IR 05000327/2020003
| ML20315A312 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 11/10/2020 |
| From: | Tom Stephen NRC/RGN-II |
| To: | Jim Barstow Tennessee Valley Authority |
| References | |
| IR 2020002 | |
| Download: ML20315A312 (25) | |
Text
November 10, 2020
SUBJECT:
SEQUOYAH, UNITS 1 AND 2 - INTEGRATED INSPECTION REPORT 05000327/2020003, 05000328/2020003 AND 07200034/2020002
Dear Mr. Barstow:
On September 30, 2020, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Sequoyah, Units 1 and 2. On October 26, 2020, the NRC inspectors discussed the results of this inspection with Mr. Scott Hunnewell 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.
If you contest the violation or the significance or severity of the violation 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. 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,
/RA/
Thomas A. Stephen, Chief Reactor Projects Branch #5 Division of Reactor Projects
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:
05000327/2020003, 05000328/2020003 and 07200034/2020002
Enterprise Identifier: I-2020-003-0060 and I-2020-002-0083
Licensee:
Tennessee Valley Authority
Facility:
Sequoyah, Units 1 and 2
Location:
Soddy Daisy, TN 37379
Inspection Dates:
July 01, 2020 to September 30, 2020
Inspectors:
N. Childs, Resident Inspector
B. Collins, Senior Reactor Inspector
J. Diaz-Velez, Senior Health Physicist
S. Downey, Senior Reactor Inspector
D. Hardage, Senior Resident Inspector
A. Nielsen, Senior Health Physicist
J. Rivera, Health Physicist
Approved By:
Thomas A. Stephen, 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
Failure to Establish Adequate FME Controls Results in Inoperable Reactor Vessel Level Indication System (RVLIS)
Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000328/2020003-01 Open/Closed
[H.1] -
Resources 71152 A self-revealing green NCV of 10 CFR 50 Appendix B, Criterion V, Instructions, Procedures, and Drawings, was identified when the licensee failed to establish appropriate foreign material exclusion (FME controls associated with installation of reactor vessel level instrumentation system (RVLIS) equipment, an activity affecting quality. Specifically, the foreign material exclusion FME controls prescribed in maintenance procedure 0-MI-MRR-068-006.0, "Installation of Reactor Pressure Vessel Head and Attachments," failed to provide adequate guidance and resulted in blockage and subsequent inoperability of the upper pressure channels of the reactor vessel level instrumentation system (RVLIS).
Additional Tracking Items
Type Issue Number Title Report Section Status LER 05000327/2020-002-00 LER 2020-002-00 for Sequoyah Nuclear Plant,
Unit 1, Safety Injection Signal with Reactor Trip Caused by a Failure with the Main Turbine Control System 71153 Closed LER 05000327/2019-003-01 LER 2019-03-001 for Sequoyah Nuclear Plant,
Unit 1, Automatic Reactor Trip due to Negative Rate Trip as a Result of a Dropped Control Rod 71153 Closed
PLANT STATUS
Unit 1 began the inspection period at 100 percent rated thermal power (RTP). On July 22, 2020, operators reduced power to 94 percent RTP following the trip of the #1 oil pump on A main feedwater pump. On July 31, 2020, power was reduced to 45 percent RTP and the A main feedwater pump was removed from service to replace the #1 oil pump. The unit was returned to 100 percent RTP on August 2, 2020 and remained at or near 100 percent RTP for the remainder of the inspection period.
Unit 2 operated at or near 100 percent 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 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. Starting on March 20, 2020, in response to the National Emergency declared by the President of the United States on the public health risks of the coronavirus (COVID-19), resident and regional inspectors were directed to begin telework and to remotely access licensee information using available technology. During this time the resident inspectors performed periodic site visits each week, increasing the amount of time on site as local COVID-19 conditions permitted. As part of their onsite activities, resident inspectors conducted plant status activities as described in IMC 2515, Appendix D; observed risk significant activities; and completed on site portions of IPs. In addition, resident and regional baseline inspections were evaluated to determine if all or portion of the objectives and requirements stated in the IP could be performed remotely. If the inspections could be performed remotely, they were conducted per the applicable IP. In some cases, portions of an IP were completed remotely and on site. The inspections documented below met the objectives and requirements for completion of the IP.
REACTOR SAFETY
71111.01 - Adverse Weather Protection
External Flooding Sample (IP Section 03.03) (1 Sample)
- (1) The inspectors evaluated that flood protection barriers, mitigation plans, procedures, and equipment are consistent with the licensees design requirements and risk analysis assumptions for coping with external flooding.
