January 14, 2021

Mr. Chuck Kharrl Site Vice President Southern Nuclear Operating Co., Inc. 7388 North State Highway 95 Columbia, AL 36319 SUBJECT: JOSEPH M. FARLEY NUCLEAR PLANT – DESIGN BASIS ASSURANCE

INSPECTION (PROGRAMS) INSPECTION REPORT 05000348/2020010 AND 05000364/2020010

Dear Mr. Kharrl: On December 9, 2020, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Joseph M. Farley Nuclear Plant and discussed the results of this inspection with Delson Erb 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, /RA/ James B. Baptist, Chief Engineering Br 1 Division of Reactor Safety

Docket Nos. 05000348 and 05000364 License Nos. NPF-2 and NPF-8 Enclosure: As stated cc w/ encl: Distribution via LISTSERV

C. KHARRL 2

SUBJECT: JOSEPH M. FARLEY NUCLEAR PLANT – DESIGN BASIS ASSURANCE INSPECTION (PROGRAMS) INSPECTION REPORT 05000348/2020010 AND 05000364/2020010 dated January 14, 2021

DISTRIBUTION: P. Braxton, RII M. Donithan, RII P. Niebaum, RII R. Patterson, RII S. Sandal, RII M. Schwieg, RII M. Yeminy, contractor S. Kobylarz, contractor RIDSNRRPMFARLEY RIDSNRRDRO RESOURCE PUBLIC ADAMS ACCESSION NUMBER: ML 21015A000 X SUNSI

Review

X Non-Sensitive

Sensitive

X Publicly Available

Non-Publicly Available

OFFICE RII/DRS RII/DRS RII/DRS RII/DRS RII/DRS RII/DRS

NAME M. Schwieg R. Patterson P. Niebaum P. Braxton M. Donithan J. Baptist

DATE 01/14/2021 01/13/2021 01/08/2021 01/07/2021 01/07/2021 01/14/2021

OFFICIAL RECORD COPY

Enclosure

U.S. NUCLEAR REGULATORY COMMISSION Inspection Report

Docket Numbers: 05000348 and 05000364 License Numbers: NPF-2 and NPF-8 Report Numbers: 05000348/2020010 and 05000364/2020010 Enterprise Identifier: I-2020-010-0039 Licensee: Southern Nuclear Operating Co., Inc. Facility: Joseph M. Farley Nuclear Plant Location: Columbia, AL Inspection Dates: April 06, 2020 to December 09, 2020 Inspectors: P. Braxton, Reactor Inspector M. Donithan, Operations Engineer P. Niebaum, Senior Project Engineer R. Patterson, Senior Reactor Inspector S. Sandal, Senior Reactor Analyst M. Schwieg, Reactor Inspector M. Yeminy, contractor S. Kobylarz, contractor Approved By: James B. Baptist, Chief

Engineering Br 1 Division of Reactor Safety

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SUMMARY The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensee’s performance by conducting a design basis assurance inspection (programs) inspection at Joseph M. Farley Nuclear Plant, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRC’s 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.

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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. Starting on March 20, 2020, in response to the National Emergency declared by the President of the United States on the public health risks of the coronavirus (COVID-19), inspectors were directed to begin telework. In addition, regional baseline inspections were evaluated to determine if all or portion of the objectives and requirements stated in the IP could be performed remotely. If the inspections could be performed remotely, they were conducted per the applicable IP. In some cases, portions of an IP were completed remotely and on site. The inspections documented below met the objectives and requirements for completion of the IP REACTOR SAFETY 71111.21M - Design Bases Assurance Inspection (Teams) The inspectors evaluated the following components and listed applicable attributes, permanent modifications, and operating experience: Design Review - Risk-Significant/Low Design Margin Components (IP Section 02.02) (6 Samples)

