Text

Integrated Inspection Report 05000338/2024002 and 05000339/2024002
	ML24214A076
Person / Time
Site:	North Anna
Issue date:	08/02/2024
From:	Matthew Fannon; NRC/RGN-II/DRP/RPB4
To:	Carr E; Virginia Electric & Power Co (VEPCO)
References
	IR 2024002
	Download: ML24214A076 (12)
	v • d • e

SUBJECT:

NORTH ANNA POWER STATION, UNITS 1 AND 2 - INTEGRATED INSPECTION REPORT 05000338/2024002 AND 05000339/2024002

Dear Eric S. Carr:

On June 30, 2024, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at North Anna Power Station, Units 1 and 2. On July 23, 2024, the NRC inspectors discussed the results of this inspection with Lisa Hilbert, 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, Matthew S. Fannon, Chief Reactor Projects Branch 4 Division of Reactor Projects Docket Nos. 05000338 and 05000339 License Nos. NPF-4 and NPF-7

Enclosure:

As stated

Inspection Report

Docket Numbers: 05000338 and 05000339

License Numbers: NPF-4 and NPF-7

Report Numbers: 05000338/2024002 and 05000339/2024002

Enterprise Identifier: I-2024-002-0017

Licensee: Dominion Energy

Facility: North Anna Power Station, Units 1 and 2

Location: Mineral, VA

Inspection Dates: April 01, 2024 to June 30, 2024

Inspectors: K. Carrington, Senior Resident Inspector A. Ruh, Senior Reactor Inspector D. Turpin, Resident Inspector

Approved By: Matthew S. Fannon, Chief Reactor Projects Branch 4 Division of Reactor Projects

Enclosure

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at North Anna Power Station, Units 1 and 2, 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 shut down for refueling outage 1R30. The unit was restarted on April 7, 2024, and returned to rated thermal power (RTP) on April 11, 2024. On May 29, 2024, the unit experienced a high neutron flux rate, automatic reactor trip from 100 percent RTP. The unit was restarted on May 31, 2024, and returned to rated thermal power on June 1, 2024, where it continued to operate for the remainder of the inspection period.

Unit 2 operated at or near 100 percent RTP for the entire 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.

REACTOR SAFETY

71111.04 - Equipment Alignment

Partial Walkdown Sample (IP Section 03.01) (4 Samples)

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

(1) Unit 2, 'B' service water system during 'A' service water system testing, on April 9, 2024

(2) Unit 2, 'C' charging system following system testing, on April 29, 2024

(3) Unit 2, 'A' main control room chiller system following system testing, on April 30, 2024

(4) Unit 1, 'B' low head safety injection pump during 'A' low head safety injection system testing, on May 6, 2024

71111.05 - Fire Protection

Fire Area Walkdown and Inspection Sample (IP Section 03.01) (7 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 11, auxiliary building, 259' elevation, gas stripper and low level liquid waste rooms, on April 10, 2024

(2) Fire Zone 14A-1, Unit 1, turbine-driven auxiliary feedwater pump room, on June 28, 2024

(3) Fire Zone 14A-2, Unit 2, turbine-driven auxiliary feedwater pump room, on June 28, 2024

(4) Fire Zone 14B-1, Unit 1, motor-driven auxiliary feedwater pump room, on June 28, 2024

(5) Fire Zone 14B-2, Unit 2, motor-driven auxiliary feedwater pump room, on June 28, 2024

(6) Fire Zone 9A-2, Unit 2, 'H' emergency diesel generator (EDG), on June 28, 2024

(7) Fire Zone 9B-2, Unit 2, 'J' EDG, on June 28, 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 May 23, 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) (2 Samples)

(1) The inspectors observed and evaluated licensed operator performance in the main control room during the Unit 1 startup following refueling outage 1R30, on April 6-7, 2024.

(2) The inspectors observed and evaluated licensed operator performance in the main control room during the Unit 1 startup following a forced outage, on May 31, 2024.

