, 2024, following startup testing that tripped the reactor, the unit entered Mode 3. On March 9, 2024, the unit entered Mode 2 and continued startup testing at various power plateaus for the remainder of the inspection period up to approximately 98 percent RTP.

INSPECTION SCOPES

Inspections were conducted using the appropriate portions of the inspection procedures (IPs) in effect at the beginning of the inspection unless otherwise noted. Currently approved IPs with their attached revision histories are located on the public website at http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/index.html. Samples were declared complete when the IP requirements most appropriate to the inspection activity were met consistent with Inspection Manual Chapter (IMC) 2515, Light-Water Reactor Inspection Program - Operations Phase. The inspectors performed activities described in IMC 2515, Appendix D, Plant Status, observed risk significant activities, and completed on-site portions of IPs. The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel to assess licensee performance and compliance with Commission rules and regulations, license conditions, site procedures, and standards.

REACTOR SAFETY

71111.01 - Adverse Weather Protection

Impending Severe Weather Sample (IP Section 03.02) (1 Sample)

(1) The inspectors evaluated the adequacy of the overall preparations and actions to protect risk-significant systems after a Flood Watch was issued by the National Weather Service on February 12, 2024.

71111.04 - Equipment Alignment

Partial Walkdown Sample [AP1000] (IP Section 03.01) (1 Sample)

The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:

(1) Unit 3 main control room emergency habitability system (VES), on January 19, 2024.

71111.05 - Fire Protection

3 Fire Area Walkdown and Inspection Sample [AP1000] (IP Section 03.01) (2 Samples)

(1) 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 unit 3 fire area:

• Fire Area 1210 AF 01: Class 1E DC and UPS System (IDS) spare battery room (fire zone: 1212 AF 12103), north auxiliary building, elevation 66'-6" corridor (fire zone: 1210 AF 12111), spare room (fire zone: 1212 AF 12112),

IDS spare battery charger room (fire zone: 1212 AF 12113) on January 16, 2024.

(2) 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 unit 4 fire area:

• Fire Area 1000 AF 01: Middle annulus (fire zone: 1200 AF 12341), upper annulus (fire zone: 1200 AF 12541), VES air storage area and operating deck staging area (fire zone: 1250 AF 12555), passive containment cooling system (PCS) valve room (fire zone: 1270 AF 12701) on March 15, 2024.

71111.06 - Flood Protection Measures

Flooding Sample (IP Section 03.01) (1 Sample)

(1) The inspectors evaluated internal flooding mitigation protections in the unit 4 shield building (upper annulus, room 12541) elevation 135'-3" on March 15, 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 unit 3 control room during turbine control manipulations to control primary (reactor coolant system) temperature on January 22, 2024. The inspectors observed and evaluated licensed operator performance in the unit 3 control room during unit 3 startup following planned maintenance outage on February 1, 2024.

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

(1) The inspectors observed and evaluated operator simulator training pertaining to abnormal operating procedure AOP-116, Loss of Spent Fuel Pool Cooling, and related event classification on March 4, 2024.

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management Sample [AP1000] (IP Section 03.01) (2 Samples)

(1) Unit 4 online risk management of planned passive core cooling system (PXS) freeze seal work activities during the week of January 21, 2024.

4 (2) Unit 3 PXS valve repair during the January 27 to February 1, 2024, planned maintenance outage.

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment [AP1000] (IP Section 03.01) (3 Samples)

(1) Condition report (CR) 11036857 on January 7, 2024. During the performance of 3-VES-OTS-17-001, Main Control Room Habitability Test, section 4.3.4 on unit 3, acceptance criteria was not met due to low flow rate of 60 standard-cubic-feet-minute (scfm) and pressure 114 pounds per square inch gauge (psig).

(2) TE 1143766 on December 28, 2023. Per NMP-AD-031-GL01, Past Operability /

Functionality Review, a past operability review of unit 3 core makeup tank (CMT) 'B' was performed due to valve leak by of PXS valves.

(3) TE 1144728 on January 12, 2024. Unit 4 containment isolation valve, 4-FHS-MY-Y01, had leak by at 60 drops-per-minute.

71111.18 - Plant Modifications

Temporary Modifications and/or Permanent Modifications [AP1000] (IP Section 03.01 and/or 03.02) (1 Sample)

(1) Unit 3 engineering design change request (E&DCR) No. SV3-PXS-GEF-142, Addition of Manual Isolation Valves for PXS Test Header, on January 23, 2024.