• Material condition and installed configuration (e.g., visual inspection/walkdown) • Normal, abnormal, and emergency operating procedures • Consistency among design and licensing bases and other documents/procedures • Maintenance effectiveness and records, and corrective action history • Design calculations • Surveillance testing and recent test results • System and component level performance monitoring • Consistency among design and licensing bases and other documents/procedures • System and component level performance monitoring • Diaphragm installation and maintenance

(1) Unit 1 and Unit 2 Auxiliary Feed Water System including the Turbine Driven Auxiliary

Feed Water (TDAFW) Pump and AFW check valves (N23V002A/B and N23V002D/F/H)

(2) Startup Auxiliary Transformers 1A, 1B, 2A, and 2B (3) 1K/1L Feeder breakers (DF02/DG02) (4) Unit 1 and Unit 2 Condensate Storage Tanks

(5) Emergency Diesel Generator (EDG) 1C room ventilation

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(6) EDG Fuel Oil Transfer Pumps

Design Review - Large Early Release Frequency (LERFs) (IP Section 02.02) (1 Sample)

(1) Unit 1 and Unit 2 Reactor Coolant Pump (RCP) Shut Down Seals

• Normal, abnormal and emergency operating procedures • Maintenance effectiveness; Maintenance Rule functions and performance

criteria, procedures for preventive maintenance, inspection, and seal replacement to compare maintenance practices against industry and vendor guidance.

• Component health reports, corrective maintenance records, and corrective action history

• Failure mode analysis of RCP shutdown seal components

Modification Review - Permanent Mods (IP Section 02.03) (4 Samples)

(1) DG02 Breaker Hand Switch Q2R15HS2007BA Replacement (2) SNC929182, 4kV Switchgear Bus 1K Lightning Arrestor Power Cable - 1VADF02Q (3) SNC808954, Unit 1 Train A 4.16 kV Breaker Replacement (4) SNC875753, CRACS Motor Controller Replacement for 2A, 2B, and 3A

Review of Operating Experience Issues (IP Section 02.06) (1 Sample)

(1) IN-18-04, Operating Experience Regarding Failure of Operators to Trip the Plant

When Experiencing Unstable Conditions.

INSPECTION RESULTS Very Low Safety Significance Issue Resolution Process: Capability of Emergency Diesel Building (EDB) Ventilation System to Withstand the Effects of a Tornado

71111.21M

This issue is a current licensing basis question and inspection effort is being discontinued in accordance with the Very Low Safety Significance Issue Resolution (VLSSIR) process. No further evaluation is required. Description: The DBAI inspectors identified an issue of concern in that the EDGs ventilation systems were not specifically shown to be designed to withstand the effects of a tornado depressurization. A tornado pressure drop could potentially damage all EDB exhaust fans and cause failure of all the FNP EDGs ability to maintain its safety functions due to rapidly increasing room temperatures. There are two EDB ventilation subsystems: generator room and switchgear room. The generator room ventilation system maintains a maximum temperature 122F during the generator operation cycle. The switchgear room ventilation system maintains a maximum temperature of 104F. The generator rooms ventilation systems consist of one small power roof exhaust ventilator

