IR 05000327/2025001
| ML25126A163 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 05/08/2025 |
| From: | Renee Taylor NRC/RGN-II/DORS/PB5 |
| To: | Erb D Tennessee Valley Authority |
| References | |
| IR 2025001 | |
| Download: ML25126A163 (1) | |
Text
SUBJECT:
SEQUOYAH UNITS 1 AND 2 - INTEGRATED INSPECTION REPORT 05000327/2025001, 05000328/2025001, AND 07200034/2025001
Dear Delson Erb:
On March 31, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Sequoyah Units 1 and 2. On April 15, 2025, the NRC inspectors discussed the results of this inspection with Ricardo Medina, Site Regulatory Compliance Manager, 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, Ryan C. Taylor, Chief Projects Branch 5 Division of Operating Reactor Safety Docket Nos. 05000327, 05000328, and 07200034 License Nos. DPR-77 and DPR-79
Enclosure:
As stated
Inspection Report
Docket Numbers:
05000327, 05000328, and 07200034
License Numbers:
Report Numbers:
05000327/2025001, 05000328/2025001, and 07200034/2025001
Enterprise Identifier:
I-2025-001-0031 and I-2025-001-0085
Licensee:
Tennessee Valley Authority
Facility:
Sequoyah Units 1 and 2
Location:
Soddy-Daisy, TN
Inspection Dates:
January 1, 2025 to March 31, 2025
Inspectors:
W. Deschaine, Senior Project Engineer
P. Meier, Senior Resident Inspector
D. Neal, Health Physicist
A. Ponko, Senior Construction Project Inspector
A. Price, Resident Inspector
J. Vasquez, Construction Project Inspector
Approved By:
Ryan C. Taylor, Chief
Projects Branch 5
Division of Operating Reactor Safety
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 approximately 100 percent rated thermal power and remained there through the end of the period.
Unit 2 began the inspection period in mode 5. On January 14, 2025, the unit entered mode 4 in preparation for reactor start-up and testing. Mode 3 was entered on January 15, 2025. Mode 2 and reactor criticality was achieved on January 17, 2025, for reactor low power physics testing. Following reactor testing on January 17, 2025, the reactor was manually tripped and eventually cooled down to mode 5 on January 18, 2025. Unit 2 remained in mode 5 through the end of the 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
Seasonal Extreme Weather Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated the adequacy of the overall preparations to protect risk significant systems from impending severe weather due to severe thunderstorms and potential tornadoes on March 15, 2025.
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) Unit 2 "B" train containment spray system prior to transitioning to mode 4 following a refueling outage during the week of January 13, 2025
- (2) Unit 2 "A" and "B" train safety injection system on January 14, 2025
- (3) Unit 2 "A" and "B" train motor-driven auxiliary feedwater system on January 15, 2025
- (4) Essential raw cooling water system associated with the protected emergency diesel generators during the 2A emergency diesel generator planned maintenance outage during the week of January 27, 2025
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)
"A" train 6.9kV shutdown board room (auxiliary building elevation 734) on January 15, 2025
- (2) Unit 1 auxiliary building elevation 690 corridor (FA 690-A01) on January 30, 2025
- (3) Unit 1 auxiliary building ventilation and purge air room (FA 714-A-5) on January 30, 2025 (4)
"B" train 6.9KV shutdown board room (auxiliary building elevation 734) on March 20, 2025
- (5) Fire pump house on March 20, 2025
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 in a temporary building north of the switchyard on March 18, 2025.
71111.06 - Flood Protection Measures
Flooding Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated the licensee's external flood protection plan and operational readiness during the weeks of February 17, 2025, and February 24, 2025 (AOP-N.03).
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 inspectors observed and evaluated licensed operator performance in the control room for the following activities:
- Unit 2 preparations for mode 4 entry on January 13, 2025
- Unit 2 reactor startup for low power physics testing on January 17, 2025
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed and evaluated a cycle 25-1 simulator exam involving a steam generator tube scenario on February 3, 2025.
