IR 05000327/2022002
| ML22209A243 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 08/01/2022 |
| From: | Louis Mckown Division Reactor Projects II |
| To: | Jim Barstow Tennessee Valley Authority |
| References | |
| IR 2022002 | |
| Download: ML22209A243 (13) | |
Text
SUBJECT:
SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2 - INTEGRATED INSPECTION REPORT 05000327/2022002 AND 05000328/2022002
Dear Mr. Barstow:
On June 30, 2022, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Sequoyah Nuclear Plant, Units 1 and 2. On July 19, 2022, 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, 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:
05000327/2022002 and 05000328/2022002
Enterprise Identifier:
I-2022-002-0027
Licensee:
Tennessee Valley Authority
Facility:
Sequoyah Nuclear Plant, Units 1 and 2
Location:
Soddy Daisy, TN 37379
Inspection Dates:
April 01, 2022 to June 30, 2022
Inspectors:
N. Childs, Senior Project Engineer
D. Hardage, Senior Resident Inspector
Approved By:
Louis J. McKown, 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 Nuclear Plant, 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) and remained at or near RTP for the entire inspection period.
Unit 2 began the inspection period at RTP. On June 1, 2022, the unit reduced power to 20 percent RTP and removed the turbine from service to perform repairs on the main transformer neutral bus. On June 9, 2022, the turbine was returned to service and the unit was returned to RTP on June 10, 2022. The unit remained at or near RTP for the remainder 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 readiness for seasonal extreme weather conditions prior to the onset of seasonal summer temperatures including review the material condition of the plants offsite AC power systems and onsite alternate AC power systems, including the switchyard and transformers on May 11, 2022.
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) Vital Instrument Board 2-I with vital invertor 2-I out of service for functional testing on April 5, 2022
- (2) Unit 1 auxiliary feedwater (AFW) system following testing of 1A AFW pump testing on April 8, 2021
- (3) Unit 2 A train component cooling water (CCS) after restoration from 2A2 CCS heat exchanger cleaning on April 28, 2022
- (4) Unit 1 and 2 offsite power while the Unit 2 Unit Station Service Transformers were out of service for corrective maintenance on the main transformer neutral bus on June 8, 2022
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 690 on April 20, 2022
- (2) Unit 1 and Unit 2 Auxiliary Building, Elevation 714 on April 27, 2022
- (3) Unit 1 and Unit 2 Auxiliary Building, Elevation 653 on May 18, 2022
- (4) Unit 1 and Unit 2 Auxiliary Instruments Rooms, Control Building, Elevation 685 on June 2, 2022
- (5) Unit 1 and Unit 2, Control Building, Elevation 669 on June 12, 2022
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 at the Unit 1 lube oil storage tank in the Turbine Building on April 13, 2022.
71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance
Licensed Operator Performance in the Actual Plant/Main Control Room (IP Section 03.01) (2 Samples)
- (1) The inspectors observed and evaluated licensed operator performance in the main control room during Unit 2 main generator NERC reactive load testing on April 16, 2022.
- (2) The inspectors observed and evaluated licensed operator performance in the main control room during an emergent Unit 2 downpower to take the main transformer offline following neutral bus disconnection on June 1, 2022.
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed and evaluated a simulator examination scenario including a large break loss of coolant accident, loss of a safety related 6.9Kv bus and failure of phase B containment isolation valves to automatically close on June 6, 2022.
71111.12 - Maintenance Effectiveness
Maintenance Effectiveness (IP Section 03.01) (1 Sample)
The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components (SSCs) remain capable of performing their intended function:
- (1) Failure of Unit Station Service Transformer 1B on-load tap changer (CDE 3157) to automatically lower tap positions when demanded on August 5, 2021
Aging Management (IP Section 03.03) (2 Samples)
The inspectors evaluated the effectiveness of the aging management program for the following SSCs that did not meet their inspection or test acceptance criteria:
(1)18-inch essential raw cooling water (ERCW) piping downstream of containment spray (CS) heat exchanger throttle valve 2-VLV-067-0537A (CR 1668098)
- (2) Auxiliary building general ventilation system air handling unit 1-AHU-313-642 fan housing corrosion (CR 1717877)
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) Unit 1 and 2, week of April 17-23, 2022, including protection equipment reviews for scheduled maintenance on the 2A2 component cooling water heat exchanger, and emergent failure of Unit 2 Steam Generator 3 Auxiliary Feedwater Level Controller.
- (2) Unit 1 and 2, week of April 24-30, 2022, including protection equipment reviews for scheduled maintenance on the 0B2 component cooling water heat exchanger, and the 2B centrifugal charging pump.
- (3) Unit 1 and 2, week of May 8-14, 2022, including planned maintenance on B station air compressor, emergent maintenance on 2B generator bus duct cooling fan including protection equipment reviews, and a conservative operations alert.
- (4) Unit 1 and 2, week of May 29-June 4, 2022, including planned maintenance on C and D common station service transformers, and emergent maintenance on the Unit 2 main transformer neutral bus which required removing unit 2 main turbine from service.