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and two large power roof exhaust ventilator in each room (each 100 percent capable units), one motor-operated wall air intake louver in each room for supplying air to the exhaust ventilators, and annunciation equipment for alarming the control room in the event of excessively high or low temperatures within the rooms. The switchgear rooms ventilation systems include in each room a power roof exhaust ventilator, a nonpowered roof exhaust ventilator, and a power roof intake ventilator with connecting ductwork and redundant motor-operated dampers. Both the power intake and power exhaust ventilators are sized to individually provide 100 percent of the heat removal requirements and are totally redundant, and annunciation equipment for alarming the control room in the event of excessively high or low temperatures in the rooms. In April 2017, the licensee performed a safety system functional assessment on the EDGs, it was identified that the motor-operated wall air intake louver in each EDG room did not specifically account for the expected differential pressure for a design basis tornado. The design basis tornado as defined in the site USFAR has a maximum wind speed of 300 mph and a pressure drop of 3.0 psi over a 3.0 sec period. Procedure FNP-0-AOP-21.0 “Severe Weather” was revised to require placing one roof ventilation fan in each EDG room in service to ensure the wall air intake louvers were in the open position to facilitate equalization of the differential pressure. This action would occur if a tornado watch was issued for the site. During the DBAI inspection, the inspectors questioned the technical bases for the procedural change to ensure that the actions incorporated into procedures FNP-0-AOP-21.0 and FNP-0-SOP-43.0 were appropriate. The site provided an information-only calculation to show that the actions incorporated into the procedure were sufficient enough to prevent damage to the exhaust ventilators and louvers in the EDG room but it did not account for the impacts on the switchgear rooms. The inspectors reviewed this calculation and identified the square footage input for the corridor entry ways was less due to the security door and corridor grating. When the inspectors independently evaluated the calculation using the reduced corridor area, the EDG room and switchgear room exhaust ventilators could potentially be damaged during a design basis tornado event. The licensee provided another calculation using Regulatory Guide 1.76 (issued in March 2007) which revised the design-based tornado characteristics based on geographical regions. Plant Farley is in Region I so the revised characteristics were wind speed of 230 mph and 1.2 pressure drop over 2.4 seconds. The licensee determined the EDG roof ventilators would not be damaged with the revised tornado characteristics. However, the inspectors determined the switchgear room roof ventilators could be damaged. The inspectors reviewed the operator action to start one EDG room ventilator after a tornado watch is issued. This action will open the EDG room air intake louvers. If the operator failed to complete this action or a tornado watch was not issued, the EDG room louvers would not be opened. This condition would prevent pressure equalization through the corridor and have an impact on the EDG room exhaust ventilators. The inspectors evaluated other tornado characteristics and determined a tornado equivalent to a Region II with a maximum wind speed of 200 mph could damage the EDG room exhaust ventilators if the operator action was not completed. The inspectors reviewed the EDG building calculation (2142-AH-003, Design Generator

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Building Concrete Calculations, 3/11/87) demonstrate that the DG portions of the building are sufficiently ventilated such that the depressurization effects would be negligible. This was demonstrated by meeting criteria in Bechtel design Topical Report BC-TOP-3-A (ML14093A218) which concluded that “no significant pressure differential develops if there is a minimum of 1 FT2 of vent area to 1000 FT3 of room volume.” Calculation 2142-AH-003 utilizes the Hatch Nuclear Plant DG building as the structure and ventilation input which provides a very similar structure and ventilation equipment layouts as the Farley design. The Hatch DG building has the same layout feature as Farley where a large corridor with grating air intakes one each end provides protection of each DG room’s ventilation intake dampers and personnel access doors from missiles and wind loading. The calculation determined the DG rooms have adequate ventilation openings suitable to be classified as “fully vented.” However, the DG switchgear rooms were determined to be only “partially vented” and a depressurization computer run was performed. The results of the DG switchgear room depressurization indicate structure would not be in jeopardy. Observation of the structural calculation depressurization results indicates the differential pressure challenge to the ventilation fan and ductwork would be reduced to approximately 0.3 psi. The inspectors questioned the conclusion that no significant pressure differential develops in the EDB rooms. The corridor entry dimensions did not consider the loss of area due to the doors and grating. If the reduce corridor area was used, the fully vented criteria (1 FT2 of vent area to 1000 FT3 of room volume.) would not be met and a further analysis would be required. Farley switchgear room have a different layout from Hatch EDB. Farley has two large switchgear room while Hatch has five smaller switchgear room. The Farley layout would create a larger differential pressure during a tornado de-pressurization and it could impact the switchgear fans. The inspectors could not determine if Farley’s EDB ventilation design was based on this calculation or whether significant differential pressure would develop in the EDB rooms without further analysis. The inspectors evaluated the impact of the loss of the switchgear room roof ventilators and determined the condition was recoverable. Since the switchgear generates less heat, it would take several hours before a high temperature room alarm would occur. The operators would have enough time to take compensatory actions by installing temporary room fans. The inspectors evaluated the impact of loss of the EDG room roof ventilators and determine the condition was unrecoverable. If the EDG roof exhaust ventilators were damaged, a running EDG could overheat within an hour. Given the size of these ventilator fans (56,200 CFM), the operators could not install temporary fans to remove the running EDG room heat. This could result in a complete loss all onsite emergency power Following the inspector’s identification of the concern, the licensee entered the issue into their corrective action program as nuclear condition report NCR 10704499, and took additional actions to inspect the fans and dampers following a tornado event. Licensing Basis: The NRC staff reviewed both current and historical regulatory requirements and regulatory correspondence related to the EDB tornado protection criterion. The main documents reviewed are detailed below. · USFAR sections 3.2.1, 3.3.2 and Table 3.2-1

