Text

Biennial Problem Identification and Resolution Inspection Report 05000424/2025010 and 05000425/2025010
	ML25167A082
Person / Time
Site:	Vogtle
Issue date:	06/20/2025
From:	Alan Blamey; NRC/RGN-II/DORS
To:	Coleman J; Southern Nuclear Operating Co
References
	IR 2025010
	Download: ML25167A082 (15)
	v • d • e

Jamie Coleman

Regulatory Affairs Director

Southern Nuclear Operation Company, Inc.

3535 Colonnade Parkway

Birmingham, AL 35243

SUBJECT:

VOGTLE ELECTRIC GENERATING PLANT, UNITS 1 AND 2 - BIENNIAL

PROBLEM IDENTIFICATION AND RESOLUTION INSPECTION REPORT

05000424/2025010 AND 05000425/2025010

Dear Jamie Coleman:

On June 18, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed a problem

identification and resolution inspection at your Vogtle Electric Generating Plant, Units 1 and 2

and discussed the results of this inspection with Jamaal Mayweather and other members of

your staff. The results of this inspection are documented in the enclosed report.

The NRC inspection team reviewed the stations problem identification and resolution program

to confirm that the station was complying with NRC regulations and licensee standards. Based

on the samples reviewed, the team determined that your program complies with NRC

regulations and applicable industry standards such that the Reactor Oversight process can

continue to be implemented.

The team also evaluated the stations effectiveness in identifying, prioritizing, evaluating, and

correcting problems, reviewed licensee audits and self-assessments, and its use of industry and

NRC operating experience information. The results of these evaluations are in the enclosure.

Finally, the team reviewed the stations programs to establish and maintain a safety-conscious

work environment and interviewed station personnel to evaluate the effectiveness of these

programs. Based on the teams observations and the results of these interviews, the team found

no evidence of challenges to your organizations safety-conscious work environment. Your

employees appeared willing to raise nuclear safety concerns through at least one of the several

means available.

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 II; the Director, Office of Enforcement; and the NRC Resident Inspector at

Vogtle Electric Generating Plant, Units 1 and 2.

June 20, 2025

J. Coleman

2

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 II; and the NRC

Resident Inspector at Vogtle Electric Generating Plant, Units 1 and 2.

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,

Alan J. Blamey, Chief

Reactor Projects Branch 3

Division of Operating Reactor Safety

Docket Nos. 05000424 and 05000425

License Nos. NPF-68 and NPF-81

Enclosure:

As stated

cc w/ encl: Distribution via LISTSERV

Signed by Blamey, Alan

on 06/20/25

ML25167A082

x

SUNSI Review

x

Non-Sensitive

Sensitive

x

Publicly Available

Non-Publicly Available

OFFICE

RII/DORS

NAME

C. Scott

A. Blamey

DATE

6/18/25

6/20/25

Enclosure

U.S. NUCLEAR REGULATORY COMMISSION

Inspection Report

Docket Numbers:

05000424 and 05000425

License Numbers:

NPF-68 and NPF-81

Report Numbers:

05000424/2025010 and 05000425/2025010

Enterprise Identifier:

I2025-010-0049

Licensee:

Southern Nuclear Operation Company, Inc.

Facility:

Vogtle Electric Generating Plant, Units 1 and 2

Location:

Waynesboro, GA

Inspection Dates:

April 21, 2025 to May 08, 2025

Inspectors:

T. Fanelli, Senior Resident Inspector

M. Kay, Resident Inspector

C. Scott, Senior Project Engineer

B. Truss, Resident Inspector

Approved By:

Alan J. Blamey, Chief

Reactor Projects Branch 3

Division of Operating Reactor Safety

2

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees

performance by conducting a biennial problem identification and resolution inspection at Vogtle

Electric Generating Plant, 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

Failure to Maintain Qualification of Digital Governors for Emergency Diesel Generators

Cornerstone

Significance

Cross-Cutting

Aspect

Report

Section

Mitigating

Systems

Green

NCV 05000424,05000425/2025010-01

Open/Closed

[H.6] - Design

Margins

71152B

The team identified a Green non-cited violation (NCV) of 10 CFR 50, Appendix B, Criterion III,

Design Control, for the failure to verify that modifications to the qualified configuration of the

emergency diesel generator (EDG) governor would continue to assure acceptable

performance when exposed to electromagnetic interference (EMI).

