IR 05000327/2022004
| ML23041A069 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 02/10/2023 |
| From: | Louis Mckown NRC/RGN-II/DRP/RPB5 |
| To: | Jim Barstow Tennessee Valley Authority |
| References | |
| EA-17-022, EA-2022-072 IR 2022004 | |
| Download: ML23041A069 (1) | |
Text
February 10, 2023
SUBJECT:
SEQUOYAH, UNITS 1 AND 2 - INTEGRATED INSPECTION REPORT 05000327/2022004 AND 05000328/2022004
Dear Mr. Barstow:
On December 31, 2022, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Sequoyah, Units 1 and 2. On January 30, 2023, the NRC inspectors discussed the results of this inspection with Thomas Marshall and other members of your staff. The results of this inspection are documented in the enclosed report.
One finding of very low safety significance (Green) is documented in this report. This finding involved a violation of NRC requirements. We are treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2 of the Enforcement Policy.
A licensee-identified violation which was determined to be of very low safety significance is documented in this report. We are treating this violation as a non-cited violation (NCV)
consistent with Section 2.3.2 of the Enforcement Policy.
If you contest the violations or the significance or severity of the violations documented in this inspection report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN:
Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region II; the Director, Office of Enforcement; and the NRC Resident Inspector at Sequoyah, Units 1 and 2.
If you disagree with a cross-cutting aspect assignment in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your disagreement, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555-0001; with copies to the Regional Administrator, Region II; and the NRC Resident Inspector at Sequoyah, Units 1 and 2. In addition, the Regional Administrator has authorized staff to use IP 92702, Follow-Up on Traditional Enforcement Actions Including Violations, Deviations, Confirmatory Action Letters, and Orders, to perform follow-up inspections of the 2017 Confirmatory Order (CO) at Tennessee Valley Authority (TVA) Corporate, Browns Ferry, Sequoyah and Watts Bar because these follow-up inspections are not part of the reactor oversight program (ROP) baseline inspections.
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, Signed by McKown, Louis on 02/10/23 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: 05000327/2022004 and 05000328/2022004 Enterprise Identifier: I-2022-004-0027 Licensee: Tennessee Valley Authority Facility: Sequoyah, Units 1 and 2 Location: Soddy Daisy, TN 37379 Inspection Dates: October 01, 2022 to December 31, 2022 Inspectors: J. Bell, Health Physicist A. Goldau, Operations Engineer D. Hardage, Senior Resident Inspector M. Keefe-Forsyth, Safety Culture Program Mgr N. Lacy, Operations Engineer M. Magyar, Reactor Inspector A. Nielsen, Senior Health Physicist S. Ninh, Senior Project Engineer A. Price, Resident Inspector J. Rivera, Health Physicist Approved By: Louis J. McKown, II, Chief Reactor Projects Branch 5 Division of Reactor Projects Enclosure
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. A licensee-identified non-cited violation is documented in report section: 71124.0
List of Findings and Violations
Unauthorized entry into a High Radiation Area Cornerstone Significance Cross-Cutting Report Aspect Section Occupational Green [H.12] - Avoid 71124.01 Radiation Safety NCV 05000327,05000328/2022004-01 Complacency Open/Closed A self-revealing, Green, Non-cited Violation (NCV) of Technical Specification (TS) 5.7.1 was identified for a worker who improperly entered a posted high radiation area (HRA).
Specifically, the worker entered the HRA without being logged onto an appropriate radiation work permit (RWP) and without being knowledgeable of dose rates in the area prior to entry.
Additional Tracking Items
Type Issue Number Title Report Section Status URI 05000327/2022003-01 1B-B centrifugal charging 71153 Closed pump (CCP) unable to maintain Pressurizer Level at power LER 05000327/2022-001-00 LER 2022-001-00 for 71153 Closed Sequoyah Nuclear Plant,
Unit 1 regarding Failure of 1B-B Centrifugal Charging Pump Results in Condition Prohibited by Technical Specifications
PLANT STATUS
Unit 1 began the inspection at 100 percent rated thermal power (RTP). On October 1, 2022, the unit began end of life coastdown. On October 21, 2022, the unit was at 83 percent RTP and shutdown for refueling outage 1R25. On November 23, 2022, the reactor was started up and the unit was returned to RTP on November 27, 2022. The unit remained at or near RTP for the remainder of the inspection period.
