IR 05000336/2020004

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Integrated Inspection Report 05000336/2020004 and 05000423/2020004
ML21032A099
Person / Time
Site: Millstone  Dominion icon.png
Issue date: 02/01/2021
From: Daniel Schroeder
Reactor Projects Branch 2
To: Stoddard D
Dominion Energy
Schroeder D
References
IR 2020004
Download: ML21032A099 (32)
v • d • e


Text

February 1, 2021

SUBJECT:

MILLSTONE POWER STATION, UNITS 2 AND 3 - INTEGRATED INSPECTION REPORT 05000336/2020004 AND 05000423/2020004

Dear Mr. Stoddard:

On December 31, 2020, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Millstone Power Station, Units 2 and 3. On January 14, 2021, the NRC inspectors discussed the results of this inspection with Mr. John Daugherty, Site Vice President and other members of your staff. The results of this inspection are documented in the enclosed report.

Two findings of very low safety significance (Green) are documented in this report. Both of these findings involved violations of NRC requirements. One Severity Level IV violation without an associated finding is documented in this report. We are treating these violations as non-cited violations (NCVs) consistent with Section 2.3.2 of the Enforcement Policy.

Licensee-identified violations which were determined to be of very low safety significance are documented in this report. We are treating these violations as NCVs 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 I; the Director, Office of Enforcement; and the NRC Resident Inspector at Millstone Power Station, Units 2 and 3.

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 I; and the NRC Resident Inspector at Millstone Power Station, Units 2 and 3. 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, X /RA/

Signed by: Daniel L. Schroeder Daniel L. Schroeder, Chief Reactor Projects Branch 2 Division of Reactor Projects Docket Nos. 05000336 and 05000423 License Nos. DPR-65 and NPF-49

Enclosure:

As stated

Inspection Report

Docket Numbers: 05000336 and 05000423 License Numbers: DPR-65 and NPF-49 Report Numbers: 05000336/2020004 and 05000423/2020004 Enterprise Identifier: I-2020-004-0033 Licensee: Dominion Energy Nuclear Connecticut, Inc.

Facility: Millstone Power Station, Units 2 and 3 Location: Waterford, CT 06385 Inspection Dates: October 1, 2020 to December 31, 2020 Inspectors: J. Fuller, Senior Resident Inspector E. Allen, Resident Inspector E. Bousquet, Resident Inspector J. Bream, Reactor Operations Engineer K. Mangan, Senior Reactor Inspector P. Ott, Operations Engineer D. Silk, Senior Operations Engineer A. Turilin, Reactor Inspector S. Wilson, Senior Health Physicist Approved By: Daniel L. Schroeder, Chief Reactor Projects Branch 2 Division of Reactor Projects Enclosure

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring Dominions performance by conducting an integrated inspection at Millstone Power Station, Units 2 and 3, 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. Licensee-identified non-cited violations are documented in report sections: 71114.05 and 71124.0

List of Findings and Violations

Failure to Follow Seismic Housekeeping Requirements for Movable Carts, Ladders,

Toolboxes and Filing Cabinets Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green [H.12] - Avoid 71111.04 Systems NCV 05000336,05000423/2020004-01 Complacency Open/Closed The inspectors identified a Green finding and associated non-cited violation (NCV) of 10 CFR Part 50, Appendix B, Criterion V, "Instructions, Procedures, and Drawings," when Dominion failed to follow the requirements of Station Procedure CM-AA-SHK-101, Seismic Housekeeping, Revision 6. Specifically, Dominion failed to secure multiple commodities located near seismically sensitive equipment in seismic housekeeping areas at both Unit 2 and Unit 3.

Failure to Control Transient Combustibles in Accordance with Fire Protection Program Procedure Cornerstone Significance Cross-Cutting Report Aspect Section Initiating Events Green [H.12] - Avoid 71111.05 NCV 05000423/2020004-02 Complacency Open/Closed The inspectors identified a Green finding and associated NCV of Millstone Unit 3 License Condition 2.H, Fire Protection, when Dominion failed to implement and maintain in effect all provisions of the approved Fire Protection Program. Specifically, on September 30, 2020, the inspectors identified eight, non-permitted, 275-gallon totes left unattended in the Unit 3 Auxiliary Building North Floor Area (Fire Area AB-1A), which was not in accordance with Attachment 1 of procedure CM-AA-FPA-101, Control of Combustible and Flammable Materials, and exceeded the limits provided by the fire severity calculation of record.

Main Steam Safety Relief Valve Lift Setpoint Exceeds Technical Specification Allowable Value, Closure of LER 05000336/2020-001-00, Failure of Two Main Steam Safety Valves to Lift Within the Technical Specification Acceptance Criteria Cornerstone Significance Cross-Cutting Report Aspect Section Not Applicable NCV 05000336/2020004-03 Not Applicable 71153 Open/Closed A self-revealed Severity Level IV NCV of Technical Specification (TS) 3.7.1.1 was identified when Dominion discovered, through as-found surveillance testing, that two main steam safety relief valves (MSSVs) had lift pressure setpoints that were not within TS lift setting tolerance.

Additional Tracking Items

Type Issue Number Title Report Section Status LER 05000336/2020-001-00 LER 2020-001-00 for 71153 Closed Millstone Power Station, Unit 2, Failure of Two Main Steam Safety Valves to Lift Within the Technical Specification Acceptance Criteria

PLANT STATUS

Unit 2 began the inspection period at rated thermal power. On November 15, 2020, Unit 2 power was reduced to approximately 83 percent rated thermal power due to degrading circulating water box conditions during a storm with high winds and heavy rain. Unit 2 was returned to full rated thermal power on November 16, 2020, and remained at or near rated thermal power for the remainder of the inspection period.

On October 1, 2020, Unit 3 was shut down for a scheduled refueling outage. Unit 3 was returned to rated thermal power on November 15, 2020. On December 28, 2020, Unit 3 power was reduced to 88 percent to isolate an emergent tube leak on the 5C feedwater heater. On December 30, 2020, Dominion reduced reactor power to 16 percent rated thermal power and took the turbine offline to facilitate inspection and repair of the 5C feedwater heater. On December 31, 2020, Dominion shut down the reactor to Mode 3 (0 percent rated thermal power)to complete repairs of the 5C feedwater heater. Unit 3 returned to full rated thermal power on January 7,

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

Seasonal Extreme Weather Sample (IP Section 03.01) (2 Samples)

(1) The inspectors evaluated readiness for seasonal extreme weather conditions prior to the onset of seasonal cold temperatures for the following systems:
  • Unit 2 condensate storage tank winter freeze protection
(2) The inspectors evaluated readiness for seasonal extreme weather conditions prior to the onset of seasonal cold temperatures for the following systems:
  • Unit 3 engineered safety features building ventilation and air conditioning
  • Unit 3 condensate storage tank heating loop

71111.04 - Equipment Alignment

Partial Walkdown Sample (IP Section 03.01) (4 Samples)

The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:

(1) Unit 3 reactor coolant system loops during the planned refueling outage on October 15, 2020
(2) Unit 3 'B' and 'D' auxiliary feedwater trains inside containment following check valve overhaul on November 6, 2020
(3) Unit 3 demineralized water storage tank to the 'A' motor driven auxiliary feedwater pump, 'B' motor driven auxiliary feed water pump, and the turbine driven auxiliary feedwater pump on November 13, 2020
(4) Unit 2 and Unit 3 electric and diesel fire pumps and fire water supply from October 20 to October 23, 2020

Complete Walkdown Sample (IP Section 03.02) (2 Samples)

(1) The inspectors evaluated system configurations during a complete walkdown of the Unit 3 high pressure safety injection system on October 9, 2020.
(2) The inspectors evaluated system configurations during a complete walkdown of the Unit 3 safety injection accumulator tanks and other associated portions of the low pressure safety injection system during the Unit 3 refueling outage (3R20) on November 5, 2020.