Additional Tracking Items

None.

3

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.

OTHER ACTIVITIES - BASELINE

71152B - Problem Identification and Resolution

Biennial Team Inspection (IP Section 03.04) (1 Sample)

4

(1)

The inspectors performed a biennial assessment of the effectiveness of the licensees

Problem Identification and Resolution program, use of operating experience, self-

assessments and audits, and safety conscious work environment.

Problem Identification and Resolution Effectiveness: The inspectors assessed

the effectiveness of the licensees Problem Identification and Resolution

program in identifying, prioritizing, evaluating, and correcting problems. The

inspectors also conducted a five-year review of the diesel generators, nuclear

service cooling water, and safety injection. Also, as part of the assessment,

the inspectors reviewed corrective actions for the following non-cited violations

(NCVs), findings (FIN), and licensee-identified violations (LIVs):

o

2023002-01. Failure to Maintain Assessment Capability of

Containment Hydrogen Monitors.

o

2023002-02. Emergency Diesel Generator Control Air Pressure Gauge

not Calibrated.

o

2023011-01. Failure to Implement Maintenance Instructions for

Component Cooling Water Pump.

o

2023011-02. Engineered Safety Features (ESF) Chillers Performance

Data Not Considered During §50.69 Periodic Review.

o

2023011-03. Performance Data for RISC-3 Structures, Systems, and

Components Scoped-Out of the Maintenance Rule (§50.65) not

considered during §50.69 Periodic Reviews.

o

2023004-01. Unit 1 Design Control: Inadequate Equivalency

Evaluation.

o

2024403-01. Failure to Review Audit Logs on Badging Workstations.

o

2024401-01. Safeguards Information (SGI) Laptop Left Unattended in

the Protected Area.

o

2024004-02. Failure to Correct a Condition Adverse to Quality.

Resulted in Premature Failures of Regulating Transformers.

o

2024004-01. Failure to Identify a Condition Adverse to Quality on 1E

Safety-Related 125 VDC Emergency Battery.

Operating Experience: The inspectors assessed the effectiveness of the

licensees processes for use of operating experience.

Self-Assessments and Audits: The inspectors assessed the effectiveness of

the licensees identification and correction of problems identified through

audits and self-assessments.

Safety Conscious Work Environment: The inspectors assessed the

effectiveness of the stations programs to establish and maintain a safety-

conscious work environment.

5

INSPECTION RESULTS

Assessment

71152B

Assessment

1) Corrective Action Program Effectiveness

Problem Identification: The inspectors determined that the licensee was effective in

identifying problems and entering them into the corrective action program (CAP) and that

there was a low threshold for entering issues into the CAP. This conclusion was based on a

review of the requirements for initiating condition reports as described in licensee procedure

NMP-GM002, "Corrective Action Program," version 19.0, and managements expectation

that employees were encouraged to initiate condition reports. Additionally, site management

was actively involved in the CAP and focused appropriate attention on significant plant

issues.

Problem Prioritization and Evaluation: The inspectors reviewed condition reports (CRs),

technical evaluations, and completed and/or planned work orders. With the exception noted

below, the inspectors concluded that problems were, generally, prioritized and evaluated in

accordance with licensee procedure NMP-GM002-001, "Corrective Action Program

Instructions," version 55.0. The inspectors determined that adequate consideration was given

to structures, systems, and/or component's operability and associated plant risk. The

inspectors determined that, in general, plant personnel had conducted cause evaluations in

accordance with licensees CAP procedures, as described in NMP-GM002-GL03, "Cause

Analysis and Corrective Actions Guidelines," version 37.0, and cause determinations were

appropriate, and considered the significance of the issues being evaluated.

Corrective Actions: The inspectors reviewed corrective action documents, interviewed

licensee staff, and verified completion of corrective actions. With the exception noted below,

the inspectors determined that, generally, corrective actions were timely, commensurate with

the safety significance of the issues, and effective, in that conditions adverse to quality (CAQ)

were corrected. The team determined that the licensee was generally effective in developing

corrective actions that were appropriately focused. The inspectors reviewed CRs and

effectiveness reviews, as applicable, to verify that the significant conditions adverse to quality

had not recurred. Effectiveness reviews for corrective actions to preclude repetition were

sufficient to ensure corrective actions were properly implemented and were effective. The

inspectors reviewed corrective action documents for NRC findings issued since the last

problem, identification, and resolution biennial inspection.