Unit 2 operated at or near rated thermal power 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
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 cold temperatures for the following systems on December 22, 2022 :
Unit 1 and 2 Refueling Water Storage Tanks Unit 1 and 2 Main Steam Valve Vaults
71111.04 - Equipment Alignment
Partial Walkdown Sample (IP Section 03.01) (5 Samples)
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
- (1) Unit 1 safety injection (SI) train B components after restoration from 1B-B SI pump casing, suction, and discharge piping vent on October 13-14, 2022
- (2) 1A emergency diesel generator (EDG) while 1B EDG was out of service for an emergent fuel oil leak on October 24, 2022
- (3) Unit 1 residual heat removal (RHR) system with both trains in service for cooldown in Mode 5 with reactor coolant system (RCS) level below the flange on October 26, 2022
- (4) Unit 1 emergency core cooling system (ECCS) lineup in the Main Control Room following November outage on December 20, 2022
- (5) Unit 1 turbine driven auxiliary feedwater pump (TDAFW) lineup following November outage on December 21, 2022
71111.05 - Fire Protection
Fire Area Walkdown and Inspection Sample (IP Section 03.01) (4 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 Reactor Building Annulus on November 17, 2022
- (2) Unit 1 Lower Containment on November 17, 2022
- (3) Unit 1 Upper Containment on November 17, 2022
- (4) Unit 1 and Unit 2 Auxiliary Building, Elevation 669 on December 19, 2022
71111.08P - Inservice Inspection Activities (PWR) PWR Inservice Inspection Activities Sample (IP Section 03.01)
- (1) The inspectors evaluated pressurized water reactor non-destructive testing by reviewing the following examinations from October 31 - November 3, 2022:
1. Ultrasonic Testing (UT)a. SIF 193, Pipe to Valve weld, Class 1 (reviewed)b. SIF 194, Valve to Elbow weld, Class 1 (reviewed)c. CRDM 2 Nozzle, ASME Class 1 (observed)d. CRDM 9 Nozzle, ASME Class 1 (observed)e. UHI 26 Nozzle, ASME Class 1 (observed)2. Visual Inspection (VT)a. Thermal Sleeve 60 (observed)
The Inspectors evaluated the licensees boric acid corrosion control program performance.
71111.11A - Licensed Operator Requalification Program and Licensed Operator Performance
Requalification Examination Results (IP Section 03.03) (1 Sample)
- (1) The licensee completed the annual requalification operating examinations required to be administered to all licensed operators in accordance with Title 10 of the Code of Federal Regulations 55.59(a)(2), "Requalification Requirements," of the NRC's "Operator's Licenses." During the week of December 5, 2022, the inspector performed an in-office review of the overall pass/fail results of the individual operating examinations and the crew simulator operating examinations in accordance with Inspection Procedure (IP) 71111.11, "Licensed Operator Requalification Program." These results were compared to the thresholds established in Section 3.03, "Requalification Examination Results," of IP 71111.11.
The inspectors reviewed and evaluated the licensed operator examination failure rates for the requalification annual operating and biennial written exams completed on October 7, 2022.
71111.11B - Licensed Operator Requalification Program and Licensed Operator Performance
Licensed Operator Requalification Program (IP Section 03.04) (1 Sample)
- (1) Biennial Requalification Written Examinations The inspectors evaluated the quality of the licensed operator biennial requalification written examination administered during September and October 2022.
Annual Requalification Operating Tests The inspectors evaluated the adequacy of the facility licensees annual requalification operating test.
Administration of an Annual Requalification Operating Test The inspectors evaluated the effectiveness of the facility licensee in administering requalification operating tests required by 10 CFR 55.59(a)(2) and that the facility licensee is effectively evaluating their licensed operators for mastery of training objectives.
Requalification Examination Security The inspectors evaluated the ability of the facility licensee to safeguard examination material, such that the examination is not compromised.
Remedial Training and Re-examinations The inspectors evaluated the effectiveness of remedial training conducted by the licensee, and reviewed the adequacy of re-examinations for licensed operators who did not pass a required requalification examination.
Operator License Conditions The inspectors evaluated the licensees program for ensuring that licensed operators meet the conditions of their licenses.
Control Room Simulator The inspectors evaluated the adequacy of the facility licensees control room simulator in modeling the actual plant, and for meeting the requirements contained in 10 CFR 55.46.
Problem Identification and Resolution The inspectors evaluated the licensees ability to identify and resolve problems associated with licensed operator performance.
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 main control room during shutdown and cooldown for U1R25 on October 21-22, 2022.
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed and evaluated just in time training in the simulator on new main feedwater pump control system on November 8, 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:
July 18, 2022 Quality Control (IP Section 03.02) (1 Sample)
The inspectors evaluated the effectiveness of maintenance and quality control activities to ensure the following SSC remains capable of performing its intended function:
- (1) Installation of temporary T-piece and blind flange in place of failed excess letdown divert valve on November 19, 2022
71111.13 - Maintenance Risk Assessments and Emergent Work Control
Risk Assessment and Management Sample (IP Section 03.01) (3 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, Yellow shutdown risk week of October 23-29, 2022, including emergent inoperability of 1B EDG and while RCS level was below Rx flange level for reactor disassembly, including review of defense in depth protected equipment for U1R25.
- (2) Unit 1, Yellow shutdown risk November 11, 2022, with RCS level below Rx flange level for reactor head installation, including review of defense-in-depth assessment and protected equipment for U1R25.
- (3) Unit 1 and 2, the week of November 19 - November 23, including Unit 1 Yellow shutdown risk and unit transition from Mode 5 to Mode 2
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (8 Samples)
The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:
- (1) Past Operability Evaluation (POE) for the 2B shutdown board with the A- and C-phase overcurrent relays removed from the 2B containment spray pump breaker on July 1, 2022.
- (2) POE on turbine stop valve #2 failed to close during manual turbine trip on October 22, 2022
- (4) Acceptance criterion for 1-VLV-62-504 not met during 1B charging pump as found test on October 30, 2022
- (5) Blown fuses in auxiliary relay racks for trip of Unit 2 RCPs on underfrequency on November 1, 2022
- (6) As left local leak rate test (LLRT) on 1-FCV-70-85 leakage exceeds acceptance criteria on November 8, 2022
- (7) Unit 1 main steam safety valve 1-523 set leakage on November 22, 2022
- (8) Unit 1 SR 3.3.1.3 Nuclear Instruments Axial Imbalance acceptance criteria exceeded on November 28, 2022
71111.18 - Plant Modifications
Severe Accident Management Guidelines (SAMG) Update (IP Section 03.03) (1 Sample)
- (1) The inspectors verified the site Severe Accident Management Guidelines were updated in accordance with the Pressurized-Water Reactor Owners Group generic severe accident technical guidelines and validated in accordance with NEI 14-01, Emergency Response Procedures and Guidelines for Beyond Design Basis Events and Severe Accidents, Revision 1 on October 4, 2022.