71111.05 - Fire Protection

Fire Area Walkdown and Inspection Sample (IP Section 03.01) (3 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 2 hydrogen seal oil unit (fire area T-1B) on October 16, 2020
(2) Unit 3 north floor area on the 4'6" elevation (fire area AB-1A) on October 1, 2020
(3) Unit 3 all elevations of containment (fire area RC-1) from October 2 - October 23, 2020

71111.08P - Inservice Inspection Activities (PWR) PWR Inservice Inspection Activities Sample (IP Section 03.01)

Main article: IP 71111.08
(1) The inspectors verified that the reactor coolant system boundary, reactor vessel internals, risk-significant piping system boundaries, and containment boundary are appropriately monitored for degradation and that repairs and replacements were appropriately fabricated, examined, and accepted by reviewing the following activities from October 13, 2020 to October 29, 2020:

03.01.a - Nondestructive Examination and Welding Activities.

  • Manual ultrasonic testing of the pressurizer spray nozzle to head weld, 03-007-SW-E (NDE Report M3-UT-20-001)
  • Manual ultrasonic testing of the pressurizer surge line elbow to pipe, RCS-SL3-SW-D (NDE Report M3-UT-20-034)
  • Manual ultrasonic testing of reactor coolant drain-line Loop B elbow to pipe,

===408005-FW-2 (NDE Report M3-UT-20-016)

  • Visual examination of reactor vessel interior, 03-001-003 (NDE Report M3-VT-20-068)
  • Peening of the reactor pressure vessel head penetration nozzles in accordance with MRP-335-R3A 03.01.c - Pressurized-Water Reactor Boric Acid Corrosion Control Activities.
  • Boric Acid Evaluation for 3RCS*SV8095A (CR1157121)

71111.11A - Licensed Operator Requalification Program and Licensed Operator Performance

Requalification Examination Results (IP Section 03.03) ===

Main article: IP 40800
(1) The inspectors reviewed and evaluated the licensed operator examination failure rates for the requalification annual operating exam for Millstone Unit 2 completed on December 11, 2020.
(2) The inspectors reviewed and evaluated the Unit 3 licensed operator requalification exam results for the annual operating exam and biennial written exam on December 15, 2020.

71111.11B - Licensed Operator Requalification Program and Licensed Operator Performance

Licensed Operator Requalification Program (IP Section 03.04) (1 Partial)

(1) (Partial)

Biennial Requalification Written Examinations The inspectors evaluated the quality of the licensed operator biennial requalification written examination administered on December 10, 2020.

Annual Requalification Operating Tests The inspectors evaluated the adequacy of Dominions annual requalification operating test.

Requalification Examination Security The inspectors evaluated the ability of Dominion 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 Dominion, and reviewed the adequacy of re-examinations for licensed operators who did not pass a required requalification examination.

Operator License Conditions The inspectors evaluated Dominions program for ensuring that licensed operators meet the conditions of their licenses.

Control Room Simulator The inspectors evaluated the adequacy of Dominions 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 Dominions 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)

(2 Samples)

(1) The inspectors observed and evaluated licensed operator performance in the control room during turnover and testing of the Unit 2 A EDG on December 2, 2020.
(2) The inspectors observed and evaluated licensed operator performance in the Unit 3 control room during main turbine operation, turbine over speed testing, plant start up (reactivity control), pressurizer pressure control, response to annunciator system main board 4 rod position indication non-urgent failure, and response to abnormal operating procedure instrument failure, on November 12, 2020.

Licensed Operator Requalification Training/Examinations (IP Section 03.02) (2 Samples)

(1) The inspectors observed and evaluated licensed operator requalification training in the Unit 2 simulator on November 17, 2020.
(2) The inspectors observed and evaluated licensed operator requalification training in the Unit 3 simulator and classroom on December 1, 2020.

71111.12 - Maintenance Effectiveness

Maintenance Effectiveness (IP Section 03.01) (3 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) Unit 3 'C' service water strainer failure on October 1, 2020 (CR1156679 and CA8154477)
(2) Unit 3 valve 3FWA*HV36A (turbine driven auxiliary feedwater control valve) failed to meet closed stroke time requirements on November 3, 2020 (CR1160047)
(3) Review of Dominion's maintenance rule (a)(3) periodic evaluation for the period of July 1, 2018 to December 31, 2019

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management Sample (IP Section 03.01) (6 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 2 elevated risk ("yellow" online risk) due to emergent removal of reserve station service transformer due to the need to remove a bird nest on October 3, 2020
(2) Unit 2 planned elevated risk during the Unit 3 reserve station service transformer replacement resulting in one offsite circuit inoperable for more than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> as permitted by the one-time 35-day allowed outage time described in Technical Specification 3.8.1, A.C. Sources (October 2020)
(3) Unit 2 elevated risk for planned maintenance on the 'A' reactor building component cooling water, reactor protection system testing, and emergent work on the 'B' charging pump on December 8, 2020
(4) Unit 3 elevated risk during decreased inventory and high decay heat at the beginning of the Unit 3 refueling outage from October 7 to October 9, 2020
(5) Unit 3 evaluation of 'B' train protected equipment during the 'A' service water train outage, which resulted in a "yellow" shutdown risk classification on October 13, 2020
(6) Unit 3 elevated risk during troubleshooting emergent failure of the 'B' emergency generator load sequencer, which resulted in an inoperable EDG while one of the two offsite power sources and the turbine driven auxiliary feedwater pump were also inoperable on November 6, 2020.

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment (IP Section 03.01) (1 Sample)

The inspectors evaluated Dominion's justifications and actions associated with the following operability determinations and functionality assessments:

(1) Unit 3 'B' EDG load sequencer autotester failure on November 24, 2020 (CR1161394)

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) Unit 3 EDG fuel rack roll pin replacement (MP3-20-01179 and CR1158433)permanent change

71111.19 - Post-Maintenance Testing

Post-Maintenance Test Sample (IP Section 03.01) (7 Samples)

The inspectors evaluated the following post-maintenance test activities to verify system operability and functionality:

(1) Unit 2 'A' EDG monthly slow start operability test on December 2, 2020 after preventive maintenance and jacket water (JW) leak repair from November 30 to December 2, 2020
(2) Unit 3 service water operational test and after replacement of the 'C' service water strainer septums on October 2, 2020
(3) Unit 3 inspection and testing of service water blowdown piping and welds (American Society of Mechanical Engineers (ASME) class III pressure boundary piping) that were found leaking and repaired on October 13, 2020 (WO53203296144)
(4) Unit 3 testing for design change MP3-19-01143, which added cobalt alloy hard facing to the residual heat removal pump suction valve from reactor coolant system (3RHS*MV8701B) on October 24, 2020
(5) Unit 3 'D' train steam generator check valve isolation (3FWA*V885) full stroke acoustic test following check valve overhaul (WO53103024991) on October 29, 2020
(6) Unit 3 3RHS*HCV607, residual heat removal flow control valve, after positioner replacement on November 4, 2020
(7) Unit 3 emergency generator load sequencer after replacement of failed card that caused spurious actuation of 'B' train emergency core cooling system components on November 6, 2020

71111.20 - Refueling and Other Outage Activities

Refueling/Other Outage Sample (IP Section 03.01) (2 Samples)

(1) The inspectors evaluated Unit 3 refueling outage 3R20 activities from October 1 to November 15, 2020
(2) The inspectors evaluated Unit 3 forced outage activities associated with the inspection and repair of the 'C' 5th point feedwater heater (3CNM-E5C) on December 31, 2020.