Based on the samples reviewed, the team determined that the licensees CAP complied with

regulatory requirements and self-imposed standards. The licensees implementation of the

CAP adequately supported nuclear safety.

2) Operating Experience

The team determined that the licensees processes for the use of industry and NRC operating

experience information were effective and complied with regulatory requirements and

licensee standards. The implementation of these programs adequately supported nuclear

safety. The team concluded that operating experience was adequately evaluated for

applicability and that appropriate actions were implemented in accordance with applicable

6

procedures.

3) Self-Assessments and Audits

The inspectors reviewed a sample of completed self-assessments and audits conducted by

both plant and nuclear oversight personnel. The inspectors determined that the licensee was

effective at performing self-assessments and audits to identify issues at a low level, properly

evaluated those issues, and resolved them commensurate with their safety significance. The

self-assessments and audits were adequately self-critical and performance-related issues

were being appropriately identified. The inspectors verified that CRs were created to

document areas for improvement and findings and verified that actions had been completed

consistent with those recommendations.

4) Safety Conscious Work Environment

The inspectors interviewed a sample of plant employees from various departments and with

varying roles/responsibilities within the organization. The inspectors determined that

employees (1) were willing to raise nuclear safety concerns to their supervisor/manager or

though the CAP, (2) were aware of alternative avenues for raising concerns such as the

Employee Concern Program (ECP), and (3) had not experienced retaliation for raising safety

concerns. Specifically, all individuals interviewed indicated that they would feel comfortable in

raising safety concerns. All individuals felt that their management was receptive to receiving

safety concerns and generally addressed them promptly and commensurate with the

significance of the concern. Most interviewees were aware of the licensee's ECP and stated

they would use the program, if necessary. When asked whether there have been any

instances where individuals experienced retaliation or other negative reaction for raising

safety concerns, all individuals interviewed stated that they had neither experienced nor

heard of an instance of retaliation at the site. To supplement these discussions, the team

reviewed the ECP case log and interviewed the ECP Coordinator to assess their perception

of the site employees' willingness to raise nuclear safety concerns. Also, the team reviewed a

sample of the most recent Nuclear Safety Culture Monitoring Panel meeting reports as well

as the results from the most recent biennial safety culture survey and self-assessment from

June 2024. The team determined that the processes in place to mitigate potential safety

culture issues were adequately implemented.

Failure to Maintain Qualification of Digital Governors for Emergency Diesel Generators

Cornerstone

Significance

Cross-Cutting

Aspect

Report

Section

Mitigating

Systems

Green

NCV 05000424,05000425/2025010-01

Open/Closed

[H.6] - Design

Margins

71152B

The team identified a Green non-cited violation (NCV) of 10 CFR 50, Appendix B, Criterion III,

Design Control, for the failure to verify that modifications to the qualified configuration of the

emergency diesel generator (EDG) governor would continue to assure acceptable

performance when exposed to electromagnetic interference (EMI).

Description: The team reviewed condition report (CR)10984893, Unit 2 Diesel Generator B

uncontrolled loading while performing Monthly Operability Test, and technical evaluation

(TE) 1132077, Past Operability Review: Unit 2 Diesel Generator B uncontrolled loading

during Operability Test. The TE documented an uncontrolled loading event during testing of

the emergency diesel generators in July of 2023. The event occurred after the installation of a

7

digital governor modification in March 2023.

Vogtle units 1 and 2 licensing basis requires the diesel governor components to be qualified;

to the range of voltage, frequency, load, electromagnetic interference, and other electrical

characteristics and installed in accordance with IEEE 323-1974, IEEE Standard-for

Qualifying Class 1E Equipment for Nuclear Power Generating Stations. Licensee procedure,

SN9604 Electromagnetic Interference (EMI) Qualification Requirements for Southern

Nuclear Power Plant Equipment states that Section 5 of Electric Power and Research

Institute (EPRI) Technical Report (TR)-102323, Rev. 3, Guidelines for Electromagnetic

Interference Testing of Power Plant Equipment should be used to determine required test,

ranges, and testing level. Vogtle received the digital governor from Engine Systems Inc. (ESI)

and ESI contracted Analysis and Measurement Services (AMS) to qualify the governor for

EMI capabilities in accordance with EPRI TR-102323.

