IR 05000327/2024001
| ML24106A181 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 04/17/2024 |
| From: | Louis Mckown Division Reactor Projects II |
| To: | Jim Barstow Tennessee Valley Authority |
| References | |
| IR 2024001 | |
| Download: ML24106A181 (12) | |
Text
SUBJECT:
SEQUOYAH, UNITS 1 AND 2 - INTEGRATED INSPECTION REPORT 05000327/2024001 AND 05000328/2024001
Dear Jim Barstow:
On March 31, 2024, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Sequoyah, Units 1 and 2. On April 9, 2024, the NRC inspectors discussed the results of this inspection with Tom Marshall, 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, 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:
Report Numbers:
05000327/2024001 and 05000328/2024001
Enterprise Identifier:
I-2024-001-0027
Licensee:
Tennessee Valley Authority
Facility:
Sequoyah, Units 1 and 2
Location:
Soddy Daisy, TN 37379
Inspection Dates:
January 1, 2024 to March 31, 2024
Inspectors:
D. Hardage, Senior Resident Inspector
A. Price, Resident Inspector
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 began the inspection period at rated thermal power (RTP). On March 3, 2024, the unit began end-of-life coast down. On March 22, 2024, the unit was at 85 percent RTP and shutdown for refueling outage 1R26. The unit remained shutdown for refueling the remainder of the 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
71111.01 - Adverse Weather Protection
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 severe weather due to impending freezing temperatures on January 11, 2024.
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) Spare 2-S 125-volt (V) vital battery charger alignment to vital battery board IV during scheduled preventative maintenance on vital battery charger IV on January 24, 2024.
- (2) Unit 2 A train component cooling water system (CCS) alignment following restoration of 2A2 CCS heat exchanger from cleaning on March 10, 2024.
- (3) Safety injection system alignment for low temperature overpressure protection in Mode 5 with the reactor coolant system (RCS) in a solid water configuration on March 23, 2024.
- (4) Unit 1 residual heat removal system (RHR) aligned for RCS cooldown in Mode 6 with RCS level below the flange on March 27, 2024.
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) Units 1 and 2 auxiliary building, elevation 653 on January 3, 2024.
- (2) Units 1 and 2 auxiliary building, elevation 690 on January 31, 2024.
- (3) Units 1 and 2 auxiliary building, elevation 669 on February 29, 2024.
- (4) Units 1 and 2 auxiliary building, elevation 749, electrical board, battery, and transformer rooms on March 6, 2024.
- (5) Units 1 and 2 auxiliary building, elevation 759 on March 21, 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 unannounced fire drill on January 31, 2024.
71111.06 - Flood Protection Measures
Flooding Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated internal flooding mitigation protections in the unit 1 and unit 2 auxiliary building, elevation 749, electrical board, battery, and transformer rooms on March 4, 2024.
71111.07A - Heat Exchanger/Sink Performance
Annual Review (IP Section 03.01) (1 Sample)
The inspectors evaluated readiness and performance of:
- (1) 2A1 CCS heat exchanger on February 12, 2024.
71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (2 Samples)
- (1) The inspectors observed and evaluated a simulator training scenario focused on refueling outage RHR operations including a loss of RHR while in mid-loop operations due to loss of offsite power with a diesel generator failure on February 27, 2024.
- (2) The inspectors observed and evaluated licensed operator performance in the main control room during shutdown and cooldown for refueling outage 1R26 on March 22, 2024.
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 2-FCO-030-246B, 480V transformer room ventilation supply damper operator due to the connecting rod separating from the damper, cause determination and evaluation (CDE) 3198, on January 25, 2024.
- (2) Maintenance rule CDE 3235 for the B electric board room chiller failure to start following maintenance on March 29, 2024.
71111.13 - Maintenance Risk Assessments and Emergent Work Control
Risk Assessment and Management Sample (IP Section 03.01) (4 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 1 and 2, week of January 21 thru 28, including protected equipment reviews for scheduled maintenance on 120V vital battery charger IV and 1B emergency diesel generator (EDG).
- (2) Week of January 29, including protected equipment review for repairs to the 2A safety injection pump (SIP) and review of the associated risk-informed-completion-time requirements on February 1, 2024.
- (3) Unit 1 and 2, week of February 25 thru March 1, including protected equipment review for scheduled maintenance on the unit 1 steam-driven auxiliary feedwater pump, cleaning of the 2A2 CCS heat exchanger and the A main control room chiller.