71111.22 - Surveillance Testing

The inspectors evaluated the following surveillance tests:

Surveillance Tests (other) (IP Section 03.01)

Main article: IP 71111.22
(1) Unit 2 turbine driven auxiliary feedwater pump and recirculation check valve inservice test on November 2, 2020
(2) Unit 3 full stroke test of cold leg injection check valve 3SIH*V28 on October 30, 2020
(3) Unit 3 turbine driven auxiliary feedwater pump comprehensive pump and check valve full flow test on November 6, 2020

Inservice Testing (IP Section 03.01) (1 Sample)

(1) Unit 2 containment spray pump and minimum recirculation check valve inservice testing on December 21, 2020

Containment Isolation Valve Testing (IP Section 03.01) (1 Sample)

(1) Unit 3 failed local leak rate testing on fire water containment isolation valve 3FPW- V3341A on October 20, 2020 (WO53203245511 and CR1158810)

FLEX Testing (IP Section 03.02) (1 Sample)

(1) Beyond design basis reactor coolant system injection pump MP-BDB-P3A on December 7, 2020

71114.02 - Alert and Notification System Testing

Inspection Review (IP Section 02.01-02.04) (1 Sample)

(1) As a result of the 2020 COVID-19 Public Health Emergency, Dominion requested and received an exemption to reschedule their biennial emergency preparedness exercise from 2020 to 2021 (ML20287A273). The inspectors performed the emergency preparedness program inspection scheduled for 2021 in its place.

The inspectors evaluated Dominion's maintenance and testing of the Millstone alert and notification system on September 28 to October 1, 2020 for the period of August 2019 through August 2020.

71114.03 - Emergency Response Organization Staffing and Augmentation System

Inspection Review (IP Section 02.01-02.02) (1 Sample)

(1) The inspectors evaluated the readiness of Dominion's Emergency Preparedness Organization on September 28 to October 1, 2020.

71114.04 - Emergency Action Level and Emergency Plan Changes

Inspection Review (IP Section 02.01-02.03) (1 Sample)

(1) The inspectors evaluated the following submitted Emergency Action Level and Emergency Plan changes onsite on September 28 to October 1, 2020.

71114.05 - Maintenance of Emergency Preparedness

Inspection Review (IP Section 02.01 - 02.11) (1 Sample)

(1) The inspectors evaluated the maintenance of the emergency preparedness program on September 28 to October 1, 2020 for the period of August 2019 through August

RADIATION SAFETY

71124.01 - Radiological Hazard Assessment and Exposure Controls

Radiological Hazard Assessment (IP Section 03.01) (1 Sample)

(1) The inspectors evaluated how Dominion identifies the magnitude and extent of radiation levels and the concentrations and quantities of radioactive materials and how Dominion 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 Dominion processes for monitoring and controlling contamination and radioactive material.

(1) The inspectors observed Dominion surveys of potentially contaminated material leaving the radiologically controlled area (RCA).
(2) The inspectors observed workers exiting the RCA at Unit 2.

Radiological Hazards Control and Work Coverage (IP Section 03.04) (5 Samples)

The inspectors evaluated in-plant radiological conditions during facility walkdowns and observation of radiological work activities.

(1) The inspectors verified electronic alarming dosimeter dose and dose rate alarm set points were based on current radiological survey data and plant procedures.
(2) The inspectors evaluated the work controls and dosimetry used for activities where dose rate gradients could be severe.
(3) The inspectors reviewed radiological surveys of conditions of work areas within the RCA.
(4) The inspectors observed maintenance personnel performing work on the Unit 2 A reactor building component cooling water heat exchanger.
(5) The inspectors observed scaffold builders erecting scaffold around the Unit 2 spent fuel pool heat exchangers with a modified radiation work permit dose setpoints due to elevated dose in the area.

High Radiation Area and Very High Radiation Area Controls (IP Section 03.05) (3 Samples)

The inspectors evaluated Dominion controls of the following High Radiation Areas and Very High Radiation Areas:

(1) The inspectors reviewed the circumstances of Technical Specification High Radiation Area Occurrences, as defined by Nuclear Energy Institute guidance document number 99-02.
(2) The inspectors reviewed procedures for changes since the last inspection to determine the adequacy of access controls for high radiation and very high radiation areas.
(3) The inspectors verified locked high radiation area controls for various areas within the Unit 2 RCA.

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.

71124.05 - Radiation Monitoring Instrumentation

Calibration and Testing Program (IP Section 03.02) (3 Samples)

The inspectors evaluated the calibration and testing of the following radiation detection instruments:

(1) Unit 3 vent gaseous effluent monitor number 3HVR10B (Kaman KDB Beta scintillation detector)
(2) Unit 3 supplemental leakage collection and release system gaseous effluent monitor number 3HVR19B (Kaman KDB Beta scintillation detector)
(3) Unit 3 engineered safety features (ESF) gaseous effluent monitor number 3HVQ49 (Kaman KDB Beta scintillation detector)

OTHER ACTIVITIES - BASELINE

===71151 - Performance Indicator Verification The inspectors verified Dominion performance indicators submittals listed below:

EP01: Drill/Exercise Performance (IP Section 02.12) ===

Main article: IP 71151
(1) September 1, 2019 to June 30, 2020

EP02: ERO Drill Participation (IP Section 02.13) (1 Sample)

(1) September 1, 2019 to June 30, 2020

EP03: Alert & Notification System Reliability (IP Section 02.14) (1 Sample)

(1) September 1, 2019 to June 30, 2020

OR01: Occupational Exposure Control Effectiveness Sample (IP Section 02.15) (1 Sample)

(1) Unit 2 (October 1, 2019 through September 30, 2020)

Unit 3 (October 1, 2019 through September 30, 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) Unit 2 (October 1, 2019 through September 30, 2020)

Unit 3 (October 1, 2019 through September 30, 2020)

71152 - Problem Identification and Resolution

Semiannual Trend Review (IP Section 02.02) (1 Sample)

(1) The inspectors reviewed a sample of troubleshooting plans and associated condition reports for equipment issues at both Unit 2 and Unit 3 to determine whether plant equipment issues that required troubleshooting to resolve were indicative of an adverse trend or more significant safety issue.

Annual Follow-up of Selected Issues (IP Section 02.03) (2 Samples)

The inspectors reviewed Dominions implementation of its corrective action program related to the following issues:

(1) Unit 3 EDG JW piping leakage corrective actions and extent of condition
(2) Condition Report CA7464616, Flanged Unit 2 Target Rock Pressurizer Power Operated Relief Valves (PORV) Exhibiting Leakage at normal operating pressure/normal operating temperature (NOP/NOT)

71153 - Follow-up of Events and Notices of Enforcement Discretion Event Follow-up (IP Section 03.01)

Main article: IP 71153
(1) The inspectors evaluated the Unusual Event (EN 54988) declared at Millstone Units 1, 2, and 3 due to seismic activity detected per abnormal operating procedures and evaluated Dominions response to the event on November 8, 2020.

Event Report (IP Section 03.02) (1 Sample)

The inspectors evaluated the following licensee event report (LER):

(1) License Event Report (LER) 05000336/2020-001-00, Failure of Two Main Steam Safety Valves to Lift Within the Technical Specification Acceptance Criteria (ADAMS Accession No. ML20234A417). The inspection conclusions associated with this LER are documented in this report under the Inspection Results section.