71111.20 - Refueling and Other Outage Activities

Refueling/Other Outage Sample (IP Section 03.01) (2 Samples)

(1) The inspectors evaluated the unit 4 reactor startup following a planned maintenance outage to repair main steam supply valves to moisture separator reheater (MSR) "A" on February 21 and 22, 2024.

(2) The inspectors evaluated the unit 3 planned maintenance outage activities including the replacement and repair activities on the "A" and "B" PXS test header valves, from January 27 to February 1, 2024.

71111.24 - Testing and Maintenance of Equipment Important to Risk

Post-Maintenance Testing (PMT) [AP1000] (IP Section 03.01) (3 Samples)

(1) Type B local leak rate test of unit 4 fuel transfer tube per work order (WO)

SNC1696866 on January 24, 2024.

(2) VES valve position verifications and system flow tests following maintenance on the following unit 4 VES valves: 4-VES-V1 (main control room (MCR) alternate supply isolation), V5A (MCR supply solenoid operated valve (SOV)), V5B (MCR supply SOV), per WOs SNC1686443, SNC1686441, and SNC1686442, respectively, on January 24, 2024.

(3) Unit 3 leak check and valve stroke for PXS-V230A (core makeup tank 'A' fill valve) and V232A (accumulator 'A' fill valve), per WOs SNC1654493 and SNC1654496, respectively, on January 30, 2024.

5 Surveillance Testing [AP1000] (IP Section 03.01) (1 Sample)

(1) 3-IDSC-OTS-06-004, 92 Day Quarterly Surveillance Test of Division C 24-hour Class 1E Station Batteries 3-IDSC-DB-1A and 3-IDSC-DB-1B, on January 17, 2024.

Inservice Testing (IST) [AP1000] (IP Section 03.01) (1 Sample)

(1) 4-GEN-OTS-10-002, "Division B Quarterly Valve Stroke Test," for valve 4-PXS-V015A on March 6, 2024.

Reactor Coolant System Leakage Detection Testing [AP1000] (IP Section 03.01) (1 Sample)

(1) 3-RCS-OTS-17-001, "Reactor Coolant System and Main Steam Line Leak Determination," on February 15, 2024.

OTHER ACTIVITIES - BASELINE

71152A - Annual Follow-up Problem Identification and Resolution

Annual Follow-up of Selected Issues (Section 03.03) (1 Sample)

The inspectors reviewed the licensees implementation of its corrective action program related to the following issues:

(1) CR 10991917. Unit 3 accumulator A and B boron concentration outside of specification low.

71153 - Follow Up of Events and Notices of Enforcement Discretion

Event Report (IP Section 03.02) (1 Sample)

The inspectors evaluated the following licensee event reports (LERs):

(1) LER 05200025/2024-001-00, "Condition Prohibited by Technical Specification Limiting Condition of Operation 3.1.6 Control Bank Overlap Limits Exceeded Due to Inadequate Procedure Guidance" (ADAMS Accession No. ML24078A343). The inspection conclusions associated with this LER are documented in this report under Inspection Results Section 71153. This LER is Closed.

INSPECTION RESULTS

Licensee-Identified Non-Cited Violation 71153 This violation of very low safety significance was identified by the licensee and has been entered into the licensee corrective action program and is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.

Violation: This violation of very low safety significance was identified by the licensee, resulting in Licensee Event Report (LER) 2024-001-00, and has been entered into the licensee corrective action program and is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.

Violation: Vogtle unit 3 technical specification (TS) 5.4, Procedures, requires, in part, that

6 written procedures shall be established and maintained covering the applicable procedures recommended in Appendix A, to Regulatory Guide 1.33, Quality Assurance Program Requirements, of February 1978. Appendix A, section 8.b.(k) requires surveillance procedures for control rod operability. Procedure 3-GEN-OTS-17-002, 12 Hour Technical Specification Surveillance, Revision 1.20, is a control rod operability surveillance procedure.

Contrary to this, prior to identifying the issue on January 20, 2024, the licensee failed to establish and maintain surveillance procedure 3-GEN-OTS-17-002, 12 Hour Technical Specification Surveillance, Revision 1.20, for verifying that the rod control banks tip-to-tip overlap met the step limit (181 step) specified in the core operating limit report (COLR) as required by TS limiting condition operation (LCO) 3.1.6, Control Bank Insertion Limits. This resulted in the operation of the unit in a condition prohibited by TS prior to discovery. Upon discovery operators responded by entering LCO 3.1.6, Condition B, "Control bank sequence or overlap limits not met," and completed the required actions to verify shutdown margin and to restore the overlap to within limits. The issue was entered in the corrective action program on January 20, 2024. The procedure was revised to require operators to manually record rod position and calculate the tip-to-tip distance to verify that the overlap is within the COLR limits following control rod movements. Additionally, the surveillance procedure was completed satisfactorily.