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

(1) The inspectors observed licensed operator requalification training scenario SXG-1 in the control room simulator, on May 21, 2024.

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management Sample (IP Section 03.01) (6 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 2, elevated risk associated with planned maintenance and testing on the 2J EDG system, the main control room heating and ventilation system, and the 2B motor-driven auxiliary feedwater pump, the week of April 15, 2024

(2) Shared station blackout diesel generator emergent troubleshooting due to load swings, emergent troubleshooting associated with security uninterruptible power supply inverter trip, and Unit 1 'A' solid state protection system surveillance, the week of May 3, 2024

(3) Unit 1, elevated risk associated with planned maintenance and testing on the 1B charging pump, the Unit 1 'A' auxiliary feedwater pump loss of power test, and the Unit 2 'B' low head safety injection pump test, the week of May 13, 2024

(4) Elevated and aggregate risk associated with the shared fire protection system isolation due to piping rupture, the week of June 10, 2024

(5) Elevated and aggregate risk associated with Unit 2, 'B' charging pump piping replacement, shared 'A' underground diesel fuel oil storage tank inspection, and transmission company hot weather alert, the week of June 17, 2024

(6) Shared 'A' service water header planned maintenance outage, 6-ton carbon dioxide system inadvertent pressurization and impact on Unit 2, 'J' EDG, and Unit 1, letdown rad monitor emergent maintenance, on June 27, 2024

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment (IP Section 03.01) (9 Samples)

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

(1) Condition report (CR)1256743, 2-FW-E-9B (2-FW-P-3B) Oil Cooler Leak Degrading, on April 16, 2024

(2) CR1248156, 1H OCS #8 Fuel Pump Leaking Approximately 5-30 DPM, on May 7, 2024

(3) CR1219870, 1-CH-MOV-1267A Open Weak Link Exceeded and Minimum Required Thrust Not Obtained, on May 18, 2024

(4) CR1261394, Fire Protection Piping Rupture Near Above Ground Fuel Oil Storage Tank, on June 7, 2024

(5) NRC Question Related to BDB-GEN-2A Flexible Strategy Diesel Generator Test Not Being Conducted at Full Load (100%), on June 10, 2024

(6) CR1256999, 2J EDG Declared Inoperable Due to Loss of Excitation, and CR1257118, 2-EE-EG-2J EDG K1 Relay Found to be Not Functioning Properly, on June 14, 2024

(7) CR1261941, 01-EG-LI-100A Indication Became Erratic During Filling, on June 14, 2024

(8) CR1252352, 1-RC-HSS-106 Melted Reservoir, on June 14, 2024

(9) CR1238450, Extent of Condition Review of Level Control Valve Failure, on June 21, 2024

71111.20 - Refueling and Other Outage Activities

Refueling/Other Outage Sample (IP Section 03.01) (1 Sample)

(1) The inspectors evaluated Unit 1 refueling outage [1R30] activities, from April 1, 2024 to April 7, 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) (8 Samples)

(1) 1-PT-77.13B, Unit 1, 'B' main control room chiller test, following planned maintenance under work order (WO)59203418747, on April 9, 2024

(2) 2-OP-31.2, Unit 2, 'B' motor-driven auxiliary feedwater pump test, following lube oil cooler gasket replacement under WO59203417007, on April 17, 2024

(3) 2-PT-82.2B, Unit 2, 'J' diesel generator test (simulated loss of offsite power test)following K1 excitation relay replacement under WO59203427559, on April 19, 2024

(4) 'A' service water return header motor operated valve SW-MOV-223B as-left diagnostic test following valve seat repair under WO59203405984, on June 14, 2024

(5) 0-ICM-XX-AOV-001, Unit 2, 'B' charging pump lube oil cooler service water temperature control valve diagnostic test, following piping replacement under WO59203403947, on June 14, 2024

(6) 2-PT-14.2B, Unit 2, 'B' charging pump test, following piping replacement (ALXN)under WO59203403949, on June 15, 2024