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· 10 CFR 50, Appendix A, Criterion 2—Design bases for protection against natural phenomena. · 10 CFR 50, Appendix B, Criterion III, “Design Control,” · Regulatory Issue Summary (RIS) 2006-23 · Regulatory Issue Summary (RIS) 2015-06 · Regulatory Guide 1.76 (issued in March 2007) The inspectors were not able to conclude whether the issue of concern was part of the plant’s current licensing basis. As a result, the effort to determine whether the EDG ventilation systems should be protected from the effects of a tornado depressurization is judged to likely require a significant amount of resources to develop a conclusion that far outweighed the issue’s potential safety significance. As a result, the issue could be closed without immediate enforcement action and treated under the very low safety significance issue resolution process. Significance: A risk evaluation was performed by a regional senior reactor analyst using SAPHIRE Version 8.2.2 and NRC Farley SPAR model Version 8.57. The conditional analysis assumed failure of the EDG ventilation fans for tornado initiating events with wind speeds greater than 200 miles per hour with a one-year exposure time. The dominant sequences were a tornado initiator accompanied by a loss of offsite power with failures of the emergency diesel generators, the turbine driven AFW pump, and operator actions to recover offsite power. The analysis determined that if a performance deficiency was assumed to have existed, it would have resulted in an increase in core damage frequency of <1E-6/year, representing very low safety significance (Green). Technical Assistance Request: A technical assistance request (TAR) was not initiated. Corrective Action Reference: NCR 10704499

EXIT MEETINGS AND DEBRIEFS The inspectors verified no proprietary information was retained or documented in this report.

• On December 9, 2020, the inspectors presented the design basis assurance inspection (programs) inspection results to Delson Erb and other members of the licensee staff.

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DOCUMENTS REVIEWED Inspection Procedure

Type Designation Description or Title Revision or Date

71111.21M Calculations Revised tornado depressurization model 38.04 Unit 2 Verification of AFW Flow Bases 4 40.02 Unit 1 Verification of AFW Flow Bases 4 E-035.02.A Setting of Protective Relays for 4.16kV Auxiliary Power

System Rev.8

Calibration Records

FNP-BFM-007 Data Sheet 7, Maintenance Test Gauge and Flowmeter Calibration in Support of Units 1 and 2 STP-158

4.0

Corrective Action Documents

10364209 Time Critical Operator Actions periodic validation results from training segment 17-3

05/11/2017

10540234, 10547916, 731598, 753172, 807775, 10487968, 10495824, 10601538, 1057275, 10616812, 10660702, 10656967, 10475772, 10601078

10698360 Tracking and trending of Time Critical Operator Action Program periodic validation

03/25/2020

CARs 276841, 273775 Corrective Action Documents Resulting from Inspection

10703532 ***This is a place holder fro Stan's procedure discrepancies

TBD

CR 10703089 DBAI NRC identified - NMP-OS0014-001 TCOA E04 (Response to Security Event)