71111.19 - Post-Maintenance Testing
Post-Maintenance Test Sample (IP Section 03.01) (10 Samples)
The inspectors evaluated the following post-maintenance testing activities to verify system operability and/or functionality:
- (1) Work order (WO) 123056969, 1-VLV-62-548, Seal Water Injection Filter Isolation Valve packing follower is split, perform temporary leak repair on October 5, 2022
- (2) WO 123261341, Replace 1B2 EDG engine driven fuel oil pump due to seal leakage on October 25, 2022
- (3) WO 123274399, Replace 1 pipe at 1A RHR pump casing drain line due to leak on November 6, 2022
- (4) WO 117809388, Replace component cooling water system (CCS) pump motor 1A-A on November 7,2022
- (5) WO 123077173, Replace 1B-B centrifugal charging pump (CCP) element on November 10, 2022
- (6) WO 123277402, Install temporary T-piece and blind flange in place of failed excess letdown divert valve (TMOD SQN-1-2022-062-03) on Nov 11, 2022
- (7) WO 123288758, 1-VLV-62-576 (Pen X-43D CIV) failed to close during RT shot, replace valve on November 12, 2022
- (8) WO 122555964, Change oil and collect samples from inboard and outboard bearings on Containment Spray Pump 2A on November 15, 2022
- (9) WO 122075045, Replace SIS loop 4 hot leg 6 inch primary check valve due to gross leakage on November 21, 2022
- (10) WO 122704769, 2-SI-SXP-003-201.S TDAFW Pump 2A-S XI Test following leakage deflector install WO 121325993 on December 27, 2022
71111.20 - Refueling and Other Outage Activities
Refueling/Other Outage Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated refueling outage 1R25 activities from October 21 - November 23, 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) (4 Samples)
- (1) 1-SI-OPS-082-026.A, Loss of Offsite Power with Safety Injection, D/G 1A-A Test, on October 23, 2022
- (2) 1-SI-SLT-088-156.0, U1 Containment Integrated Leak Rate Test on November 16, 2022
- (3) 1-SI-SXV-063-204.0, Safety Injection/Residual Heat Removal Hot Leg Primary Check Valve Integrity Test on November 21, 2022
- (4) 1-SI-SXI-068-201.0, Leakage Test of the Reactor Coolant Pressure Boundary on
November 22, 2022 Inservice Testing (IP Section 03.01) (2 Samples)
- (1) 1-SI-SXP-062-203.0, Centrifugal Charging Pumps 1A-A and 1B-B Comprehensive Pump Test and Check Valve Test on October 30, 2022
- (2) 1-SI-SXP-063-202.0, Safety Injection Pump 1A-A Comprehensive Performance and Check Valve Test on November 9, 2022
Containment Isolation Valve Testing (IP Section 03.01) (1 Sample)
- (1) 0-SI-SLT-070-258.1, CCS from Excess Letdown HX CIV Local Leak Rate Test and valve stroke on November 7, 2022
Ice Condenser Testing (IP Section 03.01) (1 Sample)
- (1) 0-SI-MIN-061-105.0 Ice Condenser - Ice Weighing on November 9,
RADIATION SAFETY
71124.01 - Radiological Hazard Assessment and Exposure Controls
Radiological Hazard Assessment (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated how the licensee identifies the magnitude and extent of radiation levels and the concentrations and quantities of radioactive materials and how the licensee assesses radiological hazards.
Instructions to Workers (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated how the licensee instructs workers on plant-related radiological hazards and the radiation protection requirements intended to protect workers from those hazards.
Contamination and Radioactive Material Control (IP Section 03.03) (3 Samples)
The inspectors observed/evaluated the following licensee processes for monitoring and controlling contamination and radioactive material:
- (1) Licensee surveys of potentially contaminated material leaving the radiologically controlled area (RCA) during Unit 1 refueling outage 25 (U1R25).
- (2) Workers exiting the RCA during U1R25.
- (3) Workers exiting Unit 1 containment during U1R25.
Radiological Hazards Control and Work Coverage (IP Section 03.04) (3 Samples)
The inspectors evaluated the licensee's control of radiological hazards for the following radiological work:
- (2) AP 2022-140, U1R25 Replace Check Valve 63-558.
- (3) AP 2022-111, U1R25 Reactor Disassembly and Reassembly.
High Radiation Area and Very High Radiation Area Controls (IP Section 03.05) (2 Samples)
The inspectors evaluated licensee controls of the following High Radiation Areas and Very High Radiation Areas:
- (1) Unit 1 Lower Containment
- (2) Unit 1 Cavity Drain Line Radiation Worker Performance and Radiation Protection Technician Proficiency (IP Section 03.06) (1 Sample)
- (1) The inspectors evaluated radiation worker and radiation protection technician performance as it pertains to radiation protection requirements.
71124.03 - In-Plant Airborne Radioactivity Control and Mitigation
Permanent Ventilation Systems (IP Section 03.01) (1 Sample)
The inspectors evaluated the configuration of the following permanently installed ventilation systems:
- (1) Control Room Emergency Ventilation System.