Significance/Severity: Green. The inspectors assessed the significance of the finding using guidance in IMC 0609, Appendix A, "Significance Determination Process for Findings At-Power," and determined the finding to be of very low safety significance because there was adequate shutdown margin while the overlap requirement was not being met.

Corrective Action

References:

CRs 11041569 and 11041757

EXIT MEETINGS AND DEBRIEFS

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

• On April 29, 2024, the inspectors presented the integrated inspection results to Mr.

Patrick Martino, VEGP Units 3 & 4 Site Vice President, and other members of the licensee staff.

7 DOCUMENTS REVIEWED

Inspection Type Designation Description or Title Revision or Procedure Date 71111.01 Corrective Action CR 11049341 Procedure Change request AOP-901 02/12/2024 Documents CR 11049380 NRC Identified AOP Entry Conditions 02/12/2024 Resulting from CR 11049530 AOP-901 Not Entered When Symptoms/Entry Conditions 02/12/2024 Inspection Met Procedures 3-AOP-901 Acts of Nature Ver. 1.0 3-AOP-901-B Background Information for 3-AOP-901 Acts of Nature Ver. 1.0 4-AOP-901 Acts of Nature Ver. 1.0 4-AOP-901-B Background Information for 4-AOP-901 Acts of Nature Ver. 1.0 NMP-OS-017 Severe Weather Ver. 3.1 71111.04 Drawings APP-VES-M6-001 Piping and Instrumentation Diagram Main Control Room 11 Emergency Habitability System APP-VES-M6-002 Piping and Instrumentation Diagram Main Control Room 15 Emergency Habitability System Procedures 3-VES-SOP-001 Main Control Room Emergency Habitability System 2.0 71111.05 Corrective Action CR 11059628 NRC Walkdown: Multiple Observations 03/15/2024 Documents CR 11059682 Identified oil leak from 4-PCS-V002B MOV 03/16/2024 Resulting from CR 11059687 Multiple Issues with various Fire Extinguishers 03/16/2024 Inspection Drawings APP-1010-AF-001 Fire Area Drawing, Nuclear Island, Plan AT El. 66'-6" 5 APP-1030-AF-001 Fire Area Drawing Nuclear Island Plan El. 100'-0" & 107'-2"6 APP-1050-AF-001 Fire Area Drawing Nuclear Island Operating Deck El. 135'-5 3"

APP-1050-AF-002 Fire Area Drawing Nuclear Island Partial Plan El. 153'-0"5 App-1070-AF-001 Fire Area Drawing Nuclear Island Plan at El. 160'-6" & 284'-5 10" B-GEN-ENG-008-Fire Equipment Impairments Fire Barrier Sketches 4.1 GL01 Procedures B-FPS-MMM-004 Portable Fire Extinguishers and Fire Hose Stations Visual 7.0 Inspection B-GEN-ENG-008 Fire Equipment Functionality and Fire Protection 8.1 Impairments (FPI) Requirements NMP-ES-035-017 Fleet Fire Doors Functional Inspection Governance and 2.0

8 Inspection Type Designation Description or Title Revision or Procedure Date Acceptance Criteria Work Orders SNC1732503 Replace Door Handle 4-12541-D04 0 SNC1743690 NRC Walkdown: Multiple Observations Inspect and Repair 0 Ladder Ground and Clamp.

71111.06 Calculations APP-PCS-M3C-PCS Minimum Cooling Water Flow Rates and Tank Sizing 5 015 APP-PCS-M3C-PCS Annulus Drain Sizing Calculation 2 162 Corrective Action CR 11059628 NRC Walkdown: Multiple Observations 03/15/2024 Documents CR 11059744 Debris identified within floor drains (under covers). 03/16/2024 Resulting from CR 11063167 NRC identified typographical errors in calculation APP- 03/28/2024 Inspection PCS-M3C-162 IR-2024-3367 Apparent typographical error identified during NRC 03/28/2024 inspection.

Drawings APP-1050-AF-001 Fire Area Drawing Nuclear Island Operating Deck El. 135'-5 3"

APP-1070-AF-001 Fire Area Drawing Nuclear Island Plan at El. 160'-6" & 284'-5 10" Miscellaneous APP-GW-G1-001 AP1000 Plant Design Criteria 4 Work Orders SNC1743701 NRC walkdown #6 replace drain cover removed from floor 0 in PCS Valve Room, 1.