71111.04 - Equipment Alignment
Partial Walkdown Sample (IP Section 03.01) (3 Samples)
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
- (1) Vital instrument board 1-II with invertor 1-II out of service for transformer replacement on August 13, 2020 (2)1A emergency diesel generator following surveillance testing on August 26, 2020
- (3) Unit 1 and 2 6.9kV power distribution line up with 2A start bus out of service on September 20, 2020
Complete Walkdown Sample (IP Section 03.02) (1 Sample)
- (1) Unit 2 emergency diesel generators on July 13, 2020
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) Emergency Raw Cooling Water Building on July 22, 2020 (2)1A and 1B 480V Transformer Rooms on July 30, 2020
- (3) Unit 1 and Unit 2 Auxiliary Instrument Rooms on July 30, 2020 (4)2A and 2B 480V Transformer Rooms on September 8, 2020
- (5) Unit 1 Auxiliary Building, Elevation 669 on September 28, 2020
71111.06 - Flood Protection Measures
Inspection Activities - Internal Flooding (IP Section 03.01) (2 Samples)
The inspectors evaluated internal flooding mitigation protections in the:
(1)1B2 and 2A2 480V Shutdown Board Rooms, Auxiliary Bldg. El 734 (2)1A and 2A Rx MOV Board Rooms, Auxiliary Bldg. El 749
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 a power reduction following the trip of the 1A main feed pump #1 oil pump on July 22, 2020.
- (2) The inspectors observed and evaluated licensed operator performance in the main control room during load rejection and hot restart testing of 1B emergency diesel generator on August 27, 2020.
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed and evaluated a simulator training scenario on August 24, 2020.
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) Control Room Emergency Ventilation System (CREVS) would not pressurize the Main Control Room on February 29, 2020
- (2) Malfunction of turbine Analog Electro-Hydraulic system causes reactor trip and safety injection signal on May 13, 2020
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 August 2-8 including protected equipment status reviews for scheduled maintenance on R-A and J-A ERCW pumps and the A main control room chiller.
- (2) Unit 1 and 2, week of August 9-15 including protected equipment status reviews for scheduled maintenance on R-A ERCW pump, vital invertor 1-II and the switchyard bus 2-4 insulator replacement.
- (3) Unit 1 and 2, week of August 30-September 05 including protected equipment status reviews for scheduled maintenance on A main control room air conditioner, D station air compressor and dry cask spent fuel loading.
- (4) Unit 1 and 2, week of September 20-26 including protected equipment status reviews for scheduled maintenance on 2A start bus, B main control room air conditioner, 2B motor driven AFW pump and dry cask spent fuel loading.
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (5 Samples)
The inspectors evaluated the licensee's justifications and actions associated with the following operability determinations and functionality assessments:
- (1) Unit 1 Refueling Water Storage Tank Channel I Level indication (1-L-63-50) dropped to 75 percent then returned to normal (CR 1621248)
(2)1B-B DG lube oil level on Engine 1 and Engine 2 is low (CR 1633278)
- (3) Discrepancy on treatment of blended low enriched uranium (BLEU) fuel decay heat calculations at SQN (CR 1631012)
- (4) Leaking tube fitting (Section XI) on B Aux Compressor ERCW cooling water line (CR
===1636677)
- (5) B-B fire/flood mode pump failed to meet surveillance acceptance criteria (CR 1634106)
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-0-2017-061-002, Auxiliary Glycol Cooling System
71111.19 - Post-Maintenance Testing
Post-Maintenance Test Sample (IP Section 03.01)===
The inspectors evaluated the following post maintenance test activities to verify system operability and functionality:
- (1) WO 121445271, Replace 1-LT-63-50 transmitter, on August 3, 2020
- (2) WO 119362116, Replace B auxiliary air compressor, on September 10, 2020
- (3) WO 120469042, 120 VAC Vital Inverter Functional Test, after vital inverter 2-III 10-year preventive maintenance on September 16, 2020
- (4) WO 120829104, Perform MOVAT test on RHR HX A Outlet Valve 2-FCV-70-156 on September 16, 2020
71111.22 - Surveillance Testing
The inspectors evaluated the following surveillance tests:
Surveillance Tests (other) (IP Section 03.01)
(1)1-SI-OPS-082-007.A, Electrical Power System Diesel Generator 1A-A on August 24, 2020 (2)1-SI-OPS-082-024.B, 1B-B D/G 24 Hour Run and Load Rejection Testing on August 26, 2020 (3)2-SI-MIN-061-108.0, Ice Condenser Intermediate Deck Door Weekly Inspection, on September 23, 2020
RCS Leakage Detection Testing (IP Section 03.01) (1 Sample)
- (1) 0-SI-OPS-068-137.0, Reactor Coolant System Water Inventory on August 10, 2020
71114.06 - Drill Evaluation
Drill/Training Evolution Observation (IP Section 03.02) (1 Sample)
The inspectors evaluated:
- (1) A simulator drill scenario which included an earthquake, a steam generator tube rupture, and emergency plan classifications on August 24,
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 radiological protection-related instructions to plant workers.