The qualification report documented that Initially, the controls did not pass [tests] CE102,

RE102, or [International Electrotechnical Commission (IEC) standards] 61000-4-4, 61000-4-

12, and 61000-4-2 tests. Troubleshooting was performed by AMS as requested by ESI and

mitigations were applied to the controls to pass testing. Specifically, capacitors, ferrite beads,

line filters, and snubbers were installed to reduce the as found measured emissions to

acceptable levels (i.e., within the EPRI equipment emissions limits) and qualify the

configuration for EMI. The team conducted walkdowns of the EDG control cabinets and

identified several of the components needed for electromagnetic interference and radio

frequency interference (EMI/RFI) mitigation were not installed. The team also reviewed

DOEJ-VDSNC953976-J001 Electromagnetic Compatibility Evaluation for Plant Use of

Woodward 2301A Speed Control System which provided justification for the removal of

several EMI mitigation devices, including capacitors, that were added to the governor during

the qualification test to meet the EPRI TR-102323 equipment emission limits. SN9604,

Section 4.1.3, Review and Acceptance or an Existing Test Report states that "differences

that are not conservative may require additional testing. All new testing specified should

conform to the requirements of this specification (SN9604). However, an evaluation of

differences may be acceptable as long as it can be shown that an adequate electromagnetic

compatibility (EMC) margin exists.

The licensee determined that the removal of the capacitors was acceptable because the as

found radiated emissions were still below the plant composite limit even though the EPRI

TR-102323 limits were exceeded. The licensee anticipated that the location of the governor

panel and its construction would provide shielding. However, the licensee has not

demonstrated this through testing, nor do they have an evaluation that has quantified the

impact to the overall plant emissions level after installation. EPRI TR-102323 states that the

equipment emissions testing limits must be sufficiently below the highest composite plant

emissions levels to ensure that installation of new equipment does not result in an increase of

the overall plant emissions levels. Additionally, it stated that the equipment susceptibility

testing levels bound the highest composite plant emissions levels and that the margin

between the equipment susceptibility testing levels and the highest composite plant

emissions must be adequate to address uncertainties. The licensees evaluation did not verify

that installation of EDG governor components in a configuration different from the EMI

qualification test did not increase the overall plant emissions level to demonstrate adequate

EMC margin and provide reasonable assurance of electromagnetic compatibility (EMC.) The

inspectors concluded that because these components were removed, the site exposed the

EDGs to intermittent EMI influences as seen during testing, which affected EDG reliability.

8

Corrective Actions: The licensee entered the violation into the licensee's corrective action

program as CR 11176666.

Corrective Action References: CR 11176666

Performance Assessment:

Performance Deficiency: The failure to verify that modifications to the qualified configuration

of the EDG governor would continue to assure acceptable performance when exposed to EMI

was a performance deficiency.

Screening: The inspectors determined the performance deficiency was more than minor

because it was associated with the Design Control attribute of the Mitigating Systems

cornerstone and adversely affected the cornerstone objective to ensure the availability,

reliability, and capability of systems that respond to initiating events to prevent undesirable

consequences. Specifically, the failure to install the EDG governor components in the

qualified configuration exposed the EDGs to failures due to electromagnetic interferences and

affected EDG 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 screened to be of very low safety significance (i.e., Green) because the finding is a

deficiency affecting the design or qualification of a mitigating SSC and the SSC maintained its

operability or PRA functionality.

Cross-Cutting Aspect: H.6 - Design Margins: The organization operates and maintains

equipment within design margins. Margins are carefully guarded and changed only through a

systematic and rigorous process. Special attention is placed on maintaining fission product

barriers, defense-in-depth, and safety related equipment. The licensee failed to install the

EDG governor components in a configuration that maintained the design margins of the EMI

qualification and exposed the EDG to failures due to electromagnetic interferences.

Enforcement:

Violation: 10 CFR 50 Appendix B, to 10 CFR Part 50, Criterion III, Design Control, requires,

in part, that design control measures shall provide for verifying or checking the adequacy of

design, such as by the performance of design reviews, using alternate or simplified

calculational methods, or by the performance of a suitable testing program.