71111.11Q Miscellaneous AP-LT-C-SG-Simulator Guide 1.0 EAL_QS12 Procedures 3-AOP-104 Rod Control System Malfunction 2.0 3-AOP-116 Loss of Spent Fuel Pool Cooling 3.0 3-GOP-302 Reactor Startup Mode 3 to Mode 2 2.0 71111.13 Corrective Action CR 11037481 Continuous learning from Freeze Seal 01/09/2024 Documents CR 11043021 Continuous learning from Freeze Seal and 3-PXS-V0224a 01/24/2024 install.

Miscellaneous Risk-Based Analysis from Risk Informed Engineering -

based on Unit 3 plant configuration for 1/23/2024.

Procedures NMP-AD-025 Quality Assurance and Non-Quality Assurance Records Ver. 14.3 Administration NMP-DP-001 Operational Risk Awareness Ver. 25.0

9 Inspection Type Designation Description or Title Revision or Procedure Date NMP-DP-001-F02 PXS Test Header Troubleshooting Plan Ver. 1.0 NMP-GM-031 On-Line Configuration Risk Management Program Ver. 9.4 NMP-GM-031-001 Online Maintenance Rule (a)(4) Risk Calculations Ver. 8.0 SV0-PRA-GSC-AP1000 Plant PRA, Shutdown Defense-In-Depth Risk A 383 Monitor Model Notebook Work Orders SNC1673896 3-PXS-V224A installation per Rev. 1 of 0 SNC1668087DECP.

SNC1675903 3-PXS-V224A Freeze Seal installation/removal. 0 SNC1705294 PXS Freeze Seal installation/removal for PMO. 0 71111.15 Corrective Action CR 11033845 Conditions inside Unit 4 Containment Identified during NRC 12/23/2023 Documents closeout inspection walkdown.

CR 11034299 Tech Spec 3.5.2 'B' Entered Due to Core Make Up Tank A 12/27/2023 Boron Concentration Below Tech Spec Limit.

CR 11036857 Failed to meet acceptance criteria for 3-VES-OTS-17-001 01/07/2024 CR 11038486 CR: 11033845 identified that there was water dripping from 01/11/2024 the fuel transfer tube into refueling cavity.

Drawings APP-PXS-M6-003, Piping And Instrumentation Diagram Passive Core Cooling Rev. 14 Sheet 1 of 1 System Engineering SVP_SVO_230346 Response to TE 1144360 - Vogtle Unit 3 Main Control 01/23/2024 Evaluations Room Habitability System (VES) Air Bank Supply Flow Deviation Evaluation TE 1143766 Post Operability Review of CMT A [B] Per NMP-AD-031-12/28/2023 GL01 TE 1144728 CR: 11033845 identified that there was water dripping from 01/12/2024 the fuel transfer tube into refueling cavity.

VNP-3-24-001 Operational Decision-Making Issue Worksheet 1/18/2024 Operability 11036857-Unit3-Operability Determination for CR# 11036857 01/23/2024 Evaluations ODS Procedures NMP-AD-012 Operability Determinations Ver. 16.1 NMP-AD-031-Past Operability/Functionality Review Ver. 1.0 GL01 NMP-ES-077 Processing ASME Class 2 and 3 Pressure Boundary Ver. 7.0 Integrity Challenges Work Orders SNC1696866 Correct boric acid leak at transfer tube 4-FHS-B01 0

10 Inspection Type Designation Description or Title Revision or Procedure Date 71111.18 Engineering E&DCR SV3-PXS-Addition of Manual Isolation Valves for PXS Test Header 0 Changes GEF-142 (TE 1143127)

SNC1668087 PXS Test header Isolation valve for Accumulator A and 2 CMT A Work Orders SNC1673896 3-PXS-V224A installation per Rev. 2 of SNC1668087DECP 71111.20 Calculations NMP-RE-019 Beacon 7 Estimated Critical Condition Calculation 02/15/2024 Corrective Action CR 11034299 Tech Spec 3.5.2 'B' entered due to Core Make Up Tank A 12/27/2023 Documents Boron Concentration below Tech Spec Limit CR 11053992 U4 Turbine Trip during initial synchronization 02/26/2024 Corrective Action CR 11044208 NRC Identified Deficiency - U3 Containment Elevator 01/28/2024 Documents Condition Resulting from CR 11044209 Miscellaneous Items Found on U3 Polar Crane 01/28/2024 Inspection Miscellaneous Vogtle Electric Generating Plant (VEGP) Unit 3 - Pressure 0.1 and Temperature Limits Report (PTLR)