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 remain capable of performing their intended function:
(1)1B emergency diesel generator relay failure on February 20, 2025 (condition report (CR) 1993337)
- (2) High pressure fire protection system (system 26) on March 31, 2025 (CRs 1332919,
===1882748, and 1897409)
71111.13 - Maintenance Risk Assessments and Emergent Work Control
Risk Assessment and Management Sample (IP Section 03.01)===
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 2 Eagle 21 rack 6 issues resulting in inoperability of the low temperature overpressure protection system on January 1, 2025 (work order (WO) 125046222; CR 1982388)
- (2) Unit 2 A train residual heat removal pump flow control valve air-line pipe support repair with the pump in operation for cooling while in mode 5 on January 8, 2025 (WO
===125057566)
- (3) Unit 2 loop two atmospheric relief valve erratic cycling identified while heating up to mode 3 on January 14, 2025 (CR 1984711)
- (4) Unit 1 risk associated with the 2A emergency diesel generator planned maintenance outage during the week of January 27, 2025 (5)1A emergency diesel generator and unit 2 "A" train charging pump planned maintenance outages during the week of February 10, 2025
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01)===
The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:
- (1) Unit 1 A train 6.9kv shutdown board compartment current transformer melting identified on December 30, 2024 (CR 1982118)
- (2) Unit 2 Eagle 21 rack 6 issues resulting in inoperability of the low temperature overpressure protection system on January 1, 2025 (CR 1982388)
- (3) Unit 2 A train motor-driven auxiliary feedwater pump trip alarm following a manual stop identified on January 13, 2025, just prior to entering mode 3 (CR 1984508)
(4)shutdown board room cooling system unavailability and its potential operability concern as a support system (attendant equipment) for the vital 6.9kv safety-related distribution boards (CR 1742723; CR 1974348)
- (5) Void found in the unit 1 emergency boration line, identified on February 18, 2025 (CR
===1992886)
- (6) Unit 1 emergency raw cooling water flood mode valve (1-VLV-70-688) stroke failure identified on February 19, 2025 (CR 1993223)
- (7) Unit 1 control rod position deviations identified on February 21, 2025, and February 23, 2025 (CR 1993696; 1994099)
- (8) Unit 1 intermediate range detector (N35) intermittently failing impacting post-accident monitoring instrumentation identified on March 4, 2025 (CR 1996114)
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 (IP Section 03.01)===
- (1) Unit 2 Eagle 21 rack 6 repair and operability restoration of the low temperature overpressure protection system on January 2, 2025 (WO 125046222; CR 1982388)
- (2) N-B essential raw cooling water pump testing following pump replacement on January 6, 2025 (WO 124600060, 123156279; CR 1866767)
- (3) Unit 2 reactor building air lock testing before entering mode 4 performed on January 12, 2025 (WO 124244945; 2-SI-SLT-088-259.2)
- (4) Unit 2 safety injection/residual heat removal hot leg primary check valve integrity test following maintenance on 2-VLV-63-558 on January 15, 2025 (2-SI-SXV-063-204.0, WO 123728773)
- (5) Unit 2 turbine driven auxiliary feedwater pump testing following maintenance and prior to mode 2 entry on January 16, 2025 (WO 124220147)
(6)2A emergency diesel generator testing following electric governor speed controller and air start motor replacements on January 31, 2025 (WOs 124312254; 122738082)
- (7) Unit 1 A train residual heat removal pump breaker replacement on February 12, 2025 (WO 124223750, 124801157)
Surveillance Testing (IP Section 03.01) (5 Samples)
- (1) Unit 2 residual heat removal cold leg primary and secondary check valve integrity test on January 14, 2025 (2-SI-SXV-063-206.0)
- (2) Unit 1 rod position and group demand position indicator surveillance performed on February 4, 2025 (0-SI-OPS-085-11.0)
(3)1A emergency diesel generator surveillance run on February 14, 2025 (WO
===124310185; 1-SI-OPS-082-007.A) (4)1A emergency diesel generator 24-hour surveillance performed on March 11 and 12, 2025 (1-SI-OPS-082-024.A)
