IR 05000336/2022002

Integrated Inspection Report 05000336/2022002 and 05000423/2022002

ML22223A033
Person / Time
Site:	Millstone
Issue date:	08/11/2022
From:	Matt Young NRC/RGN-I/DORS
To:	Stoddard D Dominion Energy
Young M
References
IR 2022002
Download: ML22223A033 (33)

Text

August 11, 2022

SUBJECT:

MILLSTONE POWER STATION, UNITS 2 AND 3 - INTEGRATED INSPECTION REPORT 05000336/2022002 AND 05000423/2022002

Dear Daniel Stoddard:

On June 30, 2022, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Millstone Power Station, Units 2 and 3. On July 21, 2022, the NRC inspectors discussed the results of this inspection with Michael O'Connor, Site Vice President, 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. Two Severity Level IV violations without an associated finding are documented in this report. We are treating these violations as non-cited violations (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, Digitally signed by Matthew R.

Matthew R. Young Date: 2022.08.11 09:41:27 Young -04'00'

Matt R. Young, Chief Projects Branch 2 Division of Operating Reactor Safety 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: 05000336/2022002 and 05000423/2022002 Enterprise Identifier: I-2022-002-0037 Licensee: Dominion Energy Nuclear Connecticut, Inc.

Facility: Millstone Power Station, Units 2 and 3 Location: Waterford, CT 06385 Inspection Dates: April 1, 2022, to June 30, 2022 Inspectors: J. Fuller, Senior Resident Inspector E. Allen, Resident Inspector E. Bousquet, Resident Inspector J. Brand, Reactor Inspector P. Cataldo, Senior Reactor Inspector L. Cline, Senior Project Engineer B. Edwards, Health Physicist A. Turilin, Reactor Inspector S. Wilson, Senior Health Physicist Approved By: Matt R. Young, Chief Projects Branch 2 Division of Operating Reactor Safety Enclosure

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees 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.

List of Findings and Violations

Inaccurate Information Provided to the NRC in Unit 3 License Amendment Request to Extend Integrated Leak Rate Test Intervals Cornerstone Severity Cross-Cutting Report Aspect Section Not Applicable Severity Level IV Not Applicable 71111.08P NCV 05000423/2022002-01 Open/Closed The NRC inspectors identified a Severity Level IV non-cited violation (NCV) of Title 10 of the Code of Federal Regulations (CFR) 50.9, Completeness and Accuracy of Information, because the licensee provided inaccurate information in a license amendment request submitted to the NRC, to extend the containment integrated leak rate test intervals. In the request, the licensee incorrectly stated that they had performed general, visual examinations of the containment leak chase channels under the Millstone Unit 3 containment inservice inspection program (also referred to as the IWE program), but the inspectors determined that only 14 of the 38 leak chase channel panels had been examined under the IWE program.

Unit 3 Main Steam Safety Valves Installed in the Wrong Locations Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green [H.12] - Avoid 71153 Systems NCV 05000423/2022002-02 Complacency Open/Closed A finding of very low safety significance (Green) and an associated NCV of 10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, was self-revealed on April 5, 2022, when as-found surveillance testing revealed that two main steam safety valves (MSSVs) had lift pressure setpoints outside of Technical Specification (TS) 3.7.1.1 limits.

Unit 2 Reactor Building Closed Cooling Water Train Not Operable Greater than Technical Specification Allowed Outage Time Cornerstone Severity Cross-Cutting Report Aspect Section Not Applicable Severity Level IV Not Applicable 71153 NCV 05000336/2022002-03 Open/Closed A Severity Level IV NCV of TS 3.7.3.1 was self-revealed when Dominion discovered that one loop of the reactor building closed cooling water (RBCCW) system did not have structural integrity and was not operable for longer than the TS allowed outage time.

Additional Tracking Items

Type Issue Number Title Report Section Status LER 05000336/2022-001-00 LER 2022-001-00 for 71153 Closed Millstone, Unit 2, Structural Integrity of Reactor Building Component Cooling Water Cracked Threaded Fitting Could Not Be Established Resulting in System Inoperable Longer Than Allowed by Technical Specifications LER 05000423/2022-001-00 LER 2022-001-00 for 71153 Closed Millstone, Unit 3, Emergency Core Cooling and Reactor Plant Component Cooling Water Systems Inoperable for Time Greater Than Allowed by Technical Specifications LER 05000423/2022-002-00 LER 2022-002-00 for 71153 Closed Millstone, Unit 3, Two Main Steam Safety Valves Installed in Wrong Location Resulting in Failure to Lift within the Technical Specification Acceptance Criteria URI 05000423/2022001-01 Unit 3 Charging Pump and 71153 Closed Component Cooling Water Pump Area Exhaust Fan (3HVR*FN13B) Bearing Failure

PLANT STATUS

Unit 2 operated at or near rated thermal power for the entire inspection period.