USAR Section 8.1.4.3 Design Criteria, Regulatory Guides, and IEEE Standards, establishes

that the design of the offsite power and onsite Class 1E electric systems conforms with IEEE 323-1974, Qualifying Class 1E Equipment for Nuclear Power Generating Stations.

IEEE 323-1974, Qualifying Class 1E Equipment for Nuclear Power Generating Stations

specified that qualification must demonstrate the acceptable performance of Class 1E

components; to the range of voltage, frequency, load, electromagnetic interference, and

other electrical characteristics.

Licensee Procedure SN9604 SNC - Standard Specification Electromagnetic Interference

(EMI) Qualification Requirements for Southern Nuclear Power Plant Equipment, Section

4.1.3, states in part that "differences that are not conservative may require additional testing.

All new testing specified should conform to the requirements of this specification (SN9604).

9

However, an evaluation of differences may be acceptable as long as it can be shown that an

adequate EMC margin exists.

Contrary to the above, since March 2023, the licensees design control measures failed to

verify that the installation of EDG governor components in a configuration different from the

EMI qualification test was acceptable. Specifically, the licensee failed to verify that adequate

EMC margin was maintained, as required by SN9604, after EDG governor components were

installed without mitigating devices used to qualify the EDG governor. This impacted the

EDGs reliability and exposed the EDGs to failures due to electromagnetic interferences.

Enforcement Action: This violation is being treated as a non-cited violation, consistent with

Section 2.3.2 of the Enforcement Policy.

Minor Violation

71152B

Minor Violation: 10 CFR 50 Appendix B, Criterion V, Instructions, Procedures, and

Drawings, states, in part, activities affecting quality shall be accomplished in accordance with

instructions, procedures, or drawings. Licensee procedure, NMP-GM-002-001, Corrective

Action Program Instructions, Attachment 1, states that an equipment reliability checklist is

required for Equipment failure which results in Unplanned Entry into Technical Specification

(TS) Shutdown RAS < 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , regardless of whether a Risk-Informed Completion Time

(RICT) is available or used. Apply this classification even IF the unit operating mode at the

time of condition discovery DOES NOT require operability, and regardless of how the

condition was discovered. Contrary to the above, since December 2023, the licensee failed

to accomplish safety-related procedure NMP-GM-002-001 following equipment failures of the

engineered safety feature (ESF) chillers that resulted in unplanned entries into TS shutdown

RAS < 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months . Inspectors identified four condition reports for failures of the ESF chillers

that the licensee did not perform an equipment reliability checklist.

Screening: The inspectors determined the performance deficiency was minor. Specifically,

the failure to perform the equipment reliability checklist evaluations did not impact the

corrective actions for the ESF chiller failures.

Enforcement: This failure to comply with 10 CFR 50 Appendix B, Criterion V, Instructions,

Procedures, and Drawings, constitutes a minor violation that is not subject to enforcement

action in accordance with the NRCs Enforcement Policy. The licensee entered the issue into

the corrective action program as condition report (CR) 11175615.

EXIT MEETINGS AND DEBRIEFS

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

On May 8, 2025, the inspectors presented the biennial problem identification and

resolution inspection results to Robert Norris and other members of the licensee staff.

On June 18, 2025, the inspectors presented the biennial problem identification and

resolution inspection results to Jamaal Mayweather.

10

DOCUMENTS REVIEWED

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

71152B

Corrective Action

Documents

Condition Reports

(CR)

10984893, 11012191, 11004677, 11020598, 11041870,

11166342, 11131136, 11109611, 11130060, 11131453,

11127703, 10997871, 11107574, 11102441, 10955463,

10914526, 10894283, 10845558, 10834111, 10833225,

10847097, 11056293, 11056920, 11164921, 11134034,

11115752, 11111785, 11060144, 11057711, 11038391,

11007390, 10993768, 10827428, 10997768, 11063005,

11064269, 11076195, 11062998, 11009968, 11035633,

10984389

71152B

Corrective Action

Documents

Corrective Action

Reports (CAR)

289796, 740078, 322420, 680433, 643431, 280456

71152B

Drawings

1X3D-BH-G03R-2

Elementary Diagram EDG Control Sheet 2

Version 9

71152B

Drawings

1X4AK01 -00445