Text

– Integrated Inspection Report 05000327/2023003 and 05000328/2023003
	ML23292A080
Person / Time
Site:	Sequoyah
Issue date:	11/03/2023
From:	Louis Mckown; Division Reactor Projects II
To:	Jim Barstow; Tennessee Valley Authority
References
	IR 2023003
	Download: ML23292A080 (1)
	v • d • e

SUBJECT:

SEQUOYAH, UNITS 1 AND 2 - INTEGRATED INSPECTION REPORT 05000327/2023003 AND 05000328/2023003

Dear Jim Barstow:

On September 30, 2023, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Sequoyah, Units 1 and 2. On October 10, 2023, the NRC inspectors discussed the results of this inspection with Mr. Tom Marshall 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, Louis J. McKown, II, Chief Reactor Projects Branch 5 Division of Reactor Projects Docket Nos. 05000327 and 05000328 License Nos. DPR-77 and DPR-79

Enclosure:

As stated

Inspection Report

Docket Numbers:

05000327 and 05000328

License Numbers:

DPR-77 and DPR-79

Report Numbers:

05000327/2023003 and 05000328/2023003

Enterprise Identifier:

I-2023-003-0036

Licensee:

Tennessee Valley Authority

Facility:

Sequoyah, Units 1 and 2

Location:

Soddy Daisy, TN 37379

Inspection Dates:

July 01, 2023, to September 30, 2023

Inspectors:

D. Hardage, Senior Resident Inspector

A. Price, Senior Resident Inspector

S. Ninh, Senior Project Engineer

Approved By:

Louis J. McKown, II, Chief

Reactor Projects Branch 5

Division of Reactor Projects

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Sequoyah, 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 operated at or near rated thermal power (RTP) for the entire inspection period.

Unit 2 operated at or near 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) (3 Samples)

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

(1) Unit 1 emergency core cooling system (ECCS) lineup in the Main Control Room (MCR) during maintenance on centrifugal charging pump (CCP) 1B and Unit 2 ECCS lineup in the MCR following maintenance on CCP 2B on July 26, 2023.

(2) Essential raw cooling water (ERCW) valves servicing Unit 1 Train B safety related equipment during 1A CCP and 1A residual heat removal system (RHR) pump maintenance on August 2, 2023.

(3) Vital Battery V alignment to Battery Board IV during Vital Battery I surveillance testing on August 29, 2023.

71111.05 - Fire Protection

Fire Area Walkdown and Inspection Sample (IP Section 03.01) (5 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) Unit 1 and Unit 2 Auxiliary Building, Elevation 734 and 759 on July 05, 2023

(2) Unit 1 and Unit 2 Auxiliary Building, Elevation 669 on July 16, 2023

(3) Unit 1 and Unit 2 Auxiliary Building, Elevation 714 on August 10, 2023

(4) Unit 1 and Unit 2 Auxiliary Building, Elevation 734 Electrical Board Rooms on August 16, 2023

(5) Unit 1 and Unit 2 Auxiliary Building, Elevation 749 Electrical Board, Battery, &

Transformer Rooms on September 6, 2023

71111.06 - Flood Protection Measures

Flooding Sample (IP Section 03.01) (1 Sample)

(1) The inspectors evaluated external flooding mitigation protections in the ERCW intake pumping station on July 12, 2023

71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance

Licensed Operator Performance in the Actual Plant/Main Control Room (IP Section 03.01) (1 Sample)

(1) The inspector observed and evaluated licensed operator performance in the main control room during unplanned 2A component cooling water pump outage including Rod Pattern Adjustment on July 25-26, 2023.

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

(1) The inspectors observed and evaluated a simulator training scenario including a ruptured steam generator on August 21, 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) Maintenance rule preventable functional failure of K-A ERCW pump due to overcurrent trip (CDE 3184) on July 19, 2023

(2) Maintenance rule functional failure of Unit 2 B Train Emergency Gas Treatment Air Cleanup due to failed damper mechanical interlock linkage (CDE 3210) on August 9, 2023

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) Week of July 17-21, 2023, including protected equipment reviews for scheduled maintenance on 2A motor-driven auxiliary feedwater (MDAFW) pump on July 17, 2023, and during emergent maintenance due to the failure of 1A-A 669 Penetration Room Cooler and on U1 Power Cabinet SCD (Shutdown Banks C and D) due to Rod Control Urgent Failure Alarm with U1 Rod Control in manual on July 19, 2023.

(2) Unit 1 and 2, week of July 30 - August 5, 2023, including protection equipment reviews for scheduled maintenance on the 1A CCP, 1A safety injection pump, and 1A RHR pump.

(3) Unit 1 and 2, week of August 7-11, 2023, including protected equipment reviews for scheduled maintenance on 120V Vital Inverter 0-IV and entry into AOP-N.02 Tornado Watch.

(4) Unit 1 and 2, week of August 27 - September 2, 2023, including protected equipment reviews for dry cask loading operations and scheduled maintenance on vital battery charger I and auxiliary air compressor A.

(5) Week of September 11-15, 2023, including protected equipment reviews for the cutout and replacement of the 1A CCP Discharge Check Valve and review of the associated Risk-Informed Completion Time (RICT) requirements on September 14, 2023.

(6) Week of September 18-22, 2023, including protected equipment reviews for the unplanned 1B emergency diesel generator (EDG) outage and review of the associated RICT requirements on September 27, 2023.

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment (IP Section 03.01) (6 Samples)

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

(1) Potential AFW design vulnerability on July 7, 2023.

(2)1B Charging pump increased balance drum flow on July 28, 2023.

(3)1A1/1A2 component cooling system heat exchangers fouling limit exceeded on August 1, 2023.

(4) U2 Post accident sampling system: Documentation of being outside of current licensing basis on August 11, 2023.

(5) Challenge to operability of the 1A CCP if left in a standby condition for an extended period of time based on the voiding upstream of 1-CHK-62-525 on August 22, 2023.

(6) Site response to emergent failure of 1B EDG, including the common cause failure and extent of condition analysis for EDGs 1A, 2A, 2B on September 29, 2023.

71111.18 - Plant Modifications

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

The inspectors evaluated the following temporary or permanent modifications:

(1) DEC SQN-19-885, 6.9kV ITE Breaker Replacement Equivalency on July 14, 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) (6 Samples)

(1) Work Order (WO) 123852417, Replace failed 2-PX-98-6002, single point vulnerability for steam generator level control on July 13, 2023

(2) WO 123093811, Calibrate CCP 2B-B Aux Oil Pump control switches on July 26, 2023

(3) WO 123630250, Replace safety injection pump 1A-A breaker control device on July 31, 2023

(4) WO 123190039, 2-SI-SXP-074-201.B RHR Pump 2B XI Test on August 23, 2023

(5) WO 1123202367, Perform bridge and megger test of component cooling water pump 1B on September 6, 2024

(6) WO 124018372, EDG 1B 24hr Run following EDG 1B unplanned outage on September 27, 2023.

Surveillance Testing (IP Section 03.01) (3 Samples)

(1)0-SI-OPS-092-078.0, Unit 2 Power Range Neutron Flux Channel Calibration by Heat Balance Comparison, on July 12, 2023

(2) WO 123125058, U1 Calibration of Power Range Nuclear Instrumentation Systems following In/Excore Detector Calibration on August 17, 2023

(3) WO 123125097, EDG 1A 24hr Run and Load Rejection Test on September 13,

OTHER ACTIVITIES - BASELINE

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

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

Main article: IP 71151

(1) Unit 1 (July 1, 2022, through June 30, 2023)