Temporary Ventilation Systems (IP Section 03.02) (1 Sample)
The inspectors evaluated the configuration of the following temporary ventilation systems:
- (1) Portable high efficiency particulate air (HEPA) unit no. 700-04.
Use of Respiratory Protection Devices (IP Section 03.03) (1 Sample)
- (1) The inspectors evaluated the licensees use of respiratory protection devices.
Self-Contained Breathing Apparatus for Emergency Use (IP Section 03.04) (1 Sample)
- (1) The inspectors evaluated the licensees use and maintenance of self-contained breathing apparatuses.
71124.04 - Occupational Dose Assessment
Source Term Characterization (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated licensee performance as it pertains to radioactive source term characterization.
External Dosimetry (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated how the licensee processes, stores, and uses external dosimetry.
Special Dosimetric Situations (IP Section 03.04) (3 Samples)
The inspectors evaluated the following special dosimetric situations:
- (1) Neutron dose assignment for dry cask welding.
- (2) Shallow dose equivalent noble gas dose assignment for pressurizer manway removal.
- (3) Declared pregnant worker.
71124.05 - Radiation Monitoring Instrumentation
Walkdowns and Observations (IP Section 03.01) (8 Samples)
The inspectors evaluated the following radiation detection instrumentation during plant walkdowns:
- (1) Area radiation monitors in the auxiliary building
- (2) Continuous air monitors in the auxiliary building
- (3) Portal monitors at the RCA exit point
- (4) Personnel contamination monitors at the RCA exit point
- (5) Small article monitors at the RCA exit point
- (6) Portable ion chamber survey meters stored ready for use
- (7) Portable neutron survey meters stored ready for use
- (8) Portable telescoping survey meters stored ready for use
Calibration and Testing Program (IP Section 03.02) (12 Samples)
The inspectors evaluated the calibration and testing of the following radiation detection instruments:
- (1) Ludlum 9-3 ion chambers, ID numbers 860870 and 860849
- (2) Mirion Telepole II, ID number 951942
- (3) Ludlum Model 12-4 REM Ball, ID number 951382
- (4) Ortec high-purity germanium detectors, ID numbers 1 and 2
- (5) Canberra GEM-5, ID number 0909-180
- (6) Canberra Chronos, ID number 951682
- (7) Canberra Argos, ID number 806588
- (8) Ortec Standfast II, ID number SQN02
- (9) U2 Containment High Range Area Monitor, 2-RE-90-271
- (10) U2 Containment High Range Area Monitor, 2-RE-90-274
- (11) Eberline AMS-4, ID number 860272
- (12) Hopewell Designs WI90 well irradiator, 2022 validation testing results Effluent Monitoring Calibration and Testing Program Sample (IP Sample 03.03) (3 Samples)
The inspectors evaluated the calibration and maintenance of the following radioactive effluent monitoring and measurement instrumentation:
- (1) Unit 2 shield building vent monitor, low, mid, high range, 2-RE-90-400A, B, and C
- (2) Unit 2 shield building vent monitor, accident range ion chamber, 2-RE-90-261
- (3) Liquid Waste Monitor, 0-RE-90-122
71124.07 - Radiological Environmental Monitoring Program
Environmental Monitoring Equipment and Sampling (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated environmental monitoring equipment and observed collection of environmental samples.
Radiological Environmental Monitoring Program (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated the implementation of the licensees radiological environmental monitoring program.
GPI Implementation (IP Section 03.03) (1 Sample)
- (1) The inspectors evaluated the licensees implementation of the Groundwater Protection Initiative program to identify incomplete or discontinued program elements.
OTHER ACTIVITIES - BASELINE
===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
OR01: Occupational Exposure Control Effectiveness Sample (IP Section 02.15) ===
- (1) October 9, 2021 through October 6, 2022 PR01: Radiological Effluent Technical Specifications/Offsite Dose Calculation Manual Radiological Effluent Occurrences (RETS/ODCM) Radiological Effluent Occurrences Sample (IP Section 02.16) (1 Sample)
- (1) July 17, 2021 through September 14, 2022
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 in equipment reliability that might be indicative of a more significant safety issue.
71153 - Follow Up of Events and Notices of Enforcement Discretion Event Report (IP Section 03.02)
The inspectors evaluated the following licensee event reports (LERs):
- (1) LER 05000327/2022-001-00, Failure of 1B-B Centrifugal Charging Pump Results in Condition Prohibited by Technical Specifications (ML22258A065). The inspectors determined that it was not reasonable to foresee or correct the cause discussed in the LER; therefore, there was no performance deficiency associated with the technical specification violation for which the NRC granted enforcement discretion (NOED EA-2022-072). The related Unresolved Issue (URI 05000327/2022003-01, 1B-B centrifugal charging pump (CCP) unable to maintain Pressurizer Level at power)is also closed and documented in this report under Inspection Results Section.
Notice of Enforcement Discretion (NOED) (IP Section 03.04) (1 Sample)
- (1) The inspectors evaluated the licensee actions surrounding NOED EA-2022-072 which can be accessed at http://www.nrc.gov/reading-rm/doc-collections/enforcement/notices/noedreactor.html, on July 21, 2022. The inspectors completed inspection procedure Sections 03.04.c and 03.04.d. The inspectors documented the completion of inspection procedure Sections 03.04.a and 03.04.b in Sequoyah Nuclear Plant, Units 1 and 2 - Integrated Inspection Report
===05000327/2022003 and 05000328/2022003 (ML22307A038).