Reporting (IP Section 03.05) (2 Samples)

(1) The inspectors reviewed the circumstances surrounding a potential report issue involving an issue with the Unit 3 gaseous effluent radiation monitors on August 11, 2020
(2) The inspectors reviewed the circumstances surrounding a potential report issue involving an invalid actuation of the B train high head safety injection pump (3SIH*P1B), the B train low pressure safety injection pump (3RHS*P1B), and four steam generator blowdown containment isolation valves at Millstone Unit 3 on November 6,

INSPECTION RESULTS

Failure to Follow Seismic Housekeeping Requirements for Movable Carts, Ladders, Toolboxes and Filing Cabinets Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green [H.12] - Avoid 71111.04 Systems NCV 05000336,05000423/2020004-01 Complacency Open/Closed The inspectors identified a Green finding and associated non-cited violation (NCV) of 10 CFR Part 50, Appendix B, Criterion V, "Instructions, Procedures, and Drawings," when Dominion failed to follow the requirements of Station Procedure CM-AA-SHK-101, Seismic Housekeeping, Revision 6. Specifically, Dominion failed to secure multiple commodities located near seismically sensitive equipment in seismic housekeeping areas at both Unit 2 and Unit 3.

Description:

During routine plant status walkdowns of both Units 2 and 3, the inspectors identified five examples of improperly secured, movable commodities located near risk-significant, seismically sensitive permanent plant equipment in designated seismic housekeeping areas (e.g., control rooms, intake structures, auxiliary building). Several of the examples were located adjacent to protected equipment or in a protected equipment area. As described in licensee procedure OP-AA-600, protected equipment has been identified as essential for ensuring that safety functions and unit generation are maintained.

These commodities were not secured in accordance with Dominion procedure CM-AA-SHK-101, Seismic Housekeeping, Revision 6. Procedure CM-AA-SHK-101 establishes guidelines for reducing the risk to seismically sensitive equipment and systems from spatial interaction or impact from an adjacent commodity during a seismic event. Guidance is provided for the control of work in electrical cabinets, temporary items such as welding machines, test carts etc., and other movable equipment that could have a potential to damage safety-related components or systems in a seismic event.

The inspectors identified the following examples of improperly stored commodities:

  • On October 5, 2020, in the 3A EDG room, the NRC identified a stackable toolbox with a width of 20 inches and total height of 55 inches that was staged approximately 6 inches from safety-related electrical panel 3CES*PNLBD10 (electrical isolator cabinet). CM-AA-SHK-101 step 3.7.1.a does not permit stacking items and 3.4.2.d required a minimum distance of 61 inches from any seismically sensitive equipment.

The 3A EDG room was a protected equipment area at the time.

  • On October 13, 2020, in the 3B service water cubicle, NRC inspectors identified an unattended, standing ladder leaning against cable trays adjacent to a safety-related electrical isolator cabinet. The rope used to tie off the ladder was near the base of the ladder and was not tight enough to keep the ladder in place if it were jostled.

Step 3.11.4 of procedure CM-AA-SHK-101 required that unattended ladders left standing must be tied off at the top of the ladder and step 3.11.3 required the rope to be sufficiently taut to preclude movement. The 3B service water cubicle was a protected equipment area at the time.

  • On October 16, 2020, the inspectors identified an unattended, standing ladder improperly tied off in the 2B ESF room. The ladder was adjacent to the safety-related containment spray and residual heat removal pumps. The ladder was not tied off at the top as required by CM-AA-SHK-101 step 3.11.4. The 2B ESF room was a protected equipment area at the time.
  • On November 3, 2020, while Unit 3 was in Mode 5, the inspectors identified steel filing cabinets behind main boards 1, 2, and 3 that were not stored in accordance with CM-AA-SHK-101 and a deviation from the procedure had not been approved by site engineering personnel. These cabinets had been stored in this location for many years. Absent an approved deviation from the procedure, these cabinets met the definition of unstable commodity (step 5.3.7 of CM-AA-SHK-101) in that its height (60 inches) was more than twice the width and depth (14 inches wide and 29 inches deep). Step 3.6 of CM-AA-SHK-101 specified that the minimum distance between an unstable commodity and a seismically sensitive item is the height of the item plus 12 inches; therefore, these cabinets were required to be a minimum of 72 inches from the main boards, but they were approximately 49 inches away.

Note: On November 8, 2020, Millstone Units 2 and 3 declared an Unusual Event at 9:21 a.m.

EST after an earthquake was felt onsite. The earthquake monitoring instrumentation did not actuate, and there were no station system actuations. (EN54988)

  • On November 8 and November 9, 2020, the NRC inspectors performed walkdowns of both units to assess Dominions post-earthquake plant damage assessment. During these walkdowns, inspectors identified an improperly stored instrumentation and controls (I&C) cart in the Unit 3 instrument rack room (control room) and two carts improperly stored in the Unit 2 control room. Dominion failed to identify these seismic housekeeping issues in its post-earthquake walkdowns.

Corrective Actions: Dominion took prompt action to address each of these seismic housekeeping issues upon identification by the NRC inspectors. The commodities were

properly secured in accordance with procedure CM-AA-SHK-101 or removed from the area. In accordance with procedure CM-AA-SHK-101, Dominion completed an engineering evaluation of the steel filing cabinets behind the Unit 3 control room main boards and determined that they were seismically stable and were not a historical seismic concern.

Dominion also performed extensive, focused walkdowns to identify and correct seismic housekeeping issues.

Corrective Action References: CR1157261, CR1158214, CR1158554, CR1160013, CR1160632, CR1160634

Performance Assessment:

Performance Deficiency: Dominion's failure to follow Station Procedure CM-AA-SHK-101, Seismic Housekeeping, for commodities located near seismically sensitive equipment in five seismic housekeeping areas at both Unit 2 and Unit 3 was a performance deficiency.

Screening: The inspectors determined the performance deficiency was more than minor because if left uncorrected, it would have the potential to lead to a more significant safety concern. Specifically, the inspectors identified five commodities that were improperly stored near seismically sensitive equipment in the Unit 2 and Unit 3 control rooms, Unit 2 auxiliary building, Unit 3 EDG enclosure, and Unit 3 service water pumphouse. These commodities had the potential to roll, fall, overturn or otherwise impact safe shutdown equipment during a design basis seismic event.

Significance: The inspectors assessed the significance of the finding using Appendix A, The Significance Determination Process for Findings At-Power. The finding is of very low safety significance because it did not affect the design or qualification of a mitigating structure, system, or component, and did not involve the loss or degradation of equipment or PRA function specifically designed to mitigate a seismic, flooding, or severe weather initiating event for greater than 14 days.

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. The inspectors determined that multiple examples of failing to meet seismic housekeeping requirements at both units, demonstrated that individual contributors did not perform thorough reviews of the work site and planned activity every time work was performed, instead relying on past successes and assumed conditions. For example, plant workers failed to recognize these seismic housekeeping issues during rounds, while establishing protected equipment/area boundaries, and during post-earthquake plant damage assessments.

Enforcement:

Violation: 10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, states that activities affecting quality shall be prescribed by documented instructions, procedures, or drawings, of a type appropriate to the circumstances and shall be accomplished in accordance with these instructions, procedures, or drawings.

Section 2.6, Control of Activities, of DOM-QA-1, Nuclear Facility Quality Assurance Program, Revision 28, states "The Company has established administrative controls over activities for the nuclear facilities in accordance with the quality assurance program. These ensure that the applicable elements of 10 CFR 50, Appendix B are addressed during the performance of the activities. These programs include the appropriate use of qualified personnel,

procedures, and methods when performing the activities. They also address special controls necessary such as environmental conditions, cleanliness, housekeeping, use of special or calibrated equipment, and specific operating modes or conditions."