Unit 3 began the inspection period at rated thermal power. On April 7, 2022, the unit was shut down for a planned refueling outage. The unit was returned to rated thermal power on June 10, 2022, and remained at or near rated thermal power for the remainder of the inspection period.

INSPECTION SCOPES

Inspections were conducted using the appropriate portions of the inspection procedures (IPs) in effect at the beginning of the inspection unless otherwise noted. Currently approved IPs with their attached revision histories are located on the public website at http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/index.html. Samples were declared complete when the IP requirements most appropriate to the inspection activity were met consistent with Inspection Manual Chapter (IMC) 2515, Light-Water Reactor Inspection Program - Operations Phase. The inspectors performed activities described in IMC 2515, Appendix D, Plant Status, conducted routine reviews using IP 71152, Problem Identification and Resolution, observed risk-significant activities, and completed on-site portions of IPs. The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel to assess licensee performance and compliance with Commission rules and regulations, license conditions, site procedures, and standards.

71111.04 - Equipment Alignment

Partial Walkdown (IP Section 03.01) (6 Samples)

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

(1) Unit 3 pressurizer, reactor coolant system instrumentation and temporary connections for decreased inventory on April 14, 2022

(2) Unit 3 control room emergency ventilation system and control room envelope boundary during core offload on April 17, 2022

(3) Unit 3 spent fuel pool cooling and purification on April 19, 2022

(4) Unit 3 electrical alignment of the station blackout diesel to the 'B' residual heat removal system on May 4, 2022

(5) Unit 3 'A' residual heat removal system and backup power supply, 'A' emergency diesel generator (EDG), while in Mode 6 during reactor coolant system drain on May 4, 2022

(6) Unit 2 refueling water storage tank (M2T41), instrumentation, associated piping, and valves external to the auxiliary building on June 22, 2022

Complete Walkdown (IP Section 03.02) (2 Samples)

(1) The inspectors evaluated system configurations during a complete walkdown of the Unit 3 containment recirculation system including accessible portions of the heat exchangers, pumps, spray piping, associated valves, and piping on April 26, 2022.

(2) The inspectors evaluated system configurations during a complete walkdown of the Unit 3 charging pump cooling system including new heat exchangers, along with control valves, pumps, and piping on June 30, 2022

71111.05 - Fire Protection

Fire Area Walkdown and Inspection (IP Section 03.01) (7 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 3 engineered safety features building, southeast floor area, auxiliary feed pump cubicle, 4'-6"and 21'-6" elevations (fire area ESF-5), following a failed fire damper inspection on April 6, 2022

(2) Unit 2 'A' safeguards pump room (fire area A-8A) following the failure of safeguards room to main exhaust (2-HV-322) on April 13, 2022

(3) Unit 2 steam-driven auxiliary feed pump pit (fire area T-4) on April 26, 2022

(4) Unit 2 west 480V load center room (fire area T-6) on May 10, 2022

(5) Unit 3 containment structure (fire area RC-1) and compensatory actions following a fire header rupture between April 11 and May 19, 2022

(6) Unit 3 service building north and south cable tunnels, 4'-6" elevation (fire areas SB-2 and SB-3), on June 13, 2022

(7) Unit 2 reactor coolant pump rebuild shop preparation room (fire area A-29) and diesel oil-day tank room A and B (fire areas A-30 and A-31) on June 17, 2022

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) Flood compartment ESF-1 (south containment recirculation cooler cubicle - 34'-9" through 36'-6" elevations) and ESF-2 (north containment recirculation cooler cubicle -

34'-9" through 36'-6" elevations) on June 30, 2022

(2) Unit 2 'A' EDG vault on the 14'-6" elevation on June 30, 2022

71111.07T - Heat Exchanger/Sink Performance Heat Exchanger (Service Water Cooled) (IP Section 03.02)

The inspectors evaluated heat exchanger performance on the following:

(1) Unit 3 charging pump cooling heat exchanger, CCE-HTX-1A, Section 03.02, cooled by service water

Heat Exchanger (Closed Loop) (IP Section 03.03) (1 Sample)

The inspectors evaluated heat exchanger performance on the following:

(1) Unit 3 residual heat removal heat exchanger A (RHR-HTX-1A), Section 03.03, cooled by reactor plant component cooling water (RPCCW)

Ultimate Heat Sink (IP Section 03.04) (1 Sample)

(1) Unit 2 ultimate heat sink, Section 03.04 (b), (c), (d), (e), and Unit 3 service water strainers, Section 03.04 (b), (c), (d), and (e)