(5)1B emergency diesel generator hot restart and load reject tests performed on March 19, 2025 (1-SI-OPS-082-024.B)
Inservice Testing (IP Section 03.01)===
- (1) Unit 2 "A" train residual heat removal pump comprehensive performance test on March 14, 2025 (2-SI-SXP-074-201.A)
- (2) Unit 1 A train motor-driven auxiliary feedwater pump test performed on March 31, 2025 (1-SI-SXP-003-201.A)
71114.06 - Drill Evaluation
Additional Drill and/or Training Evolution (1 Sample)
The inspectors evaluated:
- (1) A licensed operator training scenario in the simulator associated with a steam generator tube rupture and emergency declaration that contributed to the drill and exercise performance indicator on February 3,
OTHER ACTIVITIES - BASELINE
===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
BI01: Reactor Coolant System Specific Activity Sample (IP Section 02.10)===
- (1) Unit 1 (January 1 through December 31, 2024)
- (2) Unit 2 (January 1 through December 31, 2024)
BI02: Reactor Coolant System Leak Rate Sample (IP Section 02.11) (2 Samples)
- (1) Unit 1 (January 1 through December 31, 2024)
- (2) Unit 2 (January 1 through December 31, 2024)
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) Auxiliary building purge air supply vent found open impacting the auxiliary building gas treatment system identified on January 13, 2025 (CR 1984581)
- (2) Unit 1 plant equipment requiring additional monitoring using an "adverse condition monitoring plan" to ensure corrective action effectiveness or to ensure availability /
operability before final corrective actions
OTHER ACTIVITIES
- TEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL
===60855 - Operation Of An ISFSI Inspections were conducted using the appropriate portions of the 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) 2690, Inspection Program for Storage of Spent Reactor Fuel and Reactor-Related Greater-than-Class C Waste at Independent Spent Fuel Storage Installations (ISFSI) and for 10 CFR Part 71 Transportation Packagings."
Operation Of An ISFSI===
- (1) From February 3 - 7, 2025 the inspectors performed a review of the licensees ISFSI activities to verify compliance with regulatory requirements. During the on-site inspection, the inspectors observed and reviewed licensee activities in each of the five safety focus areas including occupational exposure, public exposure, fuel damage, confinement, and impact to plant operations.
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. Additionally, the inspectors performed independent walkdowns of the heavy load lifting equipment, the ISFSI haul path, and the ISFSI pad.
INSPECTION RESULTS
No findings were identified.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On February 13, 2025, the inspectors presented the Operation of an ISFSI inspection results to Mr. Tom Marshall, Site Vice President, and other members of the licensee staff.
- On April 15, 2025, the inspectors presented the integrated inspection results to Mr.
Ricardo Medina, Site Regulatory Compliance Manager, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
60855
Calculations
No: 48N703
Qualification of crane and rail bumper for 125 ton crane
60855
Miscellaneous
Welding and NDE records
60855
Miscellaneous
Fuel selection and verification documents
60855
Procedures
Cask processing procedures
60855
Radiation
Surveys
Radiation surveys of ISFSI pad
Corrective Action
Documents
CR 1563188
Unit 1 MSR chevron degradation
11/04/2018
Corrective Action
Documents
CR 1760646
BETA annunciator system degraded causing nuisance
alarms
03/09/2022
Corrective Action
Documents
CR 1922292
Containment spray heat exchanger obstructed tubes
04/05/2024
Corrective Action
Documents
CR 1927818
SI pump discharge header pressurizing to RCS pressure
04/29/2024
Corrective Action
Documents
CR 1948701
1A1/1A2 component cooling system heat exchanger fouling
08/06/2024
Corrective Action
Documents
CR 1966486
Main generator oil leakage
10/18/2024
Corrective Action
Documents
CR 1966765
Exciter - following repairs
10/19/2024
Corrective Action
Documents
CR 1982281
Stator cooling water dissolved oxygen
2/31/2024