(7) 0-ICP-EG-L-100A, 'A' diesel fuel oil storage tank level indication 0-EG-L-100A calibration, following troubleshooting and adjustment, on June 15, 2024

(8) 1-PT-77.13B, Unit 1, 'B' main control room chiller test, following compressor swap under WO59203430640, on June 19, 2024

Surveillance Testing (IP Section 03.01) (3 Samples)

(1) Reactor physics testing during Unit 1 startup from refueling outage 1R30, on April 7, 2024

(2) 1-PT-57.1A, Emergency Core Cooling Subsystem - Low Head Safety Injection Pump (1-SI-P-1A), on May 6, 2024

(3) 2-PT-57.1B, Emergency Core Cooling Subsystem - Low Head Safety Injection Pump Test (2-SI-P-1B), on May 16, 2024

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

(1) 1-PT-75.2A.1, 1-SW-P-1A Test (ISI) Comprehensive Test, on April 9, 2024

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

(1) 0-MPM-2000-10, Beyond Design Basis 480 VAC Generator 4-Year Functional Testing, 0-BDB-GEN-2A and 0-BDB-GEN-2B, on June 10, 2024

71114.06 - Drill Evaluation

Required Emergency Preparedness Drill (1 Sample)

(1) The inspectors observed emergency preparedness drill NJUN24DR, on June 11, 2024.

Additional Drill and/or Training Evolution (1 Sample)

The inspectors evaluated:

(1) Licensed operator requalification training and drill exercise performance scenario in the control room simulator SXG-4, on May 14,

OTHER ACTIVITIES - BASELINE

===71151 - Performance Indicator Verification

The inspectors verified licensee performance indicator submittals listed below:

MS07: High Pressure Injection Systems (IP Section 02.06)===

Main article: IP 71151

(1) Unit 1: April 1, 2023 to March 31, 2024

(2) Unit 2: April 1, 2023 to March 31, 2024

71152A - Annual Follow-up Problem Identification and Resolution Annual Follow-up of Selected Issues (Section 03.03)

Main article: IP 71152

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

(1) CR1240021, Wrong wire lifted during 2-PT-36R AMSAC functional test resulting in unsat PT, on May 28, 2024

(2) CR1250949, Missed TSC HVAC MRULE Evals, on May 28, 2024

(3) CR1238450, Letdown level control valve 1-CH-LCV-1460A failed closed, on June 18, 2024

71152S - Semiannual Trend Problem Identification and Resolution Semiannual Trend Review (Section 03.02)

Main article: IP 71152

(1) The inspectors reviewed the licensees corrective action program to identify potential trends in resolving deficiencies identified in CR1237987, CR1252783, CR1252238, CR1252232, CR1219870, CR1253774, CR1253091, and CR1253028, during motor-operated valve testing, that might be indicative of a more significant safety issue.

71153 - Follow Up of Events and Notices of Enforcement Discretion Event Follow up (IP Section 03.01)

Main article: IP 71153

(1) The inspectors evaluated the Unit 1 high neutron flux rate, automatic reactor trip, and the licensees response, on May 29,

INSPECTION RESULTS

Observation: Trend Associated with Motor-Operated Valves (MOVs) Exceeding 71152S As-Found Thrust Values The inspectors performed a semi-annual trend review sample of several CRs written between February 2023 and March 2024 that were associated with safety-related MOVs exceeding their as-found thrust acceptance criteria during testing. The inspectors performed this review to determine 1) if a trend existed, 2) that the identified issues were not indicative of a more significant safety concern, and 3) that the identified issues were captured in the licensee's corrective action program and trended.

Of the eight CRs, the inspectors noted several requirements or acceptance criteria were unmet for various reasons. The inspectors noted the CRs documented the licensee's evaluations of the MOVs being outside their acceptance criteria and whether the valves' ability to perform their safety functions was impacted; however, the inspectors noted the cause for exceeding the acceptance criteria was not identified in all cases. The inspectors reviewed the licensee's evaluations and determined the overall impact of each valve exceeding its as-found thrust values. The inspectors found that in each case the licensee was able to justify operability of the MOVs and had the following observations related to their review:

In the case of CR1237987, documenting operability of 2-CH-MOV-2381, the inspectors noted the licensee was able to show that the MOV components can withstand additional stress for numerous cycles before breaking.