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

(1) The inspectors verified that the reactor coolant system boundary, steam generator tubes, reactor vessel internals, risk-significant piping system boundaries, and containment boundary were appropriately monitored for degradation and that repairs and replacements were appropriately fabricated, examined, and accepted by reviewing the following activities from April 11 to June 6, 2022:

03.01.a - Nondestructive Examination (NDE) and Welding Activities

• Manual ultrasonic testing of the pressurizer safety nozzle to head vent at 147 Az. 12, UT-03-007-SW-B (NDE Report M3-UT-22-016)

• Manual ultrasonic testing of the crossover leg elbow-to-pipe, RCS-LP1-FW-7 (NDE Report M3-UT-22-020)

• Visual examination of containment floor leak chase channel panels and associated moisture barrier 03.01.b - Pressurized-Water Reactor Vessel Upper Head Penetration Examination Activities

• Bare metal visual examination of penetrations 18, 42, 43, 46, 50, and 66 (NDE Report 3-VE-22-001)03.01.c - Pressurized-Water Reactor Boric Acid Corrosion Control Activities

• Boric acid evaluation for M33RCS*V140, reactor coolant Loop 4 fill isolation valve (CR1196059)

• Boric acid evaluation for M33SSR*V800, reactor coolant hot leg sample line leakage monitoring connection/vent (CR1196211)

• Boric acid leak repair work order for M33RCS*V996, Loop 4 TC sample isolation valve (CR1196064)

• Boric acid leak repair work for M33RCS*P1B reactor coolant pump seal (CR1196088)03.01.d - Pressurized-Water Reactor Steam Generator Tube Examination Activities

• Eddy current examinations of tubes in all four steam generators (S/G A, B, C, and D)

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 Unit 2 control room during 'C' service water surveillances, 'C' high pressure safety injection surveillances, and reactivity manipulations. The inspectors observed annunciator alarm response and functionality assessment of the stack radiation monitor (8169) on May 17, 2022.

(2) The inspectors observed and evaluated licensed operator performance in the Unit 3 control room during plant cooldown and reactor coolant system solid plant pressure control on April 8, 2022, and hot rod drop testing on May 20, 2022.

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

(1) The inspectors observed and evaluated Unit 3 simulator startup just-in-time training on May 12, 2022.

(2) The inspectors observed and evaluated operator performance in the Unit 2 simulator involving turbine trip, reactor trip, loss of reactor coolant accident, and declaration of a site area emergency due to loss of onsite emergency power sources on June 14, 2022.

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) Unit 3 maintenance preventable functional failure evaluation of the 'B' train charging pump and RPCCW pump area exhaust fan (3HVR*FN13B) which failed on January 23, 2022 (CR1189837 and CA10834269)

(2) Unit 3 loss of pressurizer level indication during draining of the 'C' reactor coolant system loop while in Mode 5 on April 10, 2022 (CR1196240)

Quality Control (IP Section 03.02) (1 Sample)

The inspectors evaluated the effectiveness of maintenance and quality control activities to ensure the following SSC remains capable of performing its intended function:

(1) Storage and verification of quality parts for the Unit 3 EDG (WO53203338009), 'C' main steam isolation valve (WO53102632302), and battery 3 (301A-2)

(WO53103131606) during maintenance on April 6 and June 16, 2022 (CR1195619)

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management (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 3 increased risk during reactor coolant system solid plant pressure control, an infrequently conducted or complex evolution, on April 8, 2022

(2) Unit 3 elevated risk during decreased reactor coolant system inventory and high decay heat from April 11 to 13, 2022

(3) Unit 2 risk mitigating actions during turbine driven auxiliary feedwater pump surveillance testing on April 26, 2022

(4) Unit 3 risk assessment and associated mitigating actions associated with draining the reactor coolant system while the 'B' EDG was out of service, which is an infrequently conducted or complex evolution, and verification of 'A' train protections on May 4, 2022

(5) Unit 2 elevated risk of a loss of the south 345kV bus during planned work in the switchyard on May 23, 2022

(6) Unit 2 elevated reactor trip risk while 15G-8T-2 breaker was out of service for sulfur hexafluoride (SF6) gas addition on June 1, 2022

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment (IP Section 03.01) (7 Samples)

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

(1) Unit 3 functionality evaluation of electric fire pump after it failed to start on April 11, 2022

(2) Unit 3 'A' and 'B' EDG operability evaluation after discovery of metal shavings (CR1196957) and a wooden wedge (CR1197076) in the 'B' EDG gear housing during maintenance on April 19, 2022

(3) Unit 2 noble gas effluent monitor (high range) (RM-8168) operability assessment (CR1198444) on May 16, 2022

(4) Unit 2 TS 4.0.3 entered due to missed low pressure safety injection pump comprehensive test because of out-of-tolerance measuring and test equipment (CR1188877, CR1190815, and CR1191694) on June 10, 2022