- (5) Unit 1 and 2, week of June 5-June 11, 2022, including planned maintenance on C common station service transformer, and emergent repair of the Unit 2 main transformer including startup of the Unit 2 main turbine and return to RTP.
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (4 Samples)
The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:
- (1) Unit 2 unsealed floor drain in upper containment on April 22, 2022
- (2) Immediate Determination of Operability for low ERCW flow to the 1A CS heat exchanger on May 24, 2022
- (3) Prompt Determination of Operability for multiple ERCW leaks on CCS/AFW Pump Area Cooler A-A on June 5, 2022
- (4) Past Operability Evaluation for gas discharge from 1B residual heat removal suction piping on June 9, 2022
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) ECP 23874 Fuel Transfer System Upgrades
71111.19 - Post-Maintenance Testing
Post-Maintenance Test Sample (IP Section 03.01) (3 Samples)
The inspectors evaluated the following post-maintenance testing activities to verify system operability and/or functionality:
- (1) Work Order (WO) 122262217, Perform a clam and mic inspection on 2A2 CCS Heat Exchanger, on April 22, 2022
- (2) WO 122920826, Replace 2B Isophase bus duct cooling fan motor, on May 15, 2022
- (3) WO 122973254, CCS and AFW Pump Cooler A-A - Replace Cooler Coil, on June 6, 2022
71111.22 - Surveillance Testing
The inspectors evaluated the following surveillance testing activities to verify system operability and/or functionality:
Surveillance Tests (other) (IP Section 03.01) (3 Samples)
(1)1-SI-SXP-003-201.A, Motor Driven Auxiliary Feedwater Pump 1A-A Performance Test, on April 6, 2022 (2)2-PI-OPS-047-002.0, Steam Inlet Valve Testing, on April 28, 2022 (3)1-PI-OPS-047-723.0, Unit 1 Turbine Trip Block Solenoid Valve Test, on May 4, 2022
FLEX Testing (IP Section 03.02) (1 Sample)
(1)0-PI-SFT-360-001.0, Flex Pumps Operating Instructions for Maintenance Activities, on June 15, 2022
71114.06 - Drill Evaluation
Drill/Training Evolution Observation (IP Section 03.02) (1 Sample)
The inspectors evaluated:
- (1) Emergency preparedness training drill involving an extended loss of all AC power resulting in a general emergency conducted on April 20,
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 (April 2021 through March 2022)
- (2) Unit 2 (April 2021 through March 2022)
IE03: Unplanned Power Changes per 7000 Critical Hours Sample (IP Section 02.02) (2 Samples)
- (1) Unit 1 (April 2021 through March 2022)
- (2) Unit 2 (April 2021 through March 2022)
IE04: Unplanned Scrams with Complications (USwC) Sample (IP Section 02.03) (2 Samples)
- (1) Unit 1 (April 2021 through March 2022)
- (2) Unit 2 (April 2021 through March 2022)
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) CR 1727625 Resolution of fuel transfer system exceeding overload setpoint needed
- (2) CR 1748187 PRT venting is excessive.
71152S - Semiannual Trend Problem Identification and Resolution Semiannual Trend Review (Section 03.02)
- (1) The inspectors reviewed the licensees corrective action program for potential adverse trends with the long-term installation of scaffolding that might be indicative of a more significant safety issue.
71153 - Follow Up of Events and Notices of Enforcement Discretion Event Followup (IP Section 03.01)
- (1) The inspectors evaluated the circumstances surrounding a notice of unusual event (NOUE) due to unexpected seismic monitoring alarms and the licensees response on April 29, 2022.
Personnel Performance (IP Section 03.03) (1 Sample)
- (1) The inspectors evaluated licensee performance in response to Unit 2 failure of the Main Transformer and associated downpower on June 2,
INSPECTION RESULTS
No findings were identified.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
On July 19, 2022, the inspectors presented the integrated inspection results to Mr. Tom Marshall and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
CR 1744025
MODs in the 161KV Switchyard in a degraded state, leading
to operator burdens and safety issues
2/24/2021
Corrective Action
Documents
CR 1775628
Perform overhaul of 2B Gen Bus Cooling Fan
05/11/2022
Corrective Action
Documents
Resulting from
Inspection
CR 1775623
Temporary Equipment near B/U Security D/G
05/11/2022
0-SI-OPS-082-
007.W
AC Electrical Power Source Operability Verification
Revision 45
0-SO-250-2
20 Volt AC Vital Instrument Power System
Revision 75
1-SO-3-2
Auxiliary Feedwater System
Revision 62
2-SO-70-1
Component Cooling Water System "A" Train Power
Checklist 2-70-1.02
Revision 10
Procedures
2-SO-70-1
Component Cooling Water System "A" Train Valve Checklist
2-70-1.03
Revision 19
Corrective Action
Documents
Resulting from
Inspection
CR 1772110
Several items left in overhead above CCS mezzanine-AB
690
04/26/2022
AUX-0-653-00
Pre-Fire Plan Auxiliary Building - El. 653
Revision 9
AUX-0-690-01
Pre-Fire Plan Auxiliary Building - El. 690 (Unit 1 Side)
Revision 9
AUX-0-690-2
Pre-Fire Plan Auxiliary Building El. 690 (Unit 2 side)
Revision 9
AUX-0-714-01
Pre-Fire Plan Auxiliary Building - El. 714 (Col. A1-15, Q-U)
Revision 11
Fire Plans
AUX-0-714-02
Pre-Fire Plan Auxiliary Building - El. 714 (Col. U-X and U1 &
U2 Additional Equip. Builds.)