Procedure CM-AA-SHK-101, Seismic Housekeeping, Revision 6, states in part, "This procedure establishes guidelines for reducing the risk to seismically sensitive equipment and systems from spatial interaction or impact from an adjacent commodity during a seismic event. Guidance is provided for the control of work in electrical cabinets, temporary items such as welding machines, test carts etc., and other movable equipment that could have a potential to damage safety-related components or systems in a seismic event." Section 3.1, Applicability and Plant Seismic Housekeeping Areas, states that "The seismic housekeeping guidelines are to be used when temporary items are introduced into the stations. They are applicable to all commodities that may roll, fall, overturn, slide, or otherwise cause a hazardous effect or undesirable impact on seismically sensitive equipment in the event of an earthquake."

Contrary to the above, from October 5 to November 9, 2020, Dominion failed to accomplish prescribed activities affecting quality in accordance with the Millstone Seismic Housekeeping procedure, CM-AA-SHK-101, Revision 6, as evidenced by the following examples:

  • On October 5, 2020, in the 3A EDG room, the NRC identified an unstable toolbox within the minimum stand-off distance required by Section 3.4, Guidance for mobile commodity, and 3.7, Stacking of Commodities or Material, of CM-AA-SHK-101
  • On October 13, 2020, in the 3B service water cubicle, the NRC identified an unattended, standing ladder improperly tied off, which was contrary to section 3.11.3 and 3.11.4 of CM-AA-SHK-101
  • On October 16, 2020, in the 2B ESF room, the NRC identified an unattended, standing ladder improperly tied off, which was contrary to Section 3.11, Seismic Restraints, of CM-AA-SHK-101
  • On November 3, 2020, while Unit 3 was in Mode 5, the inspectors identified steel filing cabinets behind main boards 1, 2, and 3 that were not stored in accordance with CM-AA-SHK-101 and a deviation from the procedure had not been approved by site engineering personnel. Absent an approved deviation from the procedure, these cabinets met the definition of unstable commodity. These cabinets failed to meet the minimum stand-off distance required by Section 3.6, Guidance for Unstable Commodity, of CM-AA-SHK-101
  • On November 8 and November 9, 2020, the NRC inspectors identified an improperly stored I&C cart in the Unit 3 instrument rack room (control room) and two carts improperly stored in the Unit 2 control room. These carts were not stored in accordance with Section 3.4, Guidance for mobile commodity, of CM-AA-SHK-101 Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.

Failure to Control Transient Combustibles in Accordance with Fire Protection Program Procedure Cornerstone Significance Cross-Cutting Report Aspect Section Initiating Events Green [H.12] - Avoid 71111.05 NCV 05000423/2020004-02 Complacency Open/Closed The inspectors identified a Green finding and associated NCV of Millstone Unit 3 License Condition 2.H, Fire Protection, when Dominion failed to implement and maintain in effect all provisions of the approved Fire Protection Program. Specifically, on September 30, 2020, the inspectors identified eight, non-permitted, 275-gallon totes left unattended in the Unit 3 Auxiliary Building North Floor Area (Fire Area AB-1A), which was not in accordance with 1 of procedure CM-AA-FPA-101, Control of Combustible and Flammable Materials, and exceeded the limits provided by the fire severity calculation of record.

Description:

On September 30, 2020, the inspectors identified eight, non-permitted, 275-gallon totes left unattended in the Unit 3 Auxiliary Building North Floor Area (Fire Area AB-1A), which was contrary to Attachment 1 of procedure CM-AA-FPA-101, Control of Combustible and Flammable Materials, and exceeded the limits provided by the fire severity calculation of record. Attachment 1, Millstone Power Station Requirements, of CM-AA-FPA-101 states that combustibles and flammables may be stored only in areas approved by the site fire marshal either through site utilization [of] administrative procedures or by use of a fire prevention permit." The inspectors noted that the site fire marshal had not approved these transient combustibles. Upon further review, the inspectors noted that only 10 pounds of transient combustibles were provided for in the fire severity calculation (COMBLOAD-1325M3, Determination of Fire Severity for Fire Protection Report) for this fire area. Each tote weighed approximately 40 pounds; therefore, the as-found fire loading exceeded the fire hazard analysis limits.

Corrective Actions: Dominion promptly evaluated the temporary storage of the totes in this area and approved transient combustible permit (38445-20-FP) for ten 275-gallon totes.

Dominion also entered the issue in its corrective action program as CR1156765. Dominion reviewed the fire severity calculation, accounting for the additional transient combustible material, and determined that the equivalent fire severity for the area did not change.

Dominion also performed extent of condition walkdowns to identify and correct other non-permitted transient combustibles. Further corrective actions included an assessment of the station's process for submitting, tracking, and approving fire prevention permits.

Corrective Action References: CR1156765

Performance Assessment:

Performance Deficiency: The inspectors determined that the failure to implement the requirements of the fire protection procedures was a performance deficiency. Specifically, the failure to implement fire protection program procedures (CM-AA-FPA-101) for the control of transient combustibles was a failure to implement and maintain in effect all provisions of the approved fire Protection Program; therefore, a violation of License Condition 2.H, Fire Protection.

Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Protection Against External Factors attribute of the Initiating Events cornerstone and adversely affected the cornerstone objective to limit the

likelihood of events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. This finding was similar to example 4.j in Appendix E, Examples of Minor Issues, of IMC 0612, Power Reactor Inspection Reports," dated December 23, 2019. Specifically, the fire loading was not within the fire hazard analysis limits when approximately 320 pounds of non-permitted transient combustible materials were found in fire area AB-1A. The fire severity calculation (COMBLOAD-1325M3, Determination of Fire Severity for Fire Severity Protection Report) for fire area AB-1A was analyzed for only 10 pounds of transient combustibles.

Significance: The inspectors assessed the significance of the finding using Appendix F, Fire Protection and Post-Fire Safe Shutdown SDP. The inspectors determined that the safety significance of the finding was very low because based on the SDP qualitative screening question related to fire prevention and administrative controls, the finding did not increase the likelihood of a fire, delay detection of a fire, or result in the potential for a more significant fire than previously analyzed such that the credited safe shutdown strategy was adversely impacted.

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, individuals involved with storage of eight combustible totes in the Unit 3 Auxiliary Building, without a fire prevention permit, did not consider the undesired consequences of adding a significant amount of unanalyzed heat content to the fire area.

Enforcement:

Violation: License Condition 2.H, Fire Protection, to Facility Operating License NPF-49, requires the licensee to implement and maintain in effect all provisions of the approved Fire Protection Program as described in the Final Safety Analysis Report for the facility and as approved in the SER (NUREG-1031) issued July 1985 and Supplements Nos. 2, 4, and 5 issued September 1985, November 1985, and January 1986, respectively...

Section 3.5, Controlling the Use of Transient Combustibles, of Dominion procedure CM-AA-FPA-100, Fire Protection/Appendix R (Fire Safe Shutdown) Program, Revision 14, states that transient combustibles are controlled in accordance with CM-AA-FPA-101, Control of Combustible and Flammable Materials.

1 of CM-AA-FPA-101, "Control of Combustible and Flammable Materials,"

Revision 12, states that combustibles and flammables may be stored only in areas approved by the site fire marshal either through site utilization of administrative procedures or by use of a fire prevention permit."

Contrary to the above, on September 30, 2020, Dominion failed to implement and maintain in effect all provisions of the approved Fire Protection Program. Specifically, Dominion failed to implement procedure CM-AA-FPA-101 when eight, 275-gallon totes were stored in Fire Area AB-1A without the approval of the site fire marshal.