(5) Unit 2 'B' EDG operability assessment due to an air leak from the starting air solenoid (2-DG-95B) (CR1192032) on June 14, 2022

(6) Unit 3 operational decision making for a degraded seal on the 'A' reactor coolant pump (CR1199799, CR1199909, and CA11176629) on June 30, 2022

(7) MP3 'C' RPCCW pump outboard bubbler leakage exceeding 30-day mission time limit (CR1202467) on June 30, 2022

71111.18 - Plant Modifications

Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02)

(3 Samples)

The inspectors evaluated the following temporary or permanent modifications:

(1) Unit 3 permanent modification of 'B' EDG (M33EGS*EGB) voltage regulator on April 26, 2022 (WO53203267888)

(2) Unit 3 permanent modification to replace steam generator number 2 (3RCS*SG1B)narrow range channel IV level transmitter (M33FWS*LT527) at the end of qualified life on April 28, 2022 (WO53102388383)

(3) Unit 3 permanent modification to turbine driven auxiliary feed water pump steam supply valve room air conditioning unit on June 30, 2022 (WO53203289628)

71111.19 - Post-Maintenance Testing

Post-Maintenance Test (IP Section 03.01) (8 Samples)

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

(1) Unit 3 battery 4 (M3301B-2) after battery cell replacement on April 22, 2022 (WO53203157124)

(2) Unit 3 'B' EDG (M33EGS*EGB) following the voltage regulator replacement on April 26, 2022 (WO53203338009)

(3) Unit 3 supplementary leak collection and release system (SLCRS) drawdown test after repairs were made to the 'B' train of the SLCRS dampers 3HVV*MOD51C and 3HVR*AOD35A on May 17, 2022 (WO53203300072 and WO53203345112)

(4) Unit 3 'C' main steam isolation valve (3MSS*CTV27C) after solenoid valve and block replacement on June 1, 2022 (WO53102632302)

(5) Unit 2 pressurizer proportional heaters capacity test following the calibration of proportional heater controller on June 13, 2022 (WO53203356709)

(6) Unit 2 'B' EDG operability test and 'B' train starting air inservice test following the air start solenoid (M22DG-95B) replacement on June 23, 2022 (WO53203341686)

(7) Unit 2 'B' EDG after replacement of the start failure relay block on June 28, 2022 (WO53203357480 and CR1202185)

(8) Unit 2 west DC switchgear cooling fan (M2F54B) following the replacement of the fan belt on June 29, 2022 (WO53203357736)

71111.20 - Refueling and Other Outage Activities

Refueling/Other Outage (IP Section 03.01) (1 Sample)

(1) The inspectors evaluated Millstone Unit 3 refueling outage 3R21 from April 7 to June 4, 2022.

71111.22 - Surveillance Testing

The inspectors evaluated the following surveillance testing activities to verify system operability and/or functionality:

Surveillance Tests (other) (IP Section 03.01) (7 Samples)

(1) Unit 3 'B' train of the SLCRS, which failed the building drawdown surveillance on April 6, 2022 (SP 3614I.3 and CR1195831)

(2) Unit 3 MSSV surveillance testing on April 7, 2022 (WO53203297542)

(3) Unit 3 supplemental position verification of 3RCS*AV8145 (pressurizer auxiliary spray valve) on April 8, 2022 (SP 3604A.5-028)

(4) Unit 2 containment gaseous and particulate process radiation monitor (RM 8262)functional test on April 22, 2022

(5) Unit 2 turbine driven auxiliary feedwater pump surveillance testing on April 26, 2022 (SP 2610BO-001, -002, -004, and -005)

(6) Unit 2 facility 1 engineered safeguards actuation system under voltage, reserve station transformer and sequencer calibration, and functional test on May 2, 2022 (WO53203328194)

(7) Unit 2 refuel water storage tank level functional test on May 2, 2022 (WO53203328191)

Inservice Testing (IP Section 03.01) (3 Samples)

(1) Unit 2 service water pump 'A' (P-5A) quarterly inservice test on April 10, 2022 (WO53203321083)

(2) Unit 2 'A' high pressure safety injection pump and check valve inservice testing on May 6, 2022 (SP 2604AO and WO53203329995)

(3) Unit 3 turbine driven auxiliary feedwater pump operational readiness and quarterly inservice test on June 29, 2022 (WO53203320030)

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

(1) Unit 3 chilled water valve 3CDS*CTV39A local leak rate test surveillance on May 3, 2022 (WO53203246488)

FLEX Testing (IP Section 03.02) (1 Sample)

(1) Semiannual testing of MP-BDB-P2B and MP-BDB-P2C (auxiliary feedwater pumps) beyond design basis FLEX equipment on June 29, 2022 (WO53203335609)

71114.06 - Drill Evaluation

Drill/Training Evolution Observation (IP Section 03.02) (1 Sample)

The inspectors evaluated:

(1) Performance indicator drill for Units 2 and 3 with an event classification, notification, and protective action recommendations from the technical support center on April 27,

71124.01 - Radiological Hazard Assessment and Exposure Controls

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

(1) The inspectors evaluated how the licensee identifies the magnitude and extent of radiation levels and the concentrations and quantities of radioactive materials and how the licensee assesses radiological hazards.