- (4) Unit 1, Yellow shutdown risk week of March 25-29, while RCS level was below the reactor flange level for reactor disassembly, including review of defense-in-depth protected equipment for 1R26.
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)1A and 2A EDG battery rack each have a tie rod completely corroded through on January 2, 2024.
(2)2A SIP oil analysis indicates an increase in metals, specifically chromium and nickel on January 30, 2024.
- (3) Unit 2 turbine-driven auxiliary feedwater pump had an unknown substance in the catch basin of the outboard pump bearing on February 1, 2024.
- (4) Scaffold supported by CCS piping above the 2B centrifugal charging pump on February 29, 2024.
- (5) Loss of backup containment penetration conductor overcurrent protective device for reactor coolant pump 1-2 on February 29, 2024.
- (6) Pressurizer power operated relief valve 1-PCV-68-340 failed initial close valve stroke time on March 23, 2024.
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) Design equivalent change package SQN-24-001. Change normal configuration of auxiliary feedwater LCVs to open on February 15, 2024.
71111.20 - Refueling and Other Outage Activities
Refueling/Other Outage Sample (IP Section 03.01) (1 Partial)
(1)
(Partial)
The inspectors evaluated unit 1 refueling outage 1R26 activities from March 22 thru March 31, 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) (4 Samples)
- (2) WO 119348977. Implement ECP 23886 (rev. 1) to replace QA essential raw cooling water pump packing on February 2, 2024.
- (3) WO 124228677. Replace 2A SIP pump shaft and bearings on February 4, 2024.
- (4) WO 124306595. Replace pressurizer pressure transmitter SQN-2-PT-068-0323 on March 18, 2024.
Surveillance Testing (IP Section 03.01) (3 Samples)
(1)2-PI-OPS-047-002.0, Steam Inlet Valve Testing on March 6, 2024.
(2)1-SI-OPS-088-001.0, Phase A Isolation Test on March 24, 2024.
(3)1-SI-OPS-082-026.B, Loss of Offsite Power with Safety Injection - D/G 1B-B Test on March 26, 2024.
Inservice Testing (IST) (IP Section 03.01) (1 Sample)
(1)1-SI-SXP-003-202.A, Motor Driven Auxiliary Feedwater Pump 1A-A Comprehensive Performance Test on March 22, 2024.
71114.06 - Drill Evaluation
Required Emergency Preparedness Drill (1 Sample)
- (1) Emergency preparedness training drill including a general emergency resulting from a loss of coolant accident with fuel failure and containment failure conducted on February 14,
OTHER ACTIVITIES - BASELINE
===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
BI01: Reactor Coolant System (RCS) Specific Activity Sample (IP Section 02.10)===
- (1) Unit 1 (January 1, 2023 through December 31, 2023).
- (2) Unit 2 (January 1, 2023 through December 31, 2023).
BI02: RCS Leak Rate Sample (IP Section 02.11) (2 Samples)
- (1) Unit 1 (January 1, 2023 through December 31, 2023).
- (2) Unit 2 (January 1, 2023 through December 31, 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) Condition report (CR) 1697913. Low margin for motor-driven auxiliary feedwater pump 1B-B.
- (2) CR 1916599. Technical Requirement (TR) 7.5.3 assessment on nonfunctional seismic monitors 0-XT-52-75A and 0-XT-52-75B.