OTHER ACTIVITIES
- TEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL 92702 - Follow-Up on Traditional Enforcement Actions Including Violations, Deviations, Confirmatory Action Letters, and Orders The purpose of this follow-up inspection is to ascertain whether the actions taken by the licensee address the commitments of the 2017 Confirmatory Order (CO). The Regional Administrator has authorized staff to use IP 92702, Follow-Up on Traditional Enforcement Actions Including Violations, Deviations, Confirmatory Action Letters, and Orders, to perform follow-up inspections of the 2017 Confirmatory Order (CO) at Tennessee Valley Authority (TVA)
Corporate, Browns Ferry, Sequoyah and Watts Bar because these follow-up inspections are not part of the reactor oversight program (ROP) baseline inspections. On November 15, the inspectors completed the inspections of the following 2017 CO items:
Follow-Up on Traditional Enforcement Actions Including Violations, Deviations, Confirmatory Action Letters, and Orders ===
- (1) Commitment V.1.c.3: The inspectors reviewed the conducted in-person benchmarks of the adverse employee action/employee review board process at Wolf Creek during the week of June 25, 2019, and at Diablo Canyon during the week of November 23, 2019. TVA also conducted in-person benchmarking during the week of February 3, 2020, at Oak Ridge and another in-person benchmark was conducted on February 27, 2020. The inspectors determined that the results of the benchmark reports were documented in CRs 1612054, 1529234, 1612145, and 1612770. Benchmarks conducted were completed within the three-year period as required by the 2017 CO. The inspectors determined that TVA has fulfilled this CO action item for TVA Corporate, Browns Ferry, Sequoyah and Watts Bar.
- (2) Commitment V.1.d.1: The inspectors reviewed the following independent third-party audits:
1. 1st Quarterly Audit completed 09/30/2017 2. 2nd Quarterly Audit completed 12/21/2017 3. 3rd Quarterly Audit completed 04/09/2018 4. 4th Quarterly Audit completed 7/10/2018 5. 1st Semi-Annual Audit completed 12/28/2018 6. 2nd Semi-Annual Audit completed 06/27/2019 7. 3rd Semi-Annual Audit completed 12/26/2019 8. 4th Semi-Annual Audit completed 06/26/2020 The inspectors determined that the third-party chosen to audit the adverse action process was independent of TVA and had no direct or previous involvement with implementation of the adverse employment action process at TVA. These audit reports were to:
1. Evaluate whether the TVA is in compliance with its Adverse Employee Action process 2. Review all adverse employee actions
3. Periodically attend Executive Review Board (ERB) meetings
4. Review Chilling Effect mitigation plans 5. Evaluate whether the process is effective at:
a. Determining whether adverse employment actions comport with employee protection regulations, b. Whether adverse employment actions could negatively impact the SCWE c. Developing plans to mitigate the potential chilling effects of adverse employment actions 6. Report all findings and recommendations of the audits to the Chief Nuclear Officer (CNO)
The inspectors determined that TVA has fulfilled this CO action item for TVA Corporate, Browns Ferry, Sequoyah and Watts Bar.
- (3) Commitment V.1.e.1: The inspectors reviewed the independent safety culture assessments performed by TVA and determined that they were complete and provided a thorough evaluation of the safety culture at the TVA sites. The methodology used to perform the assessments met the criteria for being independent and used appropriate social science research methods and statistical analysis to determine the strengths and weaknesses in the safety culture traits at each site. The team also reviewed the corrective actions and determined that they were appropriate for addressing the issues identified in the assessments. The inspectors determined that TVA has fulfilled this CO action item for TVA Corporate, Browns Ferry, Sequoyah and Watts Bar.
- (4) Commitment V.1.f.1.c: The inspectors reviewed CR-1271309 which documented the root cause that identified CC-03, Holistic framework for managing Confirmatory Orders does not exist at TVA. In response to CC-03, CR 1271309 included seven corrective actions. The inspectors reviewed the corrective actions associated with this Order item and determined that they are comprehensive and are being completed in a timely manner. The inspectors determined that TVA has fulfilled this CO action item for TVA Corporate, Browns Ferry, Sequoyah and Watts Bar.
- (5) Commitment V.1.f.2: The inspectors reviewed the TVAs submittal letter to NRC on October 5, 2022 (ML# 22278A083), to provide the basis for concluding that the CO has been satisfied. TVA entered the Confirmatory Order actions into the corrective action program and completed the associated Condition Report (CR) actions. The inspectors reviewed the letter and TVAs corrective actions and determined that TVA has fulfilled this CO action item for TVA Corporate, Browns Ferry, Sequoyah and Watts Bar.
INSPECTION RESULTS
Unauthorized entry into a High Radiation Area Cornerstone Significance Cross-Cutting Report Aspect Section Occupational Green [H.12] - Avoid 71124.01 Radiation Safety NCV 05000327,05000328/2022004-01 Complacency Open/Closed A self-revealing, Green, Non-cited Violation (NCV) of Technical Specification (TS) 5.7.1 was identified for a worker who improperly entered a posted high radiation area (HRA).
Specifically, the worker entered the HRA without being logged onto an appropriate radiation work permit (RWP) and without being knowledgeable of dose rates in the area prior to entry.