Contamination and Radioactive Material Control (IP Section 03.03) (2 Samples)
The inspectors evaluated licensee processes for monitoring and controlling contamination and radioactive material.
- (1) Observed licensee surveys of potentially contaminated material leaving the RCA.
- (2) Observed screening of personnel leaving the RCA.
Radiological Hazards Control and Work Coverage (IP Section 03.04) (4 Samples)
The inspectors evaluated in-plant radiological conditions during facility walkdowns and observation of radiological work activities.
- (1) Movement of irradiated fuel underwater.
- (2) Welding activities on the dry cask Multi-purpose Canister (MPC) lid.
- (4) Radiological controls around the Independent Spent Fuel Storage Installation (ISFSI).
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) Loaded Hi-Trac container area on refuel floor.
- (2) Tritiated Drain Collector Tank Room.
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:
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 licensee performance as it pertains to external dosimetry that is used to assign occupational dose.
Internal Dosimetry (IP Section 03.03) (1 Sample)
The inspectors evaluated the following internal dose assessments for actual internal exposures:
- (1) The inspectors evaluated two dose assessments which resulted in CEDE doses over 10 mRem.
Special Dosimetric Situations (IP Section 03.04) (2 Samples)
The inspectors evaluated the following special dosimetric situations:
- (1) Skin dose assessment for an individual with a discrete radioactive particle on right foot.
- (2) Dose assessments for three declared pregnant workers.
71124.05 - Radiation Monitoring Instrumentation
Walkdowns and Observations (IP Section 03.01) (5 Samples)
The inspectors evaluated the following radiation detection instrumentation during plant walkdowns:
- (1) Area radiation monitors (ARMs) located in the auxiliary building.
- (2) Portable instrumentation ready to be used and located in the instrumentation lab; included observation of source checks for select instruments.
- (3) Source check demonstration on Radiologically Controled Area (RCA) exit GEM-5 portal monitor no.12PM.
- (4) Source check demonstration on RCA exit ARGOS personnel contamination monitor no. 860587.
- (5) Source check demonstration on RCA exit CRONOS-4 small article monitor no.
OTHER ACTIVITIES - BASELINE
===71151 - Performance Indicator Verification
The inspectors verified licensee performance indicators submittals listed below:
MS05: Safety System Functional Failures (SSFFs) Sample (IP Section 02.04)===
- (1) Unit 1 (July 2019 - June 2020)
- (2) Unit 2 (July 2019 - June 2020)
MS06: Emergency AC Power Systems (IP Section 02.05) (2 Samples)
- (1) Unit 1 (July 2019 - June 2020)
- (2) Unit 2 (July 2019 - June 2020)
MS07: High Pressure Injection Systems (IP Section 02.06) (2 Samples)
- (1) Unit 1 (July 2019 - June 2020)
- (2) Unit 2 (July 2019 - June 2020)
MS08: Heat Removal Systems (IP Section 02.07) (2 Samples)
- (1) Unit 1 (July 2019 - June 2020)
- (2) Unit 2 (July 2019 - June 2020)
MS09: Residual Heat Removal Systems (IP Section 02.08) (2 Samples)
- (1) Unit 1 (July 2019 - June 2020)
- (2) Unit 2 (July 2019 - June 2020)
MS10: Cooling Water Support Systems (IP Section 02.09) (2 Samples)
- (1) Unit 1 (July 2019 - June 2020)
- (2) Unit 2 (July 2019 - June 2020)
OR01: Occupational Exposure Control Effectiveness Sample (IP Section 02.15) (1 Sample)
- (1) October 2019 - July 2020
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 2019 - July 2020
71152 - Problem Identification and Resolution
Annual Follow-up of Selected Issues (IP Section 02.03) (1 Sample)
The inspectors reviewed the licensees implementation of its corrective action program related to the following issues:
- (1) Unplanned shutdown LCO entry on Unit 2 due to both trains of RVLIS upper range inoperability. (CR 1532058)
71153 - Followup of Events and Notices of Enforcement Discretion Event Report (IP Section 03.02)
The inspectors evaluated the following licensee event reports (LERs):
- (1) LER 2020-002-00 for Sequoyah Nuclear Plant, Unit 1, Safety Injection Signal with Reactor Trip Caused by a Failure with the Main Turbine Control System (ADAMS accession: ML20183A159)
The inspectors determined that it was not reasonable to foresee or correct the cause discussed in the LER therefore no performance deficiency was identified. The inspectors also concluded that no violation of NRC requirements occurred.
- (2) LER 2019-03-001, Sequoyah Nuclear Plant Unit 1 Automatic Reactor Trip due to Negative Rate Trip as a Result of a Dropped Control Rod (ADAMS accession: ML20118C456).