Operability TE 1143766 Past Operability review of CMT A [B] per NMP-AD-031-12/28/2023 Evaluations GL01 Procedures 3-GOP-101 Power Operations Above 25% Power 4.2 3-GOP-202 Plant Shutdown 25% Power To Mode 3 1.0 3-GOP-306 Plant Startup Mode 2 to 25% Power 2.0 3-PXS-CSP-002 Sampling the Accumulators 3.1 3-PXS-CSP-003 Sampling The Core Makeup Tanks 3.0 3-PXS-OTS Chemistry Control of The Accumulators 1.0 001 3-PXS-OTS Chemistry Control of the Core Makeup Tanks 2.0 002 4-CNS-SOP-001 Containment System 2.0 4-GEN-ITPS-632 Load Swing Test Startup Test Procedure 1.0 4-GOP-301-002 Mode 2 Change Checklists 1.2 4-GOP-302 Reactor Startup Mode 3 to Mode 2 2.0 4-GOP-306 Plant Startup Mode 2 to 25% Power 3.0 4-ZAS-MEM-002 Main Generator Initial Synchronization Testing 1.0 NMP-RE-008-F01 Detailed Reactivity Management Plan - Restoration of Core 1/08/2024 Makeup Tank (CMT) Conditions

11 Inspection Type Designation Description or Title Revision or Procedure Date NMP-RE-008-F02 Simplified Reactivity Management Plan - Reactor Trip & 02/15/2024 Plant Recovery Following Low Power Physics Testing 71111.24 Corrective Action CR 11056982 4-PXS-V015A stroked faster than IST low limit. 03/06/2024 Documents TE 1149796 4-PXS-V015A stroked faster than IST low limit. 03/07/2024 Procedures 3-IDSC-OTS 92 Day Surveillance Test of Station Batteries 3-IDSC-DB-5.1 004 1A and 3-IDSC-DB-1B 3-PXS-OTS Passive Core Cooling System Train A Valves Stroke Tet 2.0 001 3-RCS-OTS Reactor Coolant System And Main Steam Line Leak 5.0 001 Determination 4-CNS-OTS Type B Local Leak Rate Testing 1.0 002 4-VES-OTS Main Control Room Emergency Habitability System Valve 1.0 001 Position and Operability Check NMP-OS-009 RCS Unidentified Leakage Monitoring Program 6.0 Work Orders SNC1571874 (3M) DIV B Quarterly Stroke Test (PXS-V015A) 0 SNC1654493 Disassemble, Inspect, and Replace Any Internal Wear parts 01/30/2024 in PXS Components SNC1654496 Disassemble, Inspect, and Replace Any Internal Wear 01/30/2024 Parts PXS-V232A SNC1686441 PMT for the disassemble / rework / reassemble of 4-VES- 0 V005A SNC1686442 PMT for the disassemble / rework / reassemble of 4-VES- 0 V005B, MCR Supply SOV SNC1686443 PMT for the replacement of valve 4-VES-V001 0 SNC1696866 Correct Boric Acid Leak at Transfer Tube 4-FHS-B01 0 71152A Corrective Action 10991917 Accumulator A & B Out of Spec Low for Boron 07/28/2023 Documents Work Orders SNC1527427 Repair 3-PSS-V012A Leakby 07/31/2023 71153 Corrective Action 11041569 LCO 3.1.6 Overlap Limits Not Met During 12-hr TS SR 01/20/2024 Documents 11041757 Surveillance Signed Off as Satisfactory When the Actual 01/21/2024 Tip to Tip Distance was outside COLR Engineering SNC1714794 DRCS Overlap Logic, NAPs, Urgent Alarm 03/01/2024 Changes

12 Inspection Type Designation Description or Title Revision or Procedure Date Engineering 1145572 Past Operability Eval Surveillance Signed Off as 01/21/2024 Evaluations Satisfactory When Outside COLR 1145785 Attachment 6 - IRT Report Outline 03/23/2024 1145968 Perform MREVAL for CR 11041569 Against 3-PLS 02/19/2024 1149707 Submit Unit 3 LER 2024-001-00 to NRC 03/06/2024 Miscellaneous Licensee Event Condition Prohibited by Technical Specification Limiting 03/18/2024 Report 2024-001-Condition of Operation 3.1.6 Control Bank Overlap Limits 00 Exceeded Due to Inadequate Procedure Guidance

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