In the case of CR1252783 associated with 1-SI-MOV-1867C, the inspectors noted the licensee was able to justify operability based on available margin.

In the case of the service water MOVs (2-SW-MOV-206B & 202B) associated with CR1252238, and CR1252232, the inspectors found that the MOV torque ratings for the actuator gearbox and valve internals were exceeded, however the licensee evaluated the use and acceptability of using higher torque ratings.

With respect to CR1219870, associated with MOV 1-CH-MOV-1267A, the inspectors noted that the licensee lowered the MOV acceptance criteria and with the lowered acceptance criteria there was a resultant extremely low margin for this valve's passive failure mitigation function.

In the case of 1-CH-MOV-1289B associated with CR1253774, the inspectors noted that the licensee's test program identified that an assumed calculational parameter was exceeded and appropriate actions were taken to update the calculation ME-3022 with the new information and that positive margins were maintained.

With respect to 1-CH-MOV-1269B associated with CR1253091, the inspectors found that the licensee's evaluation of the wink link stress of disc lifter/disc arm and slight overstress appeared reasonable.

In the case of 1-FW-MOV-150A associated with CR1253028, the inspectors found that structural limits were not exceeded, and the issue affected the non-safety, open direction of the valve.

While no CRs were found documenting a licensee-identified trend on exceeding the as-found thrust acceptance requirements, the inspectors acknowledge the licensee's corrective actions to address these issues such as performing valve maintenance and repairs to increase the amount of safety margin associated with the valves. Specifically, in each instance where acceptance criteria were not met, the licensee planned or completed corrective actions or performed an engineering evaluation to justify the available margin of each MOV. The inspectors ultimately did not determine that the negative trend constituted a more significant safety concern based on their review.

EXIT MEETINGS AND DEBRIEFS

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

On July 23, 2024, the inspectors presented the integrated inspection results to Lisa Hilbert, Site Vice President, and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection Type Designation Description or Title Revision or

Procedure Date

71111.15 Operability ODCA8587871 4

Evaluations

71111.24 Calculations CALC 59-01-PT-Emergency Core Cooling Subsystem Low Head Safety 2

57.1A Injection Pump 1-SI-P-1A

ME-0628 Minimum Delivered LHSI Flow for LB LOCA Analysis and 1

Acceptance Criteria for LHSI Pump Operability Verification

Testing - North Anna 1 & 2

Drawings 11715-FM-096A Flow/Valve Operating Numbers Diagram Safety Injection 43

System North Anna Power Station Unit 1 Virginia Power

Procedures 1-PT-57.1A Emergency Core Cooling Subsystem - Low Head Safety 64

Injection Pump (1-SI-P-1A)

71152S Calculations ME-0317 Service Water Motor Operated Valve Operating Torque 0

Requirements

ME-0883 EPRI Performance Prediction Methodology (PPM) Thrust 1

Calculation for North Anna Aloyco Split-Wedge Gate Valves

ME-3006 JOG Calculation of Required Thrust Settings and Margin for 0

the Charging Pump Suction MOVs

ME-3006 Recalculating Required Thrust Settings and Margin for the 0

Addendum A Charging Pump Suction MOVs Using the Updated

Differential Pressure Across the Subject Valves

ME-3078 JOG Calculation of Required Thrust Settings and Margin for 2

59-01-SI-MOV-1867C

ME-3158 JOG Calculation of Required Thrust Settings and Margin for 2

59-02-CH-MOV-2381

WL-128 Weak-Link Report CN Report No. WL-128 3

Corrective Action 1237987,

Documents 1252783,

252238,

252232,

219870,

253774,

253091,