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 for Unit 2 High Range Vent Radiation 71114.05 Monitor Calibration Error This violation of very low safety significance was identified by Dominion and was entered into Dominions corrective action program and is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.

Violation: 10 CFR 50.54(q)(2) requires, in part, that a licensee shall follow and maintain the effectiveness of an emergency plan that meets the requirements in Appendix E to this Part and, for nuclear power reactor licensees, the planning standards of §50.47(b). 10 CFR 50.47(b)(4) requires, in part, that a standard emergency classification and action level (EAL)scheme is in use by Dominion.

Contrary to the above, from July 2006 to August 2020, Dominion had incorrect response factor settings programmed into the Unit 2 high range vent radiation monitor, RM8168, which would cause the monitor to read seven to nine times greater than actual levels. This had the potential to result in the declaration of a site area emergency before conditions warranted.

Significance: Green. The inspectors assessed the significance of the finding using IMC 0609, Appendix B. The inspectors determined that this finding was similar to the example in Table 5.4-1, Significance Examples §50.47(b)(4), which states the EAL classification process would result in an over-classification causing an unnecessary emergency declaration. Thus, the inspectors determined that the finding was of very low safety significance (Green).

Corrective Action References: CR 1153387 Licensee Identified Non-Cited Violation for Unit 3 Vent and Stack Gaseous 71124.05 Effluent Monitors Calibration Error This violation of very low safety significance was identified by Dominion and was entered into Dominions corrective action program and is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.

Violation: Millstone Unit 3 Technical Specification 6.8.1(h) states in part that written procedures shall be established, implemented, and maintained covering quality controls for effluent monitoring using the guidance in Regulatory Guide 1.21, Rev. 1, June 1974.

Regulatory Guide 1.21, Rev. 1, June 1974, Section C, Part 11(c) Calibrations states in part that individual written procedures should be prepared and utilized for specific methods of calibrating radiological monitoring systems and measuring equipment.

Contrary to the above, from June 2004 to August 2020, Dominion's individual written procedures did not contain appropriate specific methods for calibrating radiological monitoring systems. Specifically, Dominions individual written procedures for calibrating the Unit 3 vent and stack radioactive gaseous effluent monitors contained an erroneous value. The erroneous value was used for calculating the monitoring system efficiency for normal range detectors numbered 3HVR19B, 3HVR10B, and 3HVQ49. The error resulted in the monitors underestimating radioactive effluent gaseous releases from the plant vent and stack.

Significance: Green. The inspectors assessed the significance of the finding using IMC 0609, Appendix D, Public Radiation Safety Significance Determination Process. Dominion reassessed the dose to members of the public from the release of radioactive gaseous effluents and the dose impact was less than the dose values in Appendix I to 10 CFR Part 50 and 10 CFR 20.1301(e); therefore, the inspectors determined the significance to be Green.

Corrective Action References: CR 1153255 Observation: Unit 3 Emergency Diesel Generator Jacket Water Leaks 71152 The inspectors reviewed Millstones evaluation and corrective actions associated with 3A EDG JW leaks which occurred on January 18, 2017 (CR1058105) and February 6, 2019 (CR1115548). In both instances the leaks occurred on the JW return lines (right bank in 2017 and left bank return header in 2019) at a welded connection. In both instances operators declared the affected EDG inoperable.

Dominion staff completed apparent cause evaluation (ACE) CA4048581 and determined that the pipe leak in 2017 occurred due to fatigue induced cracking, which resulted from the weld joint configuration (i.e., partial joint penetration (PJP)) combined with the cyclic/vibratory nature of the engine while running). The welds were in the piping that is part of the EDG skid supplied components. As a result, these welds did not fall under the category of Class 1, 2, or 3 piping as defined in Section III of the ASME Boiler and Pressure Vessel (B&PV) code, which would have required the welds to be complete joint penetration (CJP) design.

Dominion staff repaired by grinding out the defect and rewelding per WO5310342702.

Additionally, Dominion staff planned a long-term corrective action (LTCA), scheduled to be completed in October 2020, to repair or replace Unit 3 EDG JW discharge elbow and turbocharger cooling piping PJP welds with CJP welds. The CJP weld was intended to eliminate the notch created at the root of the PJP groove welds and the associated stress riser at that location.

On February 6, 2019, Dominion staff identified a JW leak at a PJP weld in the 3A EDG left bank return header. Dominion entered the leak into their corrective action program and repaired the leak per WO53203239739. NRC inspectors previously reviewed these activities and documented a violation of very low safety significance related to inadequate corrective action scheduling in an NRC inspection report dated August 12, 2019 (ML19224B324).

In response to the second JW leak in 2019, Dominion staff completed a Level of Effort Evaluation (LEE) and concluded that the organization underestimated the probability of a subsequent leak, and as a result the LTCA weld repairs were not scheduled timely, nor was a bridging strategy considered. Dominion staff performed a bridging strategy corrective action by applying reinforcement welds to all welds on the JW skid mounted piping under WO53203240299 and WO53203240378 for 3A and B EDG, respectively. Additionally, Dominion staff conducted an extent of cause review for all open LTCAs from level 1 and 2 cause evaluations to validate they were scheduled utilizing the appropriate risk perception.

Dominion staff did not identify discrepancies from their review. Finally, as part of the LEE, Dominion staff reviewed mitigating system work orders with a risk ranking of 4 or higher to determine if risk had been addressed appropriately and if a bridging strategy should be implemented. Based on the review, Dominion staff adjusted some work order schedules associated with their mitigating system performance indictor with a risk ranking of 4 and higher.

On a sampling basis, the inspectors reviewed Dominions corrective actions and evaluations related to Unit 3 EDG JW weld leaks in 2017 and 2019. The inspectors reviewed weld repair documentation and documentation of replacement of PJP groove welds with CJP welds on skid mounted JW piping. The inspectors determined welds were designed and fabricated with quality commensurate with the safety significance. Specifically, Dominion utilized an ASME B&PV Section III CJP weld design as the replacement weld in leu of the original vendor design PJP weld. The inspectors questioned whether the replacement welds are subject to inservice inspections requirement such as ASME B&PV code Section XI. The inspectors determined that since the code class of the piping where the welds are located has not be reclassified and remains non-code as originally designed, ASME inservice inspection exams are not required. The inspectors observed Dominion performed a review of the problem for reportability and did not identify the issue was reportable under regulatory requirements.

Finally, the inspectors examined Dominion review of internal and industry operating experience related to EDG skid mounted weld leaks as well as vendor guidelines/

recommendations. The inspectors noted that 10 CFR Part 21 (1997-78) submitted by the EDG vendor, as well as an NRC Information Notice 98-43, informed the industry of PJP weld failures on EDG lube oil system piping. The inspectors questioned if the lube oil piping on Millstone Unit 3 EDGs contained vendor supplied PJP welds joints, and if so, were there plans to address the welds in a similar fashion as was done for JW welds. In response to the inspectors questions, Millstone staff stated that vendor PJP welds do exist in the lube oil piping of the Unit 3 EDGs but there are no plans to replace them because qualitatively they concluded the location, physical configuration, and size of the pipe is such that failure due to vibration induced fatigue is not a concern. The inspectors did not observe that there had been a record of lube oil leaks due to failure of a partial penetration weld on the vendor supplied skid mounted lube oil piping.

The inspectors concluded the LEE and corrective actions completed after the second JW leak in 2019 were of appropriate depth to identify likely causes and provide for corrective actions scheduled and completed commensurate with the safety significance of the problems.

