IR 05000413/2023004

– Integrated Inspection Report 05000413-2023004 and 05000414-2023004

ML24029A042
Person / Time
Site:	Catawba
Issue date:	02/02/2024
From:	Eric Stamm NRC/RGN-II/DRP/RPB1
To:	Flippin N Duke Energy Carolinas
References
IR 2023004
Download: ML24029A042 (13)

Text

SUBJECT:

CATAWBA NUCLEAR STATION - INTEGRATED INSPECTION REPORT 05000413/2023004 AND 05000414/2023004

Dear Nicole Flippin:

On December 31, 2023, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Catawba Nuclear Station. On January 31, 2024, the NRC inspectors discussed the results of this inspection with you 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, Eric J. Stamm, Chief Reactor Projects Branch 1 Division of Reactor Projects Docket Nos. 05000413 and 05000414 License Nos. NPF-35 and NPF-52

Enclosure:

As stated

Inspection Report

Docket Numbers:

05000413 and 05000414

License Numbers:

NPF-35 and NPF-52

Report Numbers:

05000413/2023004 and 05000414/2023004

Enterprise Identifier:

I-2023-004-0016

Licensee:

Duke Energy Carolinas, LLC

Facility:

Catawba Nuclear Station

Location:

York, South Carolina

Inspection Dates:

October 1, 2023, to December 31, 2023

Inspectors:

D. Rivard, Senior Resident Inspector

A. Wang, Resident Inspector

M. Bradfield, Reactor Technology Instructor

S. Egli, Senior Construction Inspector

J. Hickey, Senior Project Engineer

A. Hutto, Senior Project Engineer

J. Viera, Senior Operations Engineer

Approved By:

Eric J. Stamm, Chief

Reactor Projects Branch 1

Division of Reactor Projects

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Catawba Nuclear Station, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.

List of Findings and Violations

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

Additional Tracking Items

None.

PLANT STATUS

Unit 1 operated at or near 100 percent rated thermal power (RTP) for the entire 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.

71111.01 - Adverse Weather Protection

Seasonal Extreme Weather Sample (IP Section 03.01) (1 Sample)

(1) The inspectors evaluated readiness for seasonal extreme weather conditions prior to the onset of seasonal cold temperatures for the following systems:

Plant heating water system Refueling water storage tank heat trace controllers

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

(1) The inspectors evaluated the adequacy of the overall preparations to protect risk-significant systems from impending drought impact on December 18, 2023.

71111.04 - Equipment Alignment

Partial Walkdown Sample (IP Section 03.01) (6 Samples)

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

(1)2A containment spray pump alignment during maintenance on the 2B containment spray pump motor on October 18, 2023

(2) Nuclear service system during system alignment for intake and discharge to the nuclear service water pond on November 14, 2023 (3)1A emergency diesel generator standby alignment on November 14, 2023

(4) Unit 1 vital DC battery system alignment on November 21, 2023

(5) Unit 1A low pressure injection pump during maintenance on the 1B low pressure injection pump on November 30, 2023 (6)2A and B intermediate pressure emergency core cooling system pump valve alignment of accessible valves in the auxiliary building on December 11, 2023

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 Area 8: Unit 1 electrical penetration room 372, elevation 560, on October 11, 2023

(2) Fire Area 7: Unit 2 electrical penetration room 362, elevation 560, on October 11, 2023

(3) Fire Area 1: Units 1 and 2 auxiliary building, elevation 522, residual heat removal pump and containment spray pump areas, on October 18, 2023

(4) Fire Area 27: Unit 2 diesel generators 2A room, on November 17, 2023

(5) Fire Area 28: Unit 2 diesel generators 2B room, on November 17, 2023

(6) Fire Area 12: Unit 2 auxiliary building, elevation 577, electrical penetration room (room 484), on November 22, 2023

(7) Fire Area 13: Unit 1 auxiliary building, elevation 577, electrical penetration room (room 494), on November 22, 2023

Fire Brigade Drill Performance Sample (IP Section 03.02) (1 Sample)

(1) The inspectors evaluated the onsite fire brigade training and performance during announced Drill 2023-042: Unit 1 spent fuel building ventilation filter A2 on October 19, 2023.