Instructions to Workers (IP Section 03.02) (1 Sample)

(1) The inspectors evaluated how the licensee instructs workers on plant-related radiological hazards and the radiation protection requirements intended to protect workers from those hazards.

Contamination and Radioactive Material Control (IP Section 03.03) (3 Samples)

The inspectors observed/evaluated the following licensee processes for monitoring and controlling contamination and radioactive material:

(1) Radiological surveys of potentially contaminated material leaving the radiologically controlled area at Unit 3

(2) Workers exiting the radiologically controlled area at Unit 3 during a refueling outage

(3) Common to Units 2 and 3; control of potentially contaminated groundwater samples

Radiological Hazards Control and Work Coverage (IP Section 03.04) (4 Samples)

The inspectors evaluated the licensee's control of radiological hazards for the following radiological work:

(1) Unit 3 outage reactor disassembly phase I radiation work permit and grayloc disassembly and reassembly TEDE as low as reasonably achievable (ALARA)evaluation - radiation work permit number 3220301

(2) Unit 3 outage steam generator primary eddy current testing ALARA Plan - plan number AP-3-22-05

(3) Unit 3 outage valve inspection and maintenance ALARA Plan - plan number AP-3-22-10

(4) Unit 3 outage scaffold assemble, modify, and disassemble ALARA Plan - plan number AP-3-22-11 High Radiation Area and Very High Radiation Area Controls (IP Section 03.05) (4 Samples)

The inspectors evaluated licensee controls of the following high radiation areas and very high radiation areas:

(1) Units 2 and 3 high radiation area key control for all high radiation, locked high radiation, and very high radiation areas

(2) Unit 3 containment in-core detector tubes very high radiation area controls

(3) Unit 3 containment regenerative heat exchanger room locked high radiation area controls

(4) Unit 3 refuel cavity locked high radiation area controls 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.

71124.06 - Radioactive Gaseous and Liquid Effluent Treatment

Walkdowns and Observations (IP Section 03.01) (4 Samples)

The inspectors evaluated the following radioactive effluent systems during walkdowns:

(1) Unit 3 SLCRS B-train filter room

(2) Unit 3 auxiliary building 66' ventilation system intake and exhaust

(3) Unit 3 auxiliary building rooftop ventilation ductwork

(4) Unit 2 spent fuel pool ventilation and radiation monitor

Sampling and Analysis (IP Section 03.02) (3 Samples)

Inspectors evaluated the following effluent samples, sampling processes, and compensatory samples:

(1) Observed Unit 3 REI-19 A & B gaseous effluent samplers

(2) Observed charcoal cartridge exchange and analysis for Unit 3 HVQ-49 gaseous effluent sampler

(3) Observed particulate filter exchange and analysis for Unit 3 HVQ-49 gaseous effluent sampler

OTHER ACTIVITIES - BASELINE

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

IE01: Unplanned Scrams per 7000 Critical Hours (IP Section 02.01) ===

(1) Unit 2 (April 1, 2021, through March 31, 2022)

(2) Unit 3 (April 1, 2021, through March 31, 2022)

IE03: Unplanned Power Changes per 7000 Critical Hours (IP Section 02.02) (2 Samples)

(1) Unit 2 (April 1, 2021, through March 31, 2022)

(2) Unit 3 (April 1, 2021, through March 31, 2022)

IE04: Unplanned Scrams with Complications (IP Section 02.03) (2 Samples)

(1) Unit 2 (April 1, 2021, through March 31, 2022)

(2) Unit 3 (April 1, 2021, through March 31, 2022)

71152A - Annual Follow-up Problem Identification and Resolution Annual Follow-up of Selected Issues (Section 03.03)

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

(1) Unit 2 'A' EDG unexpectedly tripped during a slow start surveillance on January 5, 2022 (CR1188991)

(2) Unit 3 failure of chilled water supply header containment isolation valve (CDS*CTV38A) to perform its safety function to close during surveillance testing on April 12, 2022 (CR1196420)

71153 - Follow Up of Events and Notices of Enforcement Discretion Event Report (IP Section 03.02)

The inspectors evaluated the following licensee event reports (LERs):

(1) LER 05000336/2022-001-00 for Millstone, Unit 2, Structural Integrity of Reactor Building Component Cooling Water Cracked Threaded Fitting Could Not Be Established Resulting in System Inoperable Longer Than Allowed by Technical Specifications (Agencywide Documents Access and Management System (ADAMS)

Accession No. ML22081A025): The inspection conclusions associated with this LER are documented in this report under the Inspection Results Section, SLIV NCV

===05000336/2022002-03.