Description:
On November 9, 2022, an individual was performing work in support of Unit 1 refueling outage 25 (U1R25) cavity drain-down and reactor head lift activities in upper containment. The worker was logged onto RWP 22140001 which did not allow access into posted HRAs and had self-reading dosimeter (SRD) alarm setpoints of 31 mrem and 71 mrem/hr. While attempting to communicate with a scaffolding work crew, the individual entered a newly-created HRA boundary that was established near the cavity railing for expected increased radiological conditions at the completion of cavity drain-down. Upon approaching the cavity railing to look down into the cavity, the worker received a SRD dose rate alarm of 150 mrem/hr. After receiving the dose rate alarm the worker exited the HRA and reported to radiation protection (RP).
Corrective Actions: The licensee's follow-up actions included entering this event into their corrective action program, excluding the individual from the radiologically controlled area pending investigation, conducting a plant stand down during shift turnover to review the event, and stationing an RP technician at the upper containment reactor cavity HRA boundary.
Corrective Action References: Condition Report 1816036
Performance Assessment:
Performance Deficiency: The failure to use an appropriate RWP and to receive a briefing on current radiological conditions prior to entering a HRA , as required by TS 5.7.1, was a performance deficiency.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Human Performance attribute of the Occupational Radiation Safety cornerstone and adversely affected the cornerstone objective to ensure the adequate protection of the worker health and safety from exposure to radiation from radioactive material during routine civilian nuclear reactor operation. Specifically, workers who enter HRAs without authorization and encounter dose rates exceeding 100 mrem/hr, could receive unplanned exposure.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix C, Occupational Radiation Safety SDP. The finding was determined to be of very low safety significance (Green) because it was not related to ALARA planning, did not result in an overexposure, there was no substantial potential for overexposure, and the ability to assess dose was not compromised.
Cross-Cutting Aspect: H.12 - Avoid Complacency: Individuals recognize and plan for the possibility of mistakes, latent issues, and inherent risk, even while expecting successful outcomes. Individuals implement appropriate error reduction tools. Specifically, the worker did not stop and use appropriate human error reduction tools prior to proceeding past a HRA boundary.
Enforcement:
Violation: Technical Specification 5.7.1 requires that access to each HRA shall be controlled by means of an RWP and that workers be knowledgeable of dose rates in the area prior to entry. Contrary to this, on November 9, 2022, a worker entered a HRA around the U1 reactor cavity without being logged onto an appropriate RWP and without being knowledgeable of dose rates in the area prior to entry.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Licensee-Identified Non-Cited Violation 71124.07 This violation of very low safety significance was identified by the licensee and has been entered into the licensee corrective action program and is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Violation: Technical Specification 5.4.1 requires that the procedures recommended by Regulatory Guide 1.33 be established, implemented, and maintained, including procedures for meteorological monitoring. Licensee procedure EPFS-3, "Servicing of Meteorological Equipment at Environmental Data Stations", revision 20, requires that the inspection, servicing and maintenance program for meteorological instrumentation ensures an annual joint data recovery for atmospheric stability, wind speed, and wind direction of at least 90%. Contrary to this, for calendar year 2021, the annual joint data recovery for atmospheric stability, wind speed, and wind direction ranged from 22% to 70%.
Significance/Severity: Green. This Finding in the area of environmental monitoring was determined to have Green significance using the Public Radiation Safety Significance Determination Process.
Corrective Action References: CR 1731719, CR 1742782 URI 1B-B centrifugal charging pump (CCP) unable to maintain 71153 Pressurizer Level at power URI 05000327/2022003-01
Description:
On July 18, 2022, operators noted the 1B-B centrifugal charging pump (CCP)was unable to maintain pressurizer level with downstream charging flow control valve (1-PCV-62-93) full open. Operators placed the 1A-A CCP in service and pressurizer level began to recover and maintained level normally. On July 18, 2022, at 22:30 Eastern Daylight Time (EDT), operators declared the 1B-B CCP inoperable and entered Technical Specification limiting condition for operation (LCO) 3.5.2, Emergency Core Cooling Systems (ECCS)required action A for one train of ECCS inoperable. During troubleshooting activities, the licensee determined the direct cause of the 1B-B CCP degradation was most likely pump element wear associated with cyclic fatigue. Repair activities required replacing the pump element. This repair activity was forecast to extend beyond the original Technical Specification 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed outage time.
On July 21, 2022, at 17:30 EDT, the licensee requested that a Notice of Enforcement Discretion (NOED) be issued. The licensee requested the NOED be effective for 69 hours7.986111e-4 days <br />0.0192 hours <br />1.140873e-4 weeks <br />2.62545e-5 months <br /> past the TS LCO 3.5.2, Action A expiration, i.e., until 19:30 EDT on Sunday, July 24, 2022. The licensee exited from Technical Specification LCO 3.5.2, Action A at 16:35 EDT on July 24, 2022. As a result, the NOED terminated at 16:35 EDT on July 24, 2022, within the period of the enforcement discretion.
The inspectors performed an assessment of the adequacy of the licensee corrective actions and cause determinations and evaluated whether the cause for NOED request was the result of a violation or a failure to meet a licensee self-imposed standard.
After removal of the pump internals, disassembly of the internals was performed at the pump vender facility. The pump showed heavy wear in impellers stages 11-6 on 180 degrees of the impeller wear rings, which is consistent with shaft bow. A shaft crack was identified at the 11th stage impeller, split ring keeper key. This allowed for the shaft to bow during operation and cause wear damage to the internals.