04/21/2020

CR 10703095 DBAI NRC identified - NMP-OS0014-001 TCOA E16 04/21/2020 CR10704499 NRC identified FNP-0-SOP-43.0 04/22/2020 CR10732049 NRC minor violation - transformer loading 8/21/2020 CR10732057 NRC Minor Violation - Testing Rig Accuracy 08/21/2020 CRs 10706041, 10700974

Drawings C-172765 Elementary Diagram – 4160 V Bus 1K Feeder Breaker to Station Service Transformer 1K

Rev. 7

D-172747 Elementary Diagram – Service Water Pump No. 1A – Rev.12

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Inspection Procedure

Type Designation Description or Title Revision or Date

Bus 1K D-172748 Elementary Diagram – Service Water Pump No. 1B –

Bus 1K Rev. 13

D-172749 Elementary Diagram – Service Water Pump No. 1C – Bus 1K

Rev. 14

D-172948 Wiring Diagram – 4160 Volt Switchgear Bus 1K Cell No. DK01, Sheet. 1

Rev. 7

D-173013 Outdoor AC Distribution Cabinet (Low Voltage Switchgear)

Rev. 5

D-175007 Unit 1 Auxiliary Feedwater System Piping and Instrumentation Diagram (PI&D)

38

D-175033 Unit 1 P&ID - Main Steam and Auxiliary Steam Systems

28

D-177001 Single Line Electrical Auxiliary System (Emergency 4160 & 600 V), Sheet. 1

Rev. 23

Engineering Changes

SNC1012405 Breaker DG02 Remote Handswitch Replacement — Q2R15HS2007BA

Rev. 2

SNC808954 Unit 1 Train A 4.16 kV Breaker Replacement Rev. 4.0 SNC929182 4kV Switchgear Bus 1K Lightning Arrestor Power

Cable-1VADF02Q

Rev. 2.0

Engineering Evaluations

Eval 5.29.96 AFW System Check Valve Reversal Flow Operability Test and Check Valves

May 29, 1996

TEs 1024644, 732042, 808790, 318646

Westinghouse LTR-CRA-16-102

Steam Generator Tube Rupture Margin to Overfill Analysis Report

1

Miscellaneous CCSI As- Found Inspection Report for Unit 2 Condensate Storage Tank Diaphragm

11/24/2020

A181001 Functional System Description - Service Water System 69.0 A181004 Functional System Description Electrical Distribution

System Rev. 58

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Inspection Procedure

Type Designation Description or Title Revision or Date

A181010 Functional System Description Auxiliary Feedwater System

38

FNP-0-M-115 Check Valve Condition Monitoring Plan 8 IER LI-17-5 Farley's response to IER LI-17-5, Line of Sight to the

Reactor Core 3

Job Performance Measure SO-449F

Operation of Steam Generator Atmospheric Relief Valves for TCOA of EEP-3.0 with a Loss of Instrument Air

02/08/2018

MIS-17-031 Unit 1 Fifth 10-Year Interval Valve Inservice Testing Basis Document

1

MIS-17-032 Unit 2 Fifth 10-Year Interval Valve Inservice Testing Basis Document

1

PMCR 97345 Change frequency of CST Inspection to 3 years 7/23/2020 PMCR95348 Preventive Maintenance Change Request for AFW

check valves April 7, 2020

RER 03-032 Evaluation and Testing of K& N Handswitches 12/2/03 SNC1012405 Breaker DG02 Remote Handswitch Replacement —

Q2R15HS2007BA Rev. 2

U-419253 Qualification Report on CA10 Series Selector Switches and Aluminum Handles and Retaining Nuts

Rev. 4

U-734326 Installation, Operation and Maintenance Manual for Kraus & Naimer Hybrid Contact Selector Switches