The inspectors reviewed the updated LER submittal. The previous LER submittal was reviewed in Inspection Report 0500327, 328/2019004. The circumstances surrounding this LER are documented in Inspection Report 0500327, 328/2019004 in the Inspection Results Section (NCV 05000327/2019004-02).
OTHER ACTIVITIES
- TEMPORARY INSTRUCTIONS, INFREQUENT AND ABNORMAL
60855.1 - Operation of an Independent Spent Fuel Storage Installation at Operating Plants Operation of an Independent Spent Fuel Storage Installation at Operating Plants
- (1) The inspectors evaluated the licensees activities related to long-term operation and monitoring of their independent spent fuel storage installation on July 15, 2020.
- (2) The inspectors evaluated the licensees independent spent fuel storage installation cask loadings on August 24 through September 25. Specifically, the inspectors observed the following activities;
- Fuel selection and fuel loading
- Heavy load movement of transfer cask (stack up)
- Drying and backfill evolutions
- Closure welding and non-destructive weld evaluations
- Transfer and transport evolutions
- Radiological field surveys
The inspectors evaluated the following change reviews:
- HPP-2244-1000, Condition 8 Thermal Test Procedure for the HI-STORM FW XL performed on September 9, 2020
===71003 - Post-Approval Site Inspection for License Renewal
From August 24 to August 27, 2020, the NRC continued monitoring TVAs performance at Sequoyah by conducting a Post-Approval Site Inspection for License Renewal - Phase III in accordance with the license renewal inspection program (LRIP). During the Phase II inspection, documented in NRC inspection report 05000327/2020011 and 05000328/2020011 (ML20079J317), the NRC identified four observations subject to follow-up inspection. The objective of this Phase III inspection was to confirm that the actions taken by the licensee to address these observations were adequate to ensure compliance with the conditions stipulated in the renewed facility operating license and to satisfy the associated license renewal commitments.
For the observations identified below, the inspectors interviewed plant personnel and reviewed the applicable license renewal program and corrective action program documents. A full description of the associated commitments is available in the UFSAR supplement for license renewal, as revised, and Appendix A of the NRC SER issued as NUREG-2181 (ML15187A206).
Post-Approval Site Inspection for License Renewal===
- (1) Observation for Commitment Item 5: Enhancements to the Diesel Fuel Oil Monitoring Program. Status: Closed.
- (2) Observation for Commitment 6: Enhancements to the External Surfaces Monitoring Program. Status: Closed.
- (3) Observation related to the Clarity of Acceptance Criteria in the Preventative Surveillance and Preventative Maintenance Program. Status: Closed.
- (4) Observation for Commitment Item 33: Enhancements to the Water Chemistry Control
- Closed Treated Water Systems Program. Status: Closed.
INSPECTION RESULTS
Failure to Establish Adequate FME Controls Results in Inoperable Reactor Vessel Level Indication System (RVLIS)
Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems
Green NCV 05000328/2020003-01 Open/Closed
[H.1] -
Resources 71152 A self-revealing green NCV of 10 CFR 50 Appendix B, Criterion V, Instructions, Procedures, and Drawings, was identified when the licensee failed to establish appropriate foreign material exclusion (FME controls associated with installation of reactor vessel level instrumentation system (RVLIS) equipment, an activity affecting quality. Specifically, the foreign material exclusion FME controls prescribed in maintenance procedure 0-MI-MRR-068-006.0, "Installation of Reactor Pressure Vessel Head and Attachments," failed to provide adequate guidance and resulted in blockage and subsequent inoperability of the upper pressure channels of the reactor vessel level instrumentation system (RVLIS).
Description:
At 0915 on July 1, 2019, while Unit 2 was in Mode 1, the reactor vessel level instrumentation system (RVLIS) upper range level channel 'A' was declared inoperable due to the channel indication being high outside of its allowable range. During troubleshooting, the licensee determined that the RVLIS upper range level channel 'B' was also increasing similar to channel 'A'. At 1436 on July 12, 2019, the RVLIS upper range level channel B was also declared inoperable. The licensee determined that the most likely cause of the RVLIS upper range level inoperability was blockage in the RVLIS upper tap on the reactor head, which is a common sensing line shared between the two channels. Because the location of the tap and associated piping and valves are inside the reactor cavity and access to this location requires lifting of the reactor vessel missile shield, further troubleshooting and repairs to the RVLIS upper range level channels was deferred until the next Unit 2 cold shutdown. The RVLIS upper range channels are used in emergency operating procedures (EOPs) to monitor for the presence of voids in the reactor vessel during natural circulation conditions in the RCS and are required by Unit 2 Technical Specification 3.3.3 to be operable in Modes 1, 2, and 3. On July 18, 2019, the licensee received approval of Exigent Technical Specification Amendment 388 for Unit 2 to operate for the remainder of Operating Cycle 23 with the upper channels of RVLIS inoperable and compensatory measures in place.