Observation: Unit 2 Power Operated Relief Valve (PORV) Leakage 71152 The inspectors reviewed Dominions corrective actions performed following the identification of steam leakage past newly installed PORVs. In the fall 2018 outage Dominion replaced PORVs, installed in 2006, with new valves. The modification addressed steam leakage past the valve seats resulting in the valves being isolated during portions of operating cycles between 2008 and 2018. The new valves were of the same design as the valves installed in 2006 except that they were designed with flanged connections and bolted in place. The previous valves were welded to the piping. Dominion staff selected the flanged design to provide for removal of the entire valve in order to facilitate the performance of additional testing and maintenance. Following startup from the 2018 refueling outage, Dominion staff identified that one new valve leaked. Subsequently both valves began to leak and the PORVs were isolated by procedure via installed block valves. Dominion staff documented the problem in CR 1111536.

The inspectors determined Dominion staff performed a LEE (CA7464616) to identify the causes of the leakage and corrective actions to prevent recurrence. Dominion staff concluded that the preservice test acceptance criteria (no water droplets form on cold steel held at the discharge of the valve during the leak test) was not sufficient to ensure the valves were leak tight prior to installation. Dominion staff identified industry operating experience

that showed that more restrictive leak tightness acceptance criterion resulted in leak tight valves during operation. Dominion staffs corrective actions included developing new test acceptance criteria based on the operating experience in order to verify the valves were leak tight prior to installation. Specifically, Dominion staff changed their leak testing procedure acceptance criteria to no condensation present on a cold steel bar held at the discharge of the closed valve during the leak test. Dominion staff also completed additional actions including contracting with a different test facility to perform the testing. In 2020 the valves were removed from the plant and sent to the test facility for overhaul and tested to the new limits. Subsequently the valves were reinstalled in the plant and have been leak tight during the current operating cycle.

The inspectors reviewed the LEE, revised test procedures, and valve testing results; and determined that Dominions performance to evaluate the causes of the leakage and the corrective actions taken adequately identified the probable causes of leakage from the PORVs and corrective actions have successfully stopped leakage from the valves.

Observation: Troubleshooting Plans - Semiannual Trend Review 71152 The inspectors reviewed a sample of troubleshooting plans and associated condition reports for equipment issues at both Unit 2 and Unit 3 to determine whether plant equipment issues that required troubleshooting were indicative of an adverse trend or more significant safety issue. The inspectors also reviewed these troubleshooting activities to determine whether Dominion adequately implemented procedure MA-AA-103, Conduct of Troubleshooting, Revision 16. The inspectors determined that the issues investigated under the sample of troubleshooting plans were appropriately evaluated by Dominion staff for potential trends through entry into the corrective action program and were appropriately resolved within the scope of the corrective action program. The inspectors also determined that the sample of troubleshooting plans were developed and implemented in accordance with procedure MA-AA-103.

Main Steam Safety Relief Valve Lift Setpoint Exceeds Technical Specification Allowable Value, Closure of LER 05000336/2020-001-00, Failure of Two Main Steam Safety Valves to Lift Within the Technical Specification Acceptance Criteria Cornerstone Severity Cross-Cutting Report Aspect Section Not Severity Level IV Not 71153 Applicable NCV 05000336/2020004-03 Applicable Open/Closed A self-revealed Severity Level IV NCV of Technical Specification (TS) 3.7.1.1 was identified when Dominion discovered, through as-found surveillance testing, that two main steam safety relief valves (MSSVs) had lift pressure setpoints that were not within TS lift setting tolerance.

Description:

With the plant in MODE 1 at 100 percent rated thermal power on April 21 and April 22, 2020, set pressure testing of all Unit 2 MSSVs was conducted per plant procedures.

Two of the sixteen valves did not meet the as-found acceptance criteria of +/- 3 percent within setpoint. The failures of the two valves, 2-MS-242 and 2-MS-245, were consistent in that both valves lifted more than 3 percent above the setpoint.

TS Table 4.7-1 allows a +/- 3 percent setpoint tolerance (allowable value) on the as-found lift setting, to account for drift over an operating cycle. During this testing, the MSSVs are OPERABLE provided that the actual as-found lift settings are within +/- 3 percent of the required lift setting. A footnote to Table 4.7-1 required that the lift setting be within +/-1

percent of the required lift setting following testing (as-left).

The as-found lift pressures for the two valves exceeded the +/- 3 percent TS allowable values and were therefore inoperable. The test result for 2-MS-242 was 3.3 percent above the nameplate set pressure of 990.3 psig, or 2.3 psi outside of the acceptance range. The test result for 2-MS-245 was 3.3 percent above the nameplate set pressure of 1000.3 psig, or 2.9 psi outside of the acceptance range. Dominion promptly declared each valve inoperable and the valves were retested without adjustment until each had two successive tests with results meeting the required set pressure "as-left" test acceptance criteria of +/- 1 percent. 2-MS-242 was tested two additional times following the "as-found" test, without adjustment, and the two consecutive tests were within the required "as-left" +/- 1 percent criteria. 2-MS-245 was tested three additional times following the "as-found" test, without adjustment, and the last two consecutive tests were within the required "as-left" +/- 1 percent criteria. Based on two successive, acceptable as-left tests, Dominion declared both valves operable.

There was no inservice test program test scope expansion required because testing was planned to be performed on all 16 MSSVs. The other 14 MSSVs were tested and all as-found lift settings were found to be within +/- 3 percent of their set pressures.

Because a similar discrepancy in multiple valves is an indication that the discrepancies may have occurred at some point during the operating cycle and were therefore likely inoperable for greater that the TS allowed outage time of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, this condition was reportable under 10 CFR 50.73(a)(2)(i)(B), "any operation or condition prohibited by the plant's technical specifications." The NRC previously documented that Dominion failed to submit this licensee event report within 60 days from discovery of an existing, but previously unrecognized, condition prohibited by the plant's TSs (NCV 05000336/2020002-01, ML20225A010).

Corrective Actions: The failure of the MSSVs to meet the as-found, TS acceptance criteria was documented in CR 1145274.

Corrective Action References: CR 1145274

Performance Assessment:

The NRC determined this violation was not reasonably foreseeable and preventable by Dominion and therefore is not a performance deficiency.

Enforcement:

Enforcement Policy Section 2.2.4 states, in part, that violations with no associated performance deficiency will be dispositioned using traditional enforcement."

Because no performance deficiency was identified, this violation is assessed using traditional enforcement.

Severity: The inspectors reviewed the NRC Enforcement Policy, Section 2.2.1, Factors Affecting Assessment of Violations, issued on January 15, 2020. Section 2.2.1 states, in part, that in determining the appropriate enforcement response to a violation, the NRC considers, whenever possible, risk information in assessing the safety or security significance of violations and assigning severity levels.

The NRC determined the issue to be more than minor because the issue affected multiple MSSVs and a detailed engineering analysis was required to determine the significance of the issue.

The inspectors also reviewed IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power, Exhibit 2, Mitigating Systems Screening Questions, effective December 20, 2019. The inspectors determined the issue to be of very low safety

significance because it did not represent a deficiency affecting the design or qualification of a mitigating SSC nor did it represent a loss of the PRA function of one or more systems or functions (All questions in Exhibit 2 - Mitigating Systems Screening Questions, of IMC 0609 Appendix A were answered "No"). Also, Dominion's engineering evaluation determined that based on the "as-found" test results both valves would have lifted prior to reaching the updated final safety analysis report design limit of 1085.3 psig, and would have reliably performed their design function of protecting the main steam system.