Rev.1

U262093 Auxiliary Feedwater Pump Turbine Drive Manual 14 U612339 Unit 2 - Use of Westinghouse Shield Passive Shutdown

Seal for Flex Strategies 1

U737296 Farley – Unit No. 1&2 Qualification Report QR 17-02 for Siemens Medium Voltage Vacuum Replacement Circuit Breakers, 5 KV MSV and Accessories

Rev. 2.0

U737307 Siemens 4160 V Circuit Breaker MSV - Safety-Related Schematic & Wiring Diagram 18-806-541-411

Rev. 1

Procedures F-LT-SG-TCOA Licensed Operator Continuing Training Simulator 3.2

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Inspection Procedure

Type Designation Description or Title Revision or Date

Exercise Guide FNP-0-ARP-8.0 Annunciator Response Procedure - Service Water

Structure 27.0

FNP-0-MP-10 Reactor Coolant Pump Uncoupling/Recoupling 2 FNP-0-MP-9.0 RCP Seal Examination and Replacement Incorporating

the Shut Down Seal 1

FNP-1-AOP-4.0 Loss of Reactor Coolant Flow 21 FNP-1-AOP-4.1 Abnormal Reactor Coolant Pump Seal Leakage 14 FNP-1-ARP-1.12 Main Control Board Annunciator Panel M Rev. 75 FNP-1-ARP-5.0 Unit Startup Transformer Miscellaneous Alarm Panel Rev 13.1 FNP-1-ECP-3.1 SGTR With Loss of Reactor Coolant, Subcooled

Recovery Desired 25.0

FNP-1-EEP-0 Reactor Trip or Safety Injection 50 FNP-1-EEP-1 Loss of Reactor or Secondary Coolant 34 FNP-1-EEP-3 Steam Generator Tube Rupture 32 FNP-1-EEP-3.0 Steam Generator Tube Rupture 31.0 FNP-1-MP-7.3 Turbine Driven Aux Feed Pump Overspeedtrip Setpoint

Check 7

FNP-1-SOP-24.0 Service Water System 88.0 FNP-1-STP-22.16 Turbine Driven Auxiliary Feedwater Pump Quarterly

Inservice Test 68

FNP-1-STP-22.24 Auxiliary Feedwater System Check Valve Reverse Flow Closure Operability Test

10 through 17

FNP-1-STP-22.30 Auxiliary Feedwater Pump Discharge Check Valve Reverse Flow Closure Operability Test

2, 7 through 12

FNP-2-AOP-4.0 Loss of Reactor Coolant Flow 21 FNP-2-AOP-4.1 Abnormal Reactor Coolant Pump Seal Leakage 8 FNP-2-ECP-0.0 Loss of All AC Power 31 IP-ENG-001 Standard Design Process Rev. 1 NMP-OS-014 Time Critical Operator Action Program 2.0 NMP-OS-014-001 FNP Time Critical Operator Action Program 7.0

Work Orders SNC400246 Performance of FNP-1-STP-22.30 April 20, 2015

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Inspection Procedure

Type Designation Description or Title Revision or Date

SNC416549 Inspect the CST tank bladder for degradation 11/14/2020 SNC528671 Unit 1 TDAFWP - Overspeed Trip Test and Coupling

Lube April 5, 2018

SNC53150, SNC531515, SNC531516, SNC390897, SNC390897, SNC390898, SNC391152, SNC413154, SNC546630, SNC546630, SNC546650, SNC546651, SNC353892, SNC339899, SNC391154, SNC331162, SNC573130, SNC391165, SNC1039631, SNC1039762, SNC1041172, SNC1041310, SNC1042746, SNC1042900, SNC808954, SNC565614, SNC910159,SNC1012725

SNC975145 FNP-1-STP-22.24 Nov. 4, 2019 SNC981614 Performance of FNP-2-STP-22.24 A Train Dec. 17,

2019 SNC992621 FNP-1-STP-22.24 Nov. 6, 2019