Revision 9
Miscellaneous
SEG#
OPL273E2241
Cycle 22-4 Simulator Exam 1
Revision )
Procedures
2-PI-ENG-SERC
SERC Verification and Data Reporting of the SQN U2 Main
Generator Real and Reactive Power Capability
Revision 4
CR 1712648
USST 1B tap changer not tapping
08/06/2022
Corrective Action
Documents
CR 1720709
Aging Management Program Evaluation Needed for 1-AHU-
313-642 Fan Housing Corrosion
09/13/2021
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
0-TPP-DXX-000-
100.14
License Renewal Aging Management Program Basis
Document Internal Surfaces in Miscellaneous Piping and
Ducting Components Program
Revision 2
0-TPP-DXX-000-
100.38
License Renewal Aging Management Program Basis
Document Service Water Integrity Program
Revision 0
NEDP-21
License Renewal Program
Revision 10
NEDP-21.0.2
License Renewal Activities Prior to Period of Extended
Operation
Revision 1
Procedures
TI-4
Maintenance Rule Performance Indicator Monitoring,
Trending, and Reporting - 10CFR50.65
Revision 38
Work Orders
18-inch ERCW Piping Downstream of 2-VLV-67-537A
Proactive Mitigation
Revision 0
CR 1775437
DFR work and COA
05/11/2022
Corrective Action
Documents
CR 1775447
2B bus duct cooling fan high vibration and noise
05/11/2022
0-GO-16
System Operability Checklists
Revision 32
0-SI-OPS-082-
007.W
AC Electrical Power Source Operability Verification
Revision 45
Procedures
NPG-SPP-07.3.4
Protected Equipment
Revision 12
Calculations
30-D053-EPM-
BVC-052788
Determination of Required ERCW and Air Flow Rates to
ESF Room Coolers
Revision 10
CR 1778610
Low ERCW flow for the 1A containment spray heat
exchanger
05/24/2022
Corrective Action
Documents
CR 1778964
OPDP-8 IDO not performed correctly
05/25/2022
ACMP 22-018
Adverse condition monitoring plan (ACMP) for 1A
containment spray heat exchanger ERCW flow
06/02/2022
EWR 22-DEM-
067-061
Information to support IDO for CR 1778610
05/25/2022
SO-22-018
Sequoyah operations department standing order for 1A
containment spray heat exchanger
06/02/2022
Miscellaneous
SQN Design
Criteria SQN-DC-
V-21.0
Environmental Design
Revision 30
Operability
Evaluations
CAR 1762356-
001
Past Operability Evaluation Documentation for CR 1762356
04/02/2022
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
CR 1780764
PDO for A-A CCS and AFW pump area cooler isolated for
ERCW leakage
07/05/2022
Procedures
0-SO-30-10
Auxiliary Building Ventilation System
Revision 72
0-MI-MRR-070-
611.0
Component Cooling System Heat Exchanger Maintenance
Revision 16
0-PI-SFT-067-
001.A
ERCW Train A Flow Monitoring
Revision 6
Procedures
0-SI-SXI-000-
201.0
ASME Section XI Inservice Pressure Test
Revision 25
Corrective Action
Documents
Resulting from
Inspection
CR 1772024
Simulator programing, RCS model boundary flow area for
CVCS set to 0.0
04/26/2022
CR 1773425
On 4/27, PORV tailpipe temperature high alarm received
05/03/2022
CR 1774563
PORV tailpipe temperature began to rise from 110deg
05/07/2022
Corrective Action
Documents
CR 1777618
Tracking CR for ACMP U1 PORV tailpipe temperature
05/19/2022
CR 1758645
NRC-identified unsatisfactory housekeeping in Unit 1 el. 690
Pipe Chase
03/01/2022
CR 1758645
NRC identified unsatisfactory housekeeping in Unit 2 el 690
and 669 pipe chase
03/04/2022
CR 1768207
Unlabeled Scaffolding in 669 pen room
04/07/2022
Corrective Action
Documents
CR 1777740
Housekeeping, Scaffolding Removal, U-2 Aux Instrument
Room
05/20/2022
Corrective Action
Documents
Resulting from
Inspection
CR 1768277
Deficiencies identified with the Scaffold Program at SQN
04/08/2022
Procedures
MMTP-102
Erection of Scaffolds/Temporary Work Platforms and
Ladders
Revision 21