71111.06 - Flood Protection Measures

Flooding Sample (IP Section 03.01) (1 Sample)

(1) The inspectors evaluated internal flooding mitigation protections for the turbine building, 568' elevation.

71111.07A - Heat Exchanger/Sink Performance

Annual Review (IP Section 03.01) (1 Sample)

The inspectors evaluated readiness and performance of:

(1) PT/2/A/4400/06B, "Containment Spray Heat Exchanger Capacity Test," performed on October 18, 2023

71111.11A - Licensed Operator Requalification Program and Licensed Operator Performance

Requalification Examination Results (IP Section 03.03) (1 Sample)

The licensee completed the annual requalification operating examinations required to be administered to all licensed operators in accordance with Title 10 of the Code of Federal Regulations 55.59(a)(2), "Requalification Requirements," of the NRC's "Operator's Licenses." The inspector performed an in-office review of the overall pass/fail results of the individual operating examinations, and the crew simulator operating examinations in accordance with IP 71111.11, "Licensed Operator Requalification Program and Licensed Operator Performance." These results were compared to the thresholds established in Section 3.03, "Requalification Examination Results," of IP 71111.11.

(1) The inspectors reviewed and evaluated the licensed operator examination failure rates for the requalification annual operating exam administered on November 30, 2023.

71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance

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

(1) The inspectors observed and evaluated two operating crews responding to a main feedwater pump trip from 100 percent power and associated turbine runback followed by a loss of letdown flow and recovery, a loss of the A vital electrical bus, loss of off-site power, manual safety injection, and termination of safety injection, on November 2, 2023.

71111.12 - Maintenance Effectiveness

Maintenance Effectiveness (IP Section 03.01) (2 Samples)

The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components (SSCs) remain capable of performing their intended function:

(1) Action request (AR) 02472448, Catawba 10CFR50.65(a)(3) maintenance rule assessment

(2) Nuclear condition report (NCR) 02487301, 1B diesel generator field flash failure

Quality Control (IP Section 03.02) (1 Sample)

The inspectors evaluated the effectiveness of maintenance and quality control activities to ensure the following SSCs remain capable of performing their intended function:

(1) NCR 02480119, 02480403, and 02482422 incorrect grease used in motor operated valves associated with safety related systems including the residual heat removal, service water, and safety injection systems

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management Sample (IP Section 03.01) (5 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) Protected equipment measures during 2B containment spray pump motor offline testing, on October 18, 2023

(2) Protected equipment measures during 2B centrifugal charging pump motor relay testing, on November 16, 2023

(3) Protected equipment measures during 1B low pressure injection pump motor offline testing and system maintenance, on November 30, 2023

(4) Protected equipment measures during 1A component cooling train inoperable but available with 1A decay heat removal train inoperable, on December 11, 2023

(5) Compensatory actions and protected equipment measures inspected following acceptance criteria failure of 1B diesel generator (DG) during PT/1/A/4350/015 A, Diesel Generator 1A Periodic Test on December 12, 2023; walkdown conducted on December 13, 2023

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment (IP Section 03.01) (10 Samples)

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

(1) NCR 02473071, 1NC-033A close structural limit exceeded on as found test

(2) NCR 02473418, lube oil leakage downstream of 1A emergency diesel generator (EDG) lube oil strainer 1A1 check valve, on October 10, 2023

(3) NCR 02487301, 2B EDG failure to flash field

(4) NCR 02488447, operability of Unit 2 turbine driven auxiliary feedwater pump while auxiliary steam supply to turbine driven auxiliary feedwater pump heat trace panel alarm function to the control room was not functioning

(5) NCR 02489192, spent fuel area ventilation fire dampers 2VF-FD013 and 2VF-FD013 did not meet the inspection procedure acceptance criteria

(6) NCR 02492912, evaluation of Unit 2 component cooling (KC) system upon discovery of frozen snubber

(7) NCR 02493819, 2B EDG shutdown monitoring panel loss of display

(8) NCR 02496710, resolve 1B inadequate core cooling monitor subcooling Indication, on December 4, 2023

(9) NCR 02496998, steam generator level transmitter 1CFLT5570 drifted high out of spec, on December 6, 2023