(2) LER 05000423/2022-001-00 for Millstone, Unit 3, Emergency Core Cooling and Reactor Plant Component Cooling Water Systems Inoperable for Time Greater Than Allowed by Technical Specifications (ADAMS Accession No. ML22088A024): The inspection conclusions associated with this LER are documented in this report under the Inspection Results Section, URI 05000423/2022001-01.

(3) LER 05000423/2022-002-00 for Millstone, Unit 3, Two Main Steam Safety Valves Installed in Wrong Location Resulting in Failure to Lift within the Technical Specification Acceptance Criteria (ADAMS Accession No. ML22151A121): The inspection conclusions associated with this LER are documented in this report under the Inspection Results Section, NCV 05000423/2022002-02.

Notice of Enforcement Discretion (NOED) (IP Section 03.04) ===

(1) The inspectors evaluated the licensee actions for Unit 3 surrounding NOED EA-22-008 which can be accessed at http://www.nrc.gov/reading-rm/doc-collections/enforcement/notices/noedreactor.html, on May 16, 2022. The inspectors completed Sections 03.04.c and 03.04.d of IP 71153. Completion of Sections 03.04.a and 03.04.b of the IP were documented in Millstone Power Station, Units 2 and 3 -

Integrated Inspection Report 05000336/2022001 and 05000423/2022001 (ADAMS Accession No. ML22130A518).

INSPECTION RESULTS

Inaccurate Information Provided to the NRC in Unit 3 License Amendment Request to Extend Integrated Leak Rate Test Intervals Cornerstone Severity Cross-Cutting Report Aspect Section Not Severity Level IV Not 71111.08P Applicable NCV 05000423/2022002-01 Applicable Open/Closed The NRC inspectors identified a Severity Level IV NCV of 10 CFR 50.9, Completeness and Accuracy of Information, because the licensee provided inaccurate information in a license amendment request submitted to the NRC, to extend the containment integrated leak rate test intervals. In the request, the licensee incorrectly stated that they had performed general, visual examinations of the containment leak chase channels under the Millstone Unit 3 containment inservice inspection program (also referred to as the IWE program), but the inspectors determined that only 14 of the 38 leak chase channel panels had been examined under the IWE program.

Description:

The inspectors followed up on an issue previously described in NRC Integrated Inspection Report for the Millstone Power Station dated February 10, 2022 (ADAMS Accession No. ML22041A419) that involved an NCV for inaccurate information related to a Millstone Unit 2 license amendment request. A similar license amendment request was made for Millstone Unit 3 by letter dated July 30, 2019 (ADAMS Accession No. ML19217A208),where the licensee requested the Millstone Unit 3 containment integrated leak rate test intervals be extended. The Millstone Unit 3 license amendment request stated that:

Previously, the Millstone IWE Program had inspected the accessible leak chase channels and plugs or caps during the general visual examination as a liner boundary. In response to NRC Information Notice 2014-07, Degradation of Leak Chase Channel System for Floor Welds of Metal Containment Shell and Containment Metallic Liner, the examination was expanded to include an inspection under E-A Containment Surfaces, Item No. E130 -

Moisture Barriers. This examination identified no deficiencies. At this time there are no primary containment surface areas that require augmented examinations in accordance with

[American Society of Mechanical Engineers] ASME Section XI, IWE-1240.

The NRC approved this request for Millstone Unit 3 by issuing Amendment No. 276 (ADAMS Accession No. ML20161A000) dated July 15, 2020.

The inspectors observed licensee actions onsite the week of April 11 through 21, 2022, to walkdown Millstone Unit 3 leak chase locations to ensure the Millstone Unit 3 ASME, Section XI, IWE inspection program accurately reflected the in-plant configuration. This was a corrective action from the Millstone Unit 2 related NCV. During accompaniment of licensee staff completing this activity, the inspectors inquired as to the drawings and/or documentation the licensee was using to ensure all the leak chase channels were identified and examined.

Based on inspectors questions during the walkdown, licensee staff recovered original construction drawings indicating the approximate location of all leak chase channel test panels. As a result of inspectors' questions and extent of condition walkdowns, the inspectors identified that licensee staff did not perform the general visual examinations of all accessible leak chase channel moisture barrier locations (i.e., plugs or caps), as intended. Specifically, a significant number of the moisture barrier leak chase channel test panel locations, 24 out of 38, were identified to not have been examined in previous walkdowns as part of the Millstone Unit 3 ASME, Section XI, IWE inspection program. The inspectors determined the statement provided in the license amendment request was inaccurate and constituted a violation of 10 CFR 50.9, Completeness and Accuracy of Information.