On April 13, 2020, Unit 2 was in cold shutdown with reactor disassembly in progress preparing for refueling. The RCS was vented through the pressurizer manway and the reactor head vent line. The reactor head vent line is same line which provides the RVLIS indication. This piping is disassembled to provide a vent path for the reactor head during depressurized operations. RCS level was stable in partial drain down approximately six inches below the reactor vessel flange. Technicians performing reactor head disassembly disconnected the first core exit thermocouple nozzle assembly (CETNA) and noted a strong vacuum was present on the line which was not expected. Operators in the control room noted a rapid unexpected level rise on both Mansell reactor vessel level channels. In 20 seconds, RCS level rose approximately four feet. Operators responded by controlling charging and letdown to stabilize reactor vessel level. Further investigation revealed the normal head vent was obstructed and a vacuum had been established on the head during drain down. The vacuum on the reactor head was broken by removing the CETNA seal. Level in the reactor vessel head then equalized with the pressurizer.
Two pieces of foreign material were found in the line after removal of the spool piece from the reactor head. This foreign material appears to have been the cause of the RVLIS inoperability and the reactor head vent blockage. Lab results found that the radioactivity was well embedded in the foreign material samples, which indicates that the material was present in the system for at least a cycle. The licensee was unable to determine the source of foreign material or how it entered the reactor coolant system but concluded the foreign material could have only entered the RCS due to inadequate FME controls.
Corrective Actions: Foreign material was removed from the reactor head vent line and additional FME controls were included in maintenance procedures for reactor head reassembly to include quality critical maintenance steps to inspect reactor head vent piping for foreign material prior to installation.
Corrective Action References: CR 1600942, CR 1529074, CR 1532058
Performance Assessment:
Performance Deficiency: The licensees failure to establish adequate FME controls in maintenance procedure 0-MI-MRR-068-006.0 for activities affecting quality was a performance deficiency.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Procedure Quality attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, inadequate FME controls resulted in blockage and inoperability of the upper channels of RVLIS.
Significance: The inspectors assessed the significance of the finding using Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The finding screened to Green because all questions in Exhibit 2, "Mitigating Systems Screening Questions," Section A, "Mitigating SSCs and PRA Functionality" were answered "No.
Cross-Cutting Aspect: H.1 - Resources: Leaders ensure that personnel, equipment, procedures, and other resources are available and adequate to support nuclear safety.
Enforcement:
Violation: 10 CFR 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, states in part that activities affecting quality shall be prescribed by documented procedures of a type appropriate to the circumstances. Contrary to the above, quality-related maintenance procedure 0-MI-MRR-068-006.0, section 6.8.5, Reactor Vessel Level Indicating System (RVLIS) Tubing and valve Assembly Installation, did not establish appropriate FME controls for installation of RVLIS equipment.
Enforcement Action: This violation is being treated as an non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
Observation: Documenting multiple events in one LER 71153 During closure review of LER 05000327/2019-003-01, the inspectors noted that the licensee had inappropriately documented multiple unrelated events in one LER. On August 27, 2019, Sequoyah Nuclear Plant, Unit 1, automatically tripped as a result of Control Bank D, Control Rod H-8 dropping into the core. During the post trip review, the licensee identified that Steam Generator #3 pressure Transmitter 1-PT-1-23 demonstrated sluggish behavior. Further review determined that the transmitter had been inoperable since November 2015. The licensee reported both of these events on October 23, 2019 in LER 05000327/2019-003-00. At the time of the October 23, 2019 submission, the causes of the two events were still under investigation (separate cause evaluations). However, sufficient information was available at that time to determine that the two events did not have the same general cause or consequence.
LER 05000327/2019-003-01 was submitted on April 25, 2020 to update the results of the causal analyses and associated corrective actions. The root cause of the H-8 control rod failure was excessive wear to stationary gripper latch mechanism resulting in the inability to maintain the control rod in the fully, or nearly fully, withdrawn position for an extended period of time. The inspectors did not identify any performance deficiencies associated with the H-8 control rod failure. The root cause for 1-PT-1-23 failure was determined to be a procedural issue associated with post maintenance testing. The violation associated with this issue was documented in IR 05000327, 328/2019004 (NCV 05000327/2019004-02).
NUREG-1022 Revision 3, Section 2.3, states in part that more than one failure or event may be reported in a single LER if
- (1) the failures or events are related (i.e., they have the same general cause or consequences) and
- (2) they occurred during a single activity. NUREG-1022 further states that unrelated events or conditions should not be reported in one LER. The residents concluded that, per NUREG-1022 guidance, the two events should have been reported under separate LERs. There was no performance deficiency or violation associated with this observation.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On October 26, 2020, the inspectors presented the integrated inspection results to Mr.
Scott Hunnewell and other members of the licensee staff.