(10) NCR 02497721, 1A EDG did not maintain adequate voltage following hot restart during a periodic test performance in accordance with PT/1/A/4350/015 A, on December 12, 2023

71111.18 - Plant Modifications

Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02) (4 Samples)

The inspectors evaluated the following temporary or permanent modifications:

(1) Engineering change (EC) 406881, replacement on Unit 1 refueling water storage tank level transmitters, on October 9, 2023

(2) EC 411366, conventional waste water (WC) pond piping replacement (turbine building flood impact), on October 25, 2023

(3) EC 423409, revise auxiliary feedwater pump flow test acceptance criteria, on November 24, 2013

(4) EC 107798, revise design documents to reflect Lisega snubbers as acceptable substitutes for AD-70R snubbers, on November 27, 2023

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) (12 Samples)

(1) PT/1/B/4250/002 A, "Main Turbine Trip Test," following repairs made under work request 20256520 for failure of electrical trip test, on October 8, 2023

(2) PT/2/A/4200/013 C, "RN Valve Inservice Test," for valves 2RN030A, 2RN049A, 2RN051A, 2RN144A, and 2RN148A, on October 10, 2023

(3) Work order (WO) 20628839, repair loose mounting plate for position sensor on 1 ISV 1 main turbine integrated intercept valve, on October 10, 2023

(4) PT/2/A/4200/04C, "Containment Spray Pump 2B Performance Test," on October 18, 2023

(5) OP/1/A/6250/002, "Auxiliary Feedwater System," following governor oil level adjustment on WO 20618438, on October 31, 2023

(6) NCR 02492912, 2-R-KC-0276 component cooling water snubber failed freedom of motion test, on November 2, 2023

(7) OP/2/A/6250/002, "Auxiliary Feedwater System," following breaker swap on WO

===20564907, on November 9, 2023

(8) WO 20589033, functional test after oil replacement to the Unit 2 2B coolant charging pump, on November 16, 2023

(9) WO 20595352, 1B decay heat removal pump miniflow control pressure switch replacement, on November 30, 2023

(10) PT/1/A/4200/013 E, Enclosure 13.11, AFW 1CA-52 Valve Inservice Test, following solenoid valve replacement on WO 20570626, on December 5, 2023

(11) PT/1/A/4200/013 E, Enclosure 13.17, AFW 1CA-64 Valve Inservice Test, following solenoid valve replacement on WO 20570627, on December 5, 2023

(12) PT/1/A/4350/002 A, "Diesel Generator 1A Operability Test," and PT/1/A/4350/015 A, "Diesel Generator 1A Periodic Test," following failure to attain voltage requirement and replacement of voltage regulator and voltage reference unit, NCR 02497721, on December 20, 2023 Surveillance Testing (IP Section 03.01)===

(1) PT/0/A/4200/083, "RN (nuclear service water) Pond Swap Logic Test," on October 1, 2023

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

(1) PT/2/A/4200/029, "SA Valve Inservice Test (QU)," and PT/2/A/42000/009 A, "Auxiliary Safeguards Test Cabinet Periodic Test," for steam supply to Unit 2 turbine driven auxiliary feedwater pump, on October 15, 2023

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

(1) WO 20596752, perform FLEX equipment preventive maintenance

71114.06 - Drill Evaluation

Select Emergency Preparedness Drills and/or Training for Observation (IP Section 03.01) (1 Sample)

(1) Emergency response organization drill CNS 23-05 and critique that included a loss of coolant accident with containment boundary breach due to a series of earthquakes and aftershocks, resulting in a final declaration of site area emergency, on December 6, 2023.

Drill/Training Evolution Observation (IP Section 03.02) (1 Sample)

The inspectors evaluated:

(1) License operator requalification annual simulator examination ASE-2311 on October 26, 2023. The training evolution involved a loss of an essential electrical bus followed by a loss of all electrical power (station blackout).