Upon visual examination during the refueling outage in April 2022, licensee staff determined the leak chase moisture barrier was intact and capable of performing its function.

Corrective Actions: The licensee generated CR1197174 to address this discrepancy.

Corrective Action References: CR1197174

Performance Assessment:

The inspectors determined this violation was associated with a minor performance deficiency.

Enforcement:

The ROPs significance determination process does not specifically consider the regulatory process impact in its assessment of licensee performance. Therefore, it is necessary to address this violation which impedes the NRCs ability to regulate using traditional enforcement to adequately deter non-compliance.

Severity: The inspectors determined this is a Severity Level IV violation in accordance with Section 6.9 of the NRC Enforcement Policy. In particular, the inspectors considered that, had the information been complete and accurate at the time, it likely would have resulted in the need for further clarification of the licensees actions to address NRC Information Notice 2014-07 but would not have caused the NRC to change the decision to issue the license amendment or resulted in substantial further inquiry.

Violation: 10 CFR 50.9, Completeness and Accuracy of Information, states, in part, that information provided to the Commission by a licensee shall be complete and accurate in all material respects.

Contrary to the above, on July 30, 2019, the licensee failed to ensure that information provided to the NRC was complete and accurate in all material respects associated with a license amendment request to extend the containment integrated leak rate test intervals required by TS 6.8.4.f, Containment Leakage Rate Testing Program. Specifically, the licensee stated ...the Millstone IWE Program had inspected the accessible leak chase channels and plugs or caps during the general visual examination as a liner boundary... the examination was expanded to include an inspection under E-A Containment Surfaces, Item No. E1.30 - Moisture Barriers. This examination identified no deficiencies. However, although the program included examining leak chase channels under Category E-A, Item No. E1.11 and Item No. E1.30, the licensee historically only examined 14 out of a total of 38 leak chase channel panels at Millstone Unit 3. This information was material to the NRC because it was considered as part of the basis for approving a license amendment request to extend containment integrated leak rate test intervals.

Enforcement Action: This violation is being treated as an NCV, consistent with Section 2.3.2 of the Enforcement Policy.

Observation: CR1188991 - Unit 2 'A' Emergency Diesel Generator Unexpectedly 71152A Tripped During a Slow Start Surveillance on January 5, 2022 During a slow start surveillance on January 5, 2022, the Unit 2 'A' EDG unexpectedly tripped. The Unit 2 'A' EDG was inoperable and unavailable for maintenance rule and required an unplanned entry into the applicable TS action statement.

The inspectors reviewed the licensees causal evaluation, Information Notice 93-96 regarding EDG fuel rack resets, applicable revisions of the EDG surveillance testing and operating procedures, documented EDG operator recollections for recent Unit 2 EDG fuel rack resets, and Dominion human performance standards and guidance.

Licensee troubleshooting immediately following the trip ruled out the engine and generator electronic trips as the cause of the engine trip. Using a Why Staircase in its causal evaluation, the licensee determined that the direct cause of the engine trip was a mechanical trip of the engine fuel racks but did not identify a probable cause for the mechanical trip of the fuel racks.

The licensees Why Staircase identified the following potential causes for a mechanical trip of the fuel racks: an overspeed condition, a local manual trip push button actuation or inadequate latching of the fuel racks due to trip mechanism wear, and sluggish operation of the emergency stop push button reset spring or human performance errors during the fuel rack reset after completion of a pre-lube and air roll surveillance on December 12, 2021.

However, the licensee also determined that each of these potential causes was either not credible or not probable based on additional investigation.

The licensee determined that no actual overspeed condition existed based on its review of available engine indications immediately prior to the trip and confirmed that at the time of the trip no operators were in the vicinity of the local manual trip push button. Then, licensee field inspections of the fuel rack trip mechanism and the engine mounted emergency stop button eliminated mechanism surface wear and a push button sluggish spring as probable causes.

Finally, licensee discussions with the operators who reset the engine on December 12, 2021, coupled with licensee observations of operator performance during subsequent fuel rack resets and licensee comparisons of operating experience to site procedures, did not identify human performance errors during engine reset as a likely cause. Therefore, the licensee did not identify a probable cause for the mechanical trip of the Unit 2 'A' EDG on January 5, 2022.

In response to the indeterminate causal evaluation, the licensee enhanced the pre-lube and air roll surveillance procedure by adding more detail to the fuel rack reset procedure steps to increase the likelihood of a successful latch of the engine shutdown mechanism.