- On August 27, 2020, the inspectors presented the Phase III License Renewal Inspection Exit inspection results to M. Rasmussen, Site VP and other members of the licensee staff.
- On August 28, 2020, the inspectors presented the Radiation Protection Inspection inspection results to Matt Rasmussen and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
71003
Corrective Action
Documents
CR1583096,
CR1583386,
CR1586277
Corrective Action
Documents
Resulting from
Inspection
CR1633513
Miscellaneous
NCO114438429
U1 &
NCO114439064
U2
Commitment Change Evaluation Form for Diesel Fuel
Monitoring Program
2/28/2020
SAR Change
Package No. 29-
Changes to Commitment 5.C. for the Diesel Fuel Monitoring
Program
Procedures
0-PI-DXX-000-
100.06.1
Insulated Component External Surfaces Inspection
Rev. 0002
0-PI-DXX-000-
100.06.1
Insulated Component External Surfaces Inspection
Rev. 0000
0-PI-DXX-000-
100.06.2
Uninsulated Components External Surfaces Inspection
Rev. 0003
0-PI-DXX-000-
100.06.2
Uninsulated Components External Surfaces Inspection
Rev. 0000
0-PI-DXX-000-
100.24.1
Periodic Surveillance and Preventive Maintenance Program
Inspections
Rev. 0003
0-SI-MIN-018-
2.0
Cleaning of the 7-Day Diesel Fuel Oil Storage Tanks
Rev. 0006
0-TPP-DXX-000-
100.06
License Renewal Aging Management Program Basis
Document: External Surfaces Monitoring Program
Rev. 0001
0-TPP-DXX-000-
100.06
License Renewal Aging Management Program Basis
Document: External Surfaces Monitoring Program
Rev. 0002
0-TPP-DXX-000-
100.24
License Renewal Aging Management Program Basis
Document: Periodic Surveillance and Preventative
Rev. 0001
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Maintenance Program
NPG-SPP-
09.0.1.1
System Monitoring and Trending
Rev. 0002
NPG-SPP-
09.0.1.1
System Monitoring and Trending
Rev. 0005
NPG-SPP-09.7.1
Corrosion Control - General, Localized and Galvanic, and
Stress Corrosion Cracking Program
Rev. 0006
NPG-SPP-09.7.1
Corrosion Control - General, Localized and Galvanic, and
Stress Corrosion Cracking Program
Rev. 0004
PM120212
Inspect Surface Condition of Piping in the Water Line
Region of the Containment Waste Disposal Floor and
Equipment Sumps
PM120213
Inspect Surface Condition of Piping in the Water Line
Region of the Containment Waste Disposal Floor and
Equipment Sumps
PM123394
External Piping Inspection on System 026 Piping for Loss of
Material due to MIC
PM123395
Perform Internal Surface Inspection of Stainless Steel Piping
and Associated Valves for Systems 040 and 305
PM126893
Inspect Surface Condition of the Reactor Coolant Pump Oil
Spillage Protection System Drain Piping
PM127642
Perform Wall Thickness Examinations for Loss of Material
on Carbon Steel Piping and Equipment associated with the
Cask Decontamination Collector Tank
PM74444
Perform NDE Exams on SQN-2-TNK-002-0232, Condensate
Storage Tank B, for License Renewal
PM74447
Perform NDE Exams on SQN-1-TNK-002-0229, Condensate
Storage Tank A, for License Renewal
Corrective Action
Documents
CR 1391761
Fire/Flood Mode Pump B-B failed to meet acceptance
criteria
2/28/2018
CR 1528706
Fire/Flood Mode Pump B-B failed to meet acceptance
criteria
06/28/2019
Corrective Action
Documents
CR 1634106
Perform Functional Evaluation of B-B Fire/Flood Mode Pump 08/30/2020
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Resulting from
Inspection
Miscellaneous
SQN-DC-V-12.1
Design Criteria Document Sequoyah Nuclear Plant - Flood
Protection Provisions
Revision 18
Work Orders
0-PI-OPS-026-073.B Fire/Flood Mode Pump B-B Flow Test
06/28/19