The pump shaft cracked because of low stress, high cycle fatigue, due to continuous operation at low flow conditions. Numerous similar events of CCP failures occurred during the 1990s. Several upgrades have been made to improve this type of pump, the last major change being a shaft material upgrade to CA625 material. This pump was refurbished in 2001 with the upgraded CA625 shaft. It had 100,441 hours0.0051 days <br />0.123 hours <br />7.291667e-4 weeks <br />1.678005e-4 months <br /> of operation when it failed. This is the first low stress, high fatigue failure for a CA625 material shaft and indicates that while the shaft is stronger and lasts much longer, it still has a time limitation.
The licensees corrective action is to implement periodic refurbishments to replace the shaft.
The 1B-B CCP failed at 100441 hours (11.5 years) of operation over a 21-year period. The licensee is implementing an eleven refueling outage refurbishment window. This accommodates a potential deferral of one cycle and still being under 100000 operating hours.
Based on the circumstances surrounding the failure of the pump, the inspectors determined that this issue was not reasonably within the licensees ability to foresee and prevent; therefore, there was no performance deficiency associated with this technical specification violation for which the NRC granted enforcement discretion.
This inspection closes URI 05000327/2022003-01, "1B-B centrifugal charging pump (CCP)unable to maintain Pressurizer Level at power" and LER 05000327/2022-001-00, "Failure of 1B-B Centrifugal Charging Pump Results in Condition Prohibited by Technical Specifications."
Corrective Action Reference(s): CR 1790511,CR 1792274, WO 123048176, WO
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
On January 30, 2023, the inspectors presented the integrated inspection results to Thomas Marshall and other members of the licensee staff.
On October 6, 2022, the inspectors presented the Licensed Operator Requalification Program inspection results to Gary Garner - SQN Training Director and other members of the licensee staff.
On November 15, 2022, the inspectors presented the Follow-up of the 2017 Confirmatory Order inspection results to Bob Duncan, Senior VP of Engineering and Ops Support and other members of the licensee staff.
On November 22, 2022, the inspectors presented the Radiation Protection inspection exit meeting inspection results to T Marshall and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection Type Designation Description or Title Revision or
Procedure Date
71111.04 Procedures 0-SI-OPS-082- Diesel Generator Operability Verification Revision 22
007.0
0-SO-74-1 Residual Heat Removal System Revision 112
0-SO-82-1 Diesel Generator 1A-A Revision 64
1-PI-OPS-000- Operator At The Controls Duty Station Checklists Modes 1-4 Revision 80
20.1
1-SI-OPS-063- 1B-B SI Pump Casing, Suction, And Discharge Piping Vent Revision 33
29.B
1-SO-3-2 Auxiliary Feedwater System, Attachment 3, Standby Revision 62
Readiness Checklist
1-SO-63-5, ATT 2 Emergency Core Cooling System Valve Checklist 09/07/2021
71111.05 Fire Plans AUX-0-669-01 Pre-Fire Plan Auxiliary Building elevation 669 Unit 1 Side Revision 8
AUX-0-669-02 Pre-Fire Plan Auxiliary Building elevation 669 Unit 2 Side Revision 13
AUX-0-669-03 Pre-Fire Plan Auxiliary Building elevation 669 Common Area Revision 8
RXB-0-679-01 Pre-Fire Plan Reactor Building elevation 679 Revision 3
RXB-0-701-0 Pre-Fire Plan Reactor Building Annulus Revision 3
RXB-0-734-01 Pre-Fire Plan Reactor Building elevation 734 Revision 3
71111.12 Corrective Action CR 1790511 1B CCP degraded flow 07/19/2022
Documents CR 1790981 Revise CCP quarterly performance test 07/20/2022
Miscellaneous PO 00002071 Tee, Pipe, Q level: QA1 ASME sec III class 2 03/13/2003
PO 2571723 Flange, pipe QA 1, socket weld 12/07/2015
Work Orders 123048063 SBE to troubleshoot 1B CCP degraded flow 07/19/2022
WO 123277402 Install temporary T-piece (TMOD SQN-1-2022-062-03) 11/11/2022
71111.13 Corrective Action CR 1811970 1B EDG Roll/253 DID availability 10/25/2022
Documents CR 1811976 Negative trend in application of defense in depth 10/25/2022
requirements
Procedures 1-PI-OPS-000- SQN Defense-in-Depth Assessment Revision 42
20.2
71111.15 Corrective Action CR 1811241 Turbine Stop Valve #2 failed to indicate closed on 1-XX-55- 10/22/2022
Documents 6A and locally
CR 1812514 1A-A RHR pump has leakage that appears to be from 10/28/2022
Inspection Type Designation Description or Title Revision or
Procedure Date
shaft/seal
CR 1813130 RHR 1A Vibration Step Change 10/27/2022
CR 1813385 Acceptance criterion for 1-VLV-062-504 not met during 1B 10/30/2022
CCP as found test
CR 1813810 Blown fuses in auxiliary relay room for underfrequency RCP 11/01/2022
trip
CR 1813935 RHR Drain Line Vibration 11/01/2022
CR 1819673 U1 axial imbalance comparison acceptance criteria 11/28/2022
exceeded
Engineering Evaluation SQN- Engineering Evaluation for impact of failed SQN-1-FCV-070- 11/19/2022
Evaluations 1-FCV-070-085 085 LLRT on overall containment acceptance criteria in 0-SI-
SLT-000-160.0.