INSPECTION RESULTS
No findings were identified.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On April 9, 2024, the inspectors presented the integrated inspection results to Tom Marshall, site vice president, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Corrective Action
Documents
CR 1902428
Freeze Protection Issue 0-PI-OPS-000-006.0
01/11/2024
Procedures
0-PI-OPS-000-
006.0
Freeze Protection
Revision 74
0-SO-250-1
25 Volt DC Vital Power System
Revision 88
1-SI-OPS-068-
001.1
Low Temperature Overpressure Protection
Revision 13
2-SO-62-5
Revision 70
Procedures
2-SO-70-1,
Component Cooling Water System "A" Train Valve Checklist
10/17/2021
Corrective Action
Documents
Resulting from
Inspection
CR 1913750
Scaffold in contact with piping for shutdown board room air
handling units
2/29/2024
AUX-0-653-00
Fire Protection Pre Fire Plans Auxiliary Building - El. 653
Revision 9
AUX-0-690-01
Fire Protection Pre Fire Plans Auxiliary Building (El. 690 Unit
Side)
Revision 9
AUX-0-690-02
Fire Protection Pre Fire Plans Auxiliary Building (El. 690 Unit
Side)
Revision 9
AUX-0-749-01
Fire Protection Pre Fire Plans Auxiliary Building (El. 749 Unit
Side)
Revision 13
AUX-0-749-02
Fire Protection Pre Fire Plans Auxiliary Building (El. 749 Unit
Side)
Revision 14
AUX-0-759-01
Fire Protection Pre-Fire Plans
Auxiliary Building (El. 759 Unit 1 Side)
Revision 6
AUX-0-759-02
Fire Protection Pre-Fire Plans
Auxiliary Building (El. 759 Unit 2 Side)
Revision 7
Fire Plans
PFP NO: FPH
Fire Protection Pre-Fire Plans
Fire Pump House
Revision 1
Calculations
MDN-000-000-
2010-0203
SQN Probabilistic Risk Assessment - Internal Flooding
Analysis
Revision 6
Procedures
Revision 8
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Work Orders
2A1 CCS heat exchanger clam and mic inspection
2/20/2024
CR 1819324
Operator connecting rod separated from dampers
11/26/2022
CR 1909937
"B" Electric Board Room Chiller failed to startup during PMT
run
2/14/2024
Corrective Action
Documents
Remove/Replace B-B EBR Chiller Compressor Motor Starter
2/12/2024
NPG-SPP-03.4
Maintenance Rule Performance Indicator Monitoring,
Trending and Reporting - 10CFR50.65
Revision 5
Procedures
TI-4
Maintenance Rule Performance Indicator Monitoring
Trending, and Reporting - 10CFR50.65
Revision 39
Work Orders
B Electric Board Room Chiller failed to startup during PMT
03/05/2024
CR 1906501
NRC identified boric acid build up on 2BB safety injection
casing flange and vent valve
01/29/2024
Corrective Action
Documents
Resulting from
Inspection
CR 1920063
NRC identified protected equipment barrier missing and
scaffold touching flex conduit in 1A RHR pump room
03/27/2024
Procedures
0-GO-16
System Operability Checklists
Revision 36
CR 1900954
2AA SIP oil analysis
01/03/2024
CR 1913939
1B 6.9KV unit board control power auto transferred to
alternate
2/29/2024
Corrective Action
Documents
CR 1914385
TR 3.7.5 condition report - 1B 6.9KV Unit Board BD control
power transfer
03/01/2024
CR 1900168
Significant Corrosion on EDG battery rack tie rods
2/27/2023
CR 1907411
NRC identified unknown substance U2 TDAFW stuffing box
gland
2/01/2024
Corrective Action
Documents
Resulting from
Inspection
CR 1913856
Scaffold attached to safety related piping
2/29/2024
Work Orders
Perform flush and CUNO inspection
01/30/2024
CR 1919426
White powder (boric acid or sodium tetraborate) behind the
base of pressurizer
03/25/2024
Corrective Action
Documents
Resulting from
Inspection
CR 1919430
Leak on component cooling water line to RCP 1-2 thermal
barrier
03/25/2024
Procedures
0-SI-SXX-068-
27.0
RCS and Pressurizer Temperature and Pressure Limits
Revision 17
CR 1918307
MFP speed probe deviation alarms during AFW
comprehensive test
03/20/2024
Corrective Action
Documents
CR 1918999
Procedure change request - AFW Pump Comprehensive
03/23/2024
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Tests
CR 1919433
ERCW pump L-B would not start manually as directed 1-SI-
03/26/2024
2-SI-ICC-068-
23.3
Channel Calibration of Pressurizer Pressure Channel III,
Rack 9, Loop 2-P-68-323
Revision 21
2-SI-SXP-063-
201.A
Safety Injection Pump 2A-A Performance Test
Revision 29
Procedures
MI-6.9
Safety Injection Pump Inspection and Rebuild
Revision 23
71151
Corrective Action
Documents
CR 1851189
Unit 2 SI-137.0 unidentified leakage at Action Level II
04/19/2023
CR 1697633
1B MDAFW Pump DP below acceptance criteria
05/29/2021
Corrective Action
Documents
CR 1697806
MDAFW critical spare exhibited marginal performance
05/31/2021
EWR 21-DEM-
003-076
MDAFWP pump curve (generic location)
Revision 2
Engineering
Evaluations
SQN-0-24-017
PRA Evaluation for seismic monitors nonfunctionality
03/12/2024