Procedures
0-SO-202-1
6900V Start Buses
Revision 35
0-SO-250-2
20 Volt AC Vital Instrument Power System
Revision 73
0-SO-82-1
Diesel Generator 1A-A
Revision 62
0-SO-82-3
Diesel Generator 2A-A
Revision 68
0-SO-82-4
Diesel Generator 2B-B
Revision 64
Fire Plans
AUX-0-669-01
Pre-Fire Plan Auxiliary Building - El. 669 (Unit 1 Side)
Revision 8
AUX-0-749-01
Pre-Fire Plan Auxiliary Bldg, Elevation 749 (Unit 1/Non-RCA
Side)
Revision 7
AUX-0-749-02
Pre-Fire Plan Auxiliary Bldg, Elevation 749 (Unit 2/Non-RCA
Side)
Revision 13
CON-0-685-00
Pre-Fire Plan Control Building, El 685
Revision 6
ERCW-0-688-00
Pre-Fire Plan Essential Raw Cooling Water Pump Station,
Elevation 688
Revision 2
ERCW-0-704-00
Pre-Fire Plan Essential Raw Cooling Water Pump Station,
Elevation 704
Revision 2
ERCW-0-720-00
Pre-Fire Plan Essential Raw Cooling Water Pump Station,
Elevation 720
Revision 3
Procedures
Revision 6
71111.11Q Miscellaneous
SEG
OPL273S2013
SGTR ECA-3.3
07/10/2020
Corrective Action
Documents
CR 1591012
0-SI-SFT-031-144.B, "Control Room Emergency Ventilation
System Test" **Failed Test Low**
2/29/2020
CR 1591382
Inadequate PM frequency change adversely affecting
CREVS pressure test
03/02/2020
CR 1607726
Unit 1 reactor trip and safety injection
05/13/2020
CR1591999
CREVS Margin Management Optimization
03/03/2020
Miscellaneous
Cause
Determination
Evaluation (CDE)
During performance of 0-SI-SFT-031-144.B, 'B' Train
CREVS would not pressurize the MCR
03/16/2020
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
3100
Cause
Determination
Evaluation (CDE)
3112
Functional failure of AEC speed error card causes reactor
trip and safety injection
08/17/2020
Procedures
0-GO-16
System Operability Checklist
Revision 25
NPP-SPP-07.3.04 Protected Equipment
Revision 6
Calculations
PFE-4090
Calculation of BLEU Fuel Decay Heat Adders for SQN Dry
Cask Campaigns 10 and 12
Revision 0
Corrective Action
Documents
Condition Reports
(CRs) 1630182;
Operability
Evaluations
Functional Evaluation for CR 1634106
09/04/2020
Engineering
Changes
SQN-0-2017-061-
2
Auxiliary Glycol Cooling System
Revision 3
Corrective Action
Documents
CR 1620883
Revise 0-MI-MMR-032-001.0 to include refurbished
compressor performance test
07/06/2020
CR 1636677
Leaking tube fitting (Section XI) on B Aux Compressor
ERCW cooling water line
09/10/2020
Procedures
0-MI-IRT-099-
10B.0
Response Time Test Instructions Using SG-1M
Revision 3
0-MI-MMR-032-
001.0
Auxiliary Control Air Compressor Rebuild
Revision 12
1-SI-ICC-063-
050.1
Channel Calibration of RWST Level Channel I Rack 3 Loop
1-L-63-50
Revision 19A
1-SI-IRT-099-15A
Response Time Test of RWST Level Transmitter 1-LT-63-50
Cycle A
Revision 0A
Corrective Action
Documents
CR 1633278
1B-B DG Lube Oil Level on Engine 1 and Engine 2 is Low
08/26/2020
CR 1633693
Lesson Learned from Post Job Critique for oil add to 1-B
08/28/2020
20 Spent Fuel Storage Campaign 13
08/05/2020
Corrective Action
Documents
CR 1560213
CR 1567371
Radiation Work
20001063
LHRA activities in cask work area
Revision 0
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Permits (RWPs)
Calculations
TEDE-2020-015
04/20/2020
Calibration
Records
E44608
Certificate No:
179670
Pressure Detector Report of Calibration
2/12/2020
E46103
Certificate No:
184268
Digital Pressure Gauge Report of Calibration
06/22/2020
E47610
Certificate No:
183504
Air Velocity Meter Report of Calibration
06/05/2020
Corrective Action
Documents
CRs 1531822,
1542138,
262766 and
1579592.
Corrective Action Reports
Various
Miscellaneous
e-mail from R.
Baxley to A.