Operability CAR 1811241 Past Operability Evaluation for Turbine Stop Valve #2 fail to 10/28/2022
Evaluations close
71111.19 Corrective Action CR 1814962 1B CCP had high vibrations on inboard pump bearing 11/6/2022
Documents horizontal direction
CR 1815316 1B CCP coupling was found to not be meeting design criteria 11/7/2022
Corrective Action CR 1820533 NRC Identified: PMT insufficient for 1-VLV-062-0576 12/1/2022
Documents
Resulting from
Inspection
Procedures 0-SI-OPS-082- Diesel Generator Operability Verification Revision 22
007.0
0-SI-SXI-000- ASME Section XI Inservice Pressure Test Revision 25
201.0
1-SI-SXI-068- Leakage Test of the Reactor Coolant Pressure Boundary Revision 17
201.0
1-SI-SXP-062- Centrifugal Charging Pump 1A-A and 1B-B Comprehensive Revision 19
203.0 Pump Test and Check Valve Test
1-SI-SXP-070- Component Cooling Pump 1A-A Performance Test Revision 15
201.A
1-SI-SXV-063- Safety Injection/Residual Heat Removal Hot Leg Primary Revision 15
204.0 Check Valve Integrity Test
2-SI-SXP-003- TDAFW Pump 2A-S XI Test Revision35
Inspection Type Designation Description or Title Revision or
Procedure Date
201.S
2-SI-SXP-072- Containment Spray Pump 2A-A Performance Test Revision 15
201.A
Work Orders SQN-1-BCTA- Replace HFA relays 1X, 30X, and 30RX, Attachment B Post 02/07/2022
003-0128-A, PM Maintenance Test
20939
71111.22 Corrective Action CR 1815363 As left LLRT on 1-FCV-70-85 leakage exceeds acceptance 11/8/2022
Documents criteria
CR 1818802 1-VLV-63-641 and 644 cannot be tested due to boundary 11/22/2022
valve leakage
Corrective Action CR 1812514 1A-A RHR pump has leakage that appears to be from 10/26/2022
Documents shaft/seal
Resulting from
Inspection
Procedures 0-SI-SLT-000- Primary Containment Total Leak Rate Revision 13
160.0
0-SI-SLT-070- Containment Isolation Valve LLRT Component Cooling, Revision 19
258.1 Attachment 1, Penetration X-35/53
1-SI-SLT-088- U1 Containment Integrated Leak Rate Test Revision 9
156.0
1-SI-SXP-063- Safety Injection Pumps 1A-A and 1B-B Comprehensive Revision 12
2.0 Performance and Check Valve Test
Work Orders WO 123186394 1B Charging Pump comprehensive test (initial performance 10/30/2022
following July 2022 code relief for pump replacement)
71124.01 Corrective Action CR 1731686
Documents CR 1816036
Radiation SQN-M- Uppost from RA to HRA Post drain down 11/09/2022
Surveys 20221110-7
Radiation Work 221400001 Movement of spent fuel in the reactor cavity Rev 0
Permits (RWPs)
71124.05 Corrective Action CR 1814304
Documents
Resulting from
Inspection
Inspection Type Designation Description or Title Revision or
Procedure Date
Procedures RCI-05.301 Operational Checks for the GEM-5 Portal Monitor Revision 12
71124.07 Corrective Action CR 1665658
Documents CR 1729681
CR 1731719
CR 1742782
CR 1744493
Miscellaneous SQN Meteorological Data Recovery Table 2021 Annual
Procedures 0-TI-CEM-999- Collection of Radiological Environmental Monitoring Samples Revision
000 0002
EPFS-3 Servicing of Meteorological Equipment at Environmental Revision 20
Data Stations
71151 Corrective Action CR 1783230
Documents
71152S Corrective Action CR 1791006 Trend in IST surveillances not being transmitted within 31 07/20/2022
Documents days as required by NPG-SPP-6.9.2.
CR 1791206 Negative trend in Safety Related Pump Performance 07/21/2022
CR 1802742 Sequoyah has missed opportunities to explore behavior 09/15/2022
contributors to equipment challenges
Self-Assessments 2022 SQN Mid-Cycle Self Assessment 09/07/2022
71153 Corrective Action CR 1790511 1B CCP Degraded Flow 07/19/2022
Documents
Engineering RT-LTR-22-68 Failure Examination of Cracked CCP Shaft from Sequoyah Revision 0
Evaluations Unit 1
2702 Corrective Action CR 1404011 Sequoyah response to ORAU Report
Documents CR 1416534 Track Corporate's response to NSC assessment.
CR 1557934 Nuclear Safety Culture Survey
CR 1565109 Corporate Nuclear Safety Culture Survey
CR 1612054 Benchmarking Report - PG&E Diablo Canyon Adverse 12/21/2019
Employment Action Process
CR 1612770 Benchmarking Report - Oak Ridge Disciplinary / Adverse 4/28/2020
Employment Action Process
CR1529234 Benchmarking Report - Benchmark of Wolf Creek Station 11/12/2019
Adverse Employment Action Process November 12, 2019
Inspection Type Designation Description or Title Revision or
Procedure Date
Miscellaneous Corporate Office
Complex
Independent
Nuclear Safety
Culture
Assessment,
FY2020
Sequoyah
Nuclear Plant
Independent
Nuclear Safety
Culture
Assessment
FY2020
Procedures NPG-SPP-01.7.4 Adverse Employment Action and the Executive Review Rev. 0008
Board
2