Accordingly, after considering that the condition represented very low safety significance, the inspectors concluded that the violation would be best characterized as Severity Level IV under the traditional enforcement process.

Violation: TS 3.7.1.1 Limiting Condition for Operation states, All main steam line code safety valves shall be operable with lift settings as specified in Table 4.7-1. With one or more main steam line code safety valves per steam generator inoperable, the TS Condition 3.7.1.1.a Required Action is to reduce thermal power within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to less than or equal to the applicable percent of rather thermal power in Table 3.7-1, and reduce the power level-high trip setpoint in accordance with Table 3.7-1 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. Otherwise, be in hot standby within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and hot shutdown within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

Contrary to the above, during operating cycle 26 (2018 to 2020) Millstone Unit 2 operated with two inoperable MSSVs and failed to take the action required by TS 3.7.1.1. Similar discrepancies in two (multiple) valves is an indication that the discrepancies may have arisen over a period of time; therefore, it is reasonable to conclude the condition existed during cycle 26 plant operation.

Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.

EXIT MEETINGS AND DEBRIEFS

The inspectors verified no proprietary information was retained or documented in this report.

  • On January 14, 2021, the inspectors presented the integrated inspection results to Mr. John Daugherty, Site Vice President and other members of Dominion staff.
  • On October 1, 2020, the inspectors presented the Emergency Preparedness Program Inspection results to John Daugherty, Site Vice President and other members of Dominion staff.
  • On December 15, 2020, the inspectors presented the Unit 3 EDG jacket water weld failures problem identification and resolution annual sample inspection results to William Watson, System Engineer Supervisor and other members of Dominion staff.

THIRD PARTY REVIEWS Inspectors reviewed Institute on Nuclear Power Operations report that was issued during the inspection period.

DOCUMENTS REVIEWED

Inspection Type Designation Description or Title Revision or

Procedure Date

71111.01 Procedures C OP 200.13 Seasonal Weather Operations Revision 17

C OP 200.13-002 Unit 2 Cold Weather Preparation Checklist Revision 5

C OP 200.13-002 Unit 2 Cold Weather Checklist Revision 17

C OP 200.13-003 Unit 3 Cold Weather Preparation Checklist Revision 1

Work Orders 53203257955 Unit 2 Cold Weather Preparation Revision 0

71111.04 Corrective Action 1157261

Documents 1158214

Resulting from 1158554

Inspection 1160013

1160632

1160634

Drawings 25212-26930 Piping & Instrumentation Diagram Feedwater System Revision 49

212-26930 Piping & Instrumentation Diagram Feedwater System Revision 28

Work Orders 53103012744 12R Valve Overhaul M33FWA*V014

53103012750 12R Valve Overhaul M33FWA*V023

71111.05 Corrective Action 1156765

Documents 1158319

Resulting from

Inspection

71111.11Q Procedures MP-PROC-OPS- Abnormal Operating Procedure Instrument Failure Response

AOP 3571

MP-PROC-OPS- Plant Startup Revision 29

OP 3203

MP-PROC-OPS- Pressurizer Pressure Control Revision 12-

OP 3301G 03

MP-PROC-OPS- Main Turbine Revision 23

OP 3323A

MP-PROC-OPS- Annunciator System Main Board 4 RPI Non-Urgent Failure Revision 21

OP 3353

MP-PROC-OPS- Turbine Generator Testing (ICCE) Revision 30

SP 3623.1

71111.12 Self-Assessments PIR1140869 Maintenance Rule (MR) (a)(3) periodic assessment for the Revision 0

Inspection Type Designation Description or Title Revision or

Procedure Date

period of 07/01/2018 to 12/31/2019

71111.13 Corrective Action 1158217

Documents 1158554

Resulting from

Inspection

71111.18 Corrective Action 1158433

Documents

Engineering MP3-20-01179 Unit 3 EDG Fuel Rack Roll Pin Replacement Revision 0

Changes

Work Orders 53102451531 STELLITE 21 Wedge Guide Replacement - DC MP3-19- Revision 0

01143

71111.19 Corrective Action 1158217

Documents

Resulting from

Inspection

Engineering MP3-19-01143 Cobalt Alloy Hardfacing of 3RHS*MV8701B Valve Wedge Revision 0

Changes Guide Surfaces

Work Orders 53203294582 Perform inspections for cause of no rotation 10/02/2020

203296144 Spool 3SWP-003-324-3 through-wall leak on "B" SW Strainer Revision 0

Common Blowdown Line

203296144 Spool 3SWP-003-324-3 through-wall leak on "B" SW strainer Revision 0

common blowdown line

71111.22 Procedures MA-MP-BDB-101 Semi-Annual or Annual Test of Flex Equipment Revision 6

SP 2610BO TDAFP Tests, Operating Revision 9

SP 3608.6 Safety Injection System Valve Operability Test Revision 17

SP 3622.3 Auxiliary Feedwater Pump 3FWA*P2 Operational Readiness Revision 34

Test

71114.02 Miscellaneous Dominion Millstone Alert and Notification System Upgrade Revision 0

Project FEMA REP-10 Design Report Addendum

Procedures MP-26-EPA- Alert Notification System Test and Maintenance Revision 10

FAP09

71114.03 Miscellaneous Millstone Power Emergency Plan Revision 20

Procedures MP-26-EPA- Management Program for Maintaining Emergency Revision 17

FAP01 Preparedness

Inspection Type Designation Description or Title Revision or

Procedure Date

71114.05 Miscellaneous KLD TR-1132 Millstone Power Station 2019 Population Update Analysis 12/06/2019

71124.05 Corrective Action 1153255 08/11/2020

Documents

71152 Corrective Action 1058105 01/19/2017

Documents 1058155 01/19/2017

1111536

1115548 02/06/2019

1118242 03/14/2019

1118631 03/19/2019

1160848

Corrective Action 1157261

Documents 1158214

Resulting from 1161118

Inspection

Drawings 25212-39241 Lube Oil System Schematic Emergency Diesel Generator 12/28/2007

SH.9

212-39241, Welded Piping 14 CYL. PC7V Skid ASME III CL. 3 01/09/2009

SH.150

Engineering ETE-MP-2019- Acceptable Jacket Water Leak Rates for the Unit 3 Emergency 10/22/2019

Evaluations 1080 Diesel Generators

Miscellaneous 25212-241-001 Vendor Technical Manual, Installation, Operation and Revision 1

Maintenance of Emergency Diesel Engine

Procedures LI-AA-301 Implementation of 10 CFR Part 21, Reporting of Defects and Revision 2

Noncompliance

NWS-T-143 NWS Technologies Test Procedure for Dominion - Millstone Revision 2

2, Target Rock Power Operated Relief Valves (PORV)

Operability Testing

Work Orders 53103042702 Weld Repairs on Jacket Cooling Piping 01/31/2017

53103113782 M33EGS*EGA Replace Left and Right Bank Jacket Water 08/31/2020

Discharge Pipe. CA 3050575

53103113783 M33EGS*EGB, EC MP3-20-01014, Replace Diesel Jacket 06/15/2020

Water Discharge Piping CA3050576

203239739 M33EGS*EGA Jacket Water Leak Repair (LH ELBOW) 02/06/2019

203240299 M33EGS*EGA Weld Reinforcement on Upper Jacket Water 03/05/2019

Inspection Type Designation Description or Title Revision or

Procedure Date

Piping

203240378 M33EGS*EGB Weld Reinforcement on Upper Jacket Water 03/18/2019

Piping

71153 Corrective Action CA7899914

Documents

Procedures AOP 3570 Abnormal Operating Procedure - Earthquake Revision 17

29

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