McNeil
Request for Additional Information - List of Control Room
Operators on-duty as of 08/26/2020 (until noon)
08/26/2020
SN: 11040
Grade D Air Certification
04/12/2018
SN: 11040
Grade D Air Certification
08/09/2017
SN: 11040
Grade D Air Certification
04/12/2019
Student Qual
Details Report
08/27/2020
Operability
Evaluations
0-SI-SFT-031-
144.A
Control Room Emergency Ventilation Test Train A
06/11/2019
0-SI-SFT-031-
144.B
Control Room Emergency Ventilation Test Train B
03/04/2020
Procedures
0-PI-FPU-049-
401.M
Self Contained Breathing Apparatus
Rev. 31
0-SO-30-10
Auxiliary Building Ventilation System
Rev. 66
0-SO-30-18
Auxiliary Building Gas Treatment System
Rev. 16
0-SO-30-3
Containment Purge System Operation
Rev. 56
0-SO-30-8
Containment Pressure Control
Rev. 38
0-TI-FPU-049-
Breathing Air Compressor Operation
Rev. 1
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
001.0
NISP-RP-003
Radiological Air Sampling
Rev. 1
NISP-RP-008
Use and Control of HEPA Filtration and Vacuum Equipment
Rev. 1
NPG-SPP-05.10
Radiological Respiratory Protection Program
Rev. 5
NPG-SPP-05.2.5
Rev. 3
RCDP-21
Radiological Air Sample
Rev. 0
RCDP-24
Maintenance and Field Setup of HEPA Units and Vacuums
Rev. 1
RCI-04
Respiratory Protection Program
Rev. 58
RCI-04.01
Issue and Use of Respiratory Protection Devices
Rev. 12
RCI-04.02
Cleaning/Sanitizing, Maintenance, Inspection, Storage and
Inventory of Respiratory Protection Devices
Rev. 7
RCI-04.03
Respiratory Protection Program Periodic Evaluation
Rev. 0
RCI-102
Radiation Protection Technical Support Instrumentation and
Respiratory Practices
Rev. 6
RCTP-101
Operation of the Mask Fit System
Rev. 10
Self-Assessments SQN-RP-SSA-16-
007
In-plant airborne radioactivity control and mitigation self-
assessment.
03/21/2016
Work Orders
20244041,
203001482,
20270158 and
20272861
Various
Corrective Action
Documents
CRs# 1488494,
1494045,
1556586,
1556831,
1560628,
1565327, and
1567371.
Corrective Action Reports
Various
Miscellaneous
2018 Annual
Evaluation of
Area Dosimetry
Results
2018 Evaluation of Area Dosimetry Results
2/04/2019
2018
Radionuclide
2018 Alpha Characterization Report
01/27/2020
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Trending Report
20 NVLAP
Accreditation
Certificate
20 NVLAP Accreditation Certificate
non-dated
SQN Site Specific
Neutron
Characterization
Report
SQN Neutron Characterization Report
Rev. 2
(DRAFT)
Procedures
NISP-RP-006
Personnel Contamination Monitoring
Rev. 1
NPG-SPP-05.1
Radiological Controls
Rev. 11
NPG-SPP-05.1.1
Alpha Radiation Monitoring Program
Rev. 7
NPG-SPP-05.9
Radiological Control and Radioactive Material Shipment
Augmented Quality Assurance Program
Rev. 6
RCDP-10
Personnel Contamination Event Documentation
Rev. 9
RCDP-13
Centralized Inprocessing Facility Activities
Rev. 7
RCDP-15
Dosimetry Operations
Rev. 4
RCDP-7
Bioassay and Internal Dose Program
Rev. 9
RCI-03
Personnel Monitoring
Rev. 51
RCI-103
Radiation Protection Technical Support - Dosimetry
Routines
Rev. 4
RCI-23
Radiation Protection Records
Rev. 13
RCTP-104
Operation of the ORTEC Standfast Whole Body Counting
System
Rev. 6
RCTP-105
Personnel In-Processing and Dosimetry Administrative
Process
Rev. 10
RCTP-106
Special Dosimetry Operations
Rev. 7
RCTP-110
Operation of the F&J L-12P Lapel Air Sampler
Rev. 4
RCTP-114
Planned Special Exposures
Rev. 0
Radiation
Surveys
DAW 2017-02-15
Radman Nuclide
Distribution
Nuclide Distribution Report
2/15/2017
DAW 2018-11-15
Radman Nuclide
Distribution
Nuclide Distribution Report
11/15/2018
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Resin 2018-06-03
Radman Nuclide
Distribution
Nuclide Distribution Report
06/03/2018
Self-Assessments SQN-RP-SA-19-
005
Occupational Dose Assessment
10/12/2018
71151
Miscellaneous
MSPI Derivation Reports - Unit 1 and Unit 2 Residual Heat
Removal System
09/15/2020
MSPI Derivation Reports - Unit 1 and Unit 2 Cooling Water
System
09/15/2020
MSPI Derivation Reports - Unit 1 and Unit 2 High Pressure
Injection System
09/15/2020
2019 Annual
Radioactive
Effluent Release
Report
2019 Annual Radioactive Effluent Release Report
04/24/2020
SI-422.1
Monthly 10 CFR 50 Appendix I Dose Calculations for Liquid
and Gaseous Effluents (2019 Data)
01/02/2020
Procedures
NPG-SPP-02.2
Performance Indicator Program
Rev. 13
Corrective Action
Documents
CR 1529074
2-LI-68-369 RVLIS Upper Range Indicating Outside of
Allowable Range
07/10/2019
CR 1600942
Foreign Material Found in Unit 2 RVLIS Line
04/12/2020
Corrective Action
Documents
CR 1607726
Unit 1 reactor trip and safety injection
05/13/2020