OTHER ACTIVITIES - BASELINE

===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:

IE01: Unplanned Scrams per 7000 Critical Hours Sample (IP Section 02.01)===

(1) Unit 1 (October 1, 2022, through September 30, 2023)

(2) Unit 2 (October 1, 2022, through September 30, 2023)

MS05: Safety System Functional Failures (SSFFs) Sample (IP Section 02.04) (2 Samples)

(1) Unit 1 (October 1, 2022, through September 30, 2023)

(2) Unit 2 (October 1, 2022, through September 30, 2023)

BI01: Reactor Coolant System (RCS) Specific Activity Sample (IP Section 02.10) (2 Samples)

(1) Unit 1 (October 1, 2022, through September 30, 2023)

(2) Unit 2 (October 1, 2022, through September 30, 2023)

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

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

(1) NCR 02458114, 02466829, nuclear service water cable manhole water detection and removal

(2) NCR 02468311, Unit 2 2A1 component cooling water pump discharge check valve failure

(3) NCR 02490146, 02459924, auxiliary power system 6900/4160vac transformer high core temperatures

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

(1) The inspectors reviewed the licensees corrective action program and maintenance rule assessment for potential adverse trends in the standby shutdown facility diesel equipment performance that might be indicative of a more significant safety issue. No negative trends that could lead to a safety issue were identified.

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

(1) The inspectors evaluated NCR 02483565, inadvertent steam generator power operated relief valve operation and licensees response on October 19,

INSPECTION RESULTS

No findings were identified.

EXIT MEETINGS AND DEBRIEFS

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

• On January 31, 2024, the inspectors presented the integrated inspection results to Nicole Flippin and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

71111.01

Procedures

PT/0/B/4700/038

Cold Weather Protection

Drawings

CN-2562 Series

OP/1/A/6200/004

Residual Heat Removal System

156

OP/2/A/6200/006

Safety Injection System

71111.04

Procedures

OP/2/A/6200/007

Containment Spray System

061

71111.06

Calculations

CN-1109.04-00-

0006

Service Building Foundation Mat

71111.07A

Procedures

PT/2/A/4400/006

B

NS Heat Exchanger 2B Heat Capacity Test

2

Corrective Action

Documents

2492270,

2496710

Miscellaneous

EC 423223, 404212

71111.12

Work Orders

WRs 20258474, 20257930, 20260082

WOs 20631817, 20638326, 20633069

Corrective Action

Documents

2497721

Corrective Action

Documents

Resulting from

Inspection

2497918

Protected Equipment Clearance: PRT-2-23-2B NS OOS-

204

Protected Equipment Clearance: PRT-1-23-1B ND OOS-

235

Miscellaneous

Protected Equipment Clearance: PRT-1-23-1A DG INOP -

253(1)

PT/1/A/4350/002

C

Available Power Source Operability Check

27

Procedures

PT/1/A/4350/015

A

Diesel Generator 1A Periodic Test

056

71111.13

Work Orders

20639048, 20639361, 20639995

Corrective Action

Documents

2492911, 02492912, 02493211, 02393255, 02496710,

2496998, 02497721

Impairment ID CNS-23-008484

Miscellaneous

CNS 2B EDG Relays 2DECPB/R7 and 2ELCP0329/GB

Metallurgy File: #6394

Procedures

AD-OP-ALL-0105

Operability Determinations

71111.15

Work Orders

20632304, 20582370, 20505990-01, 20207097, 20216667,

258292, 20258298, 20260082, 20636990, 20260189,

20639048, 20639361

Corrective Action

Documents

2493211, 02480119, 02480403, 02482422

Drawings

CN-1684-

00.MAT-10-01

Substitution Charts for Grinnel Components

Engineering

Changes (ECs)

404212, 423223

MP/0/A/7650/053

Installation of Concrete Anchors

053

MP/0/A/7650/059

Controlling Procedure for Support/Restraint Maintenance

Activities

2

MP/0/A/7650/148

ASME Section XI Repair/Replacement Activities

24

PT/1/A/4200/013

E

CA Valve Inservice Test (QU)

097

Procedures

PT/2/A/4200/004

C

Containment Spray Pump 2B Performance Test

049

71111.24

Work Orders

20596752 (Flex Semi annual PM)

08/31/23

Corrective Action

Documents

2496971, 02497010, 02497200

Procedures

AD-EP-ALL-0100,

AD-EP-ALL-0101,

EP-CNS-EPLAN-

ANNEX, CSD-EP-

CNS-0101-02

71114.06

Work Orders

260180

Corrective Action

Documents

2497222, 02482946, 02452547, 02397351, 02370771

71152A

ECs 23117