The inspectors independently observed performance of a Unit 2 EDG fuel rack reset after a subsequent pre-lube and air roll surveillance to confirm procedure compliance and adequate use of human performance tools. The inspectors also confirmed the procedure enhancement revisions proposed in the licensee causal evaluation were completed and made effective in early March 2022.

No Unit 2 EDG fuel rack reset issues have occurred during or after the monthly pre-lube and air rolls surveillances performed on either Unit 2 EDG since the January 2022 engine trip.

The inspectors also noted that the trip mechanisms for Unit 3 EDGs are not like those on Unit 2.

No findings or violations were identified.

Unit 3 Main Steam Safety Valves Installed in the Wrong Locations Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green [H.12] - Avoid 71153 Systems NCV 05000423/2022002-02 Complacency Open/Closed A finding of very low safety significance (Green) and an associated NCV of 10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, was self-revealed on April 5, 2022, when as-found surveillance testing revealed that two MSSVs had lift pressure setpoints outside of TS 3.7.1.1 limits.

Description:

In Modes 1, 2, and 3, limiting condition of operation (LCO) 3.7.1.1 requires that all main steam line code safety valves shall be OPERABLE with lift setting as specified by table 3.7-3.

On April 5 and 6, 2022, with the plant in MODE 1 at 90 percent power, lift setting testing of the Millstone Power Station Unit 3 (MPS3) MSSVs was conducted per plant procedure SP 3712G, Main Steam Code Safety Valve Surveillance Testing. Two of the 20 valves did not meet the as found acceptance criteria of +/-3 percent of the required setpoint. The MSSV from the 'B' steam generator, 3MSS*RV22B, lifted above the maximum lift setting and the MSSV from the 'D' steam generator, 3MSS*RV26D, lifted below the minimum lift setting as specified in MPS3 TS Table 3.7-3, Steam Line Safety Valves Per Loop.

The two MSSVs were adjusted, retested, and declared operable before proceeding with remaining valve tests. Both valves were returned to operable status by two successive tests with results within +/-1 percent of the set pressure.

Valve 3MSS*RV26D is one of five MSSVs with staggered setpoints for the D steam generator. Valve 3MSS*RV22B is one of five MSSVs with staggered setpoints for the B steam generator. The licensees cause evaluation determined that plant workers failed to verify the MSSV setpoints for valves 3MSS*RV22B and 3MSS*RV26D as required by step 50 in WO53M30502431 and WO53M30502419.

The primary purpose of the main steam line code safety valves is to provide overpressure protection for the secondary system. The MSSVs also provide protection against over pressurizing the reactor coolant pressure boundary by providing a heat sink for the removal of energy from the reactor coolant system if the preferred heat sink, provided by the condenser and circulating water system, is not available. The MSSV design includes staggered setpoints, according to table 3.7-3 in the accompanying LCO, so that only the needed valves will actuate. Staggered setpoints reduce the potential for valve chattering that is due to steam pressure insufficient to fully open all valves following a turbine reactor trip.

Table 3.7-3 allows a 3 percent setpoint tolerance (allowable value) on the lift setting for OPERABILITY to account for drift over an operating cycle.

Both 3MSS*RV26D and 3MSS*RV22B were replaced during the previous refueling outage in October 2020, and this was the first time they were tested since installation. A review of the completed installation work orders for the valve replacements revealed that the wrong safety valve with the wrong lift setting was installed in these two valve locations. The licensee determined that the set point for the two replacement safety valves was correctly set at the vendor using the lift setting listed on its nameplate; but due to a human performance error, licensee staff had installed the two valves in the wrong locations. Specifically, during the task preview step for these work orders, the licensee did not verify the selected valves setpoint pressure prior to installation. This resulted in a safety valve with a lift setting of 1225 psig, being installed in the 3MSS*RV22B location, and a safety valve with a lift setting of 1185 psig being installed in the 3MSS*RV26D location. The 3MSS*RV22B location was supposed to receive a safety valve with a lift setting of 1185 psig, and the 3MSS*RV26D location was supposed to receive a safety valve with a lift setting of 1225 psig. Therefore, the 'B' steam generator operated with two safety valves with a set pressure of 1225 psig, and the 'D' steam generator operated with two safety valves with a set pressure of 1185 psig.

The UFSAR, Section 10.3, function for the main steam safeties is preventing steam pressure from exceeding 110 percent of the main steam system design pressure of 1185 psig. The licensee determined that although the valves were installed in the wrong locations, the system safety function was maintained. Both setpoint settings were outside the +/-3 percent acceptance criteria for the lift setpoint, however, the licensees engineering analysis concluded that the expected high pressure using these setpoints would remain below the maximum pressure limit described in the UFSAR.

Because this discrepancy in two valves were greater than 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 plants technical specifications. The licensee submitted LER 05000423/2022-002-00, Two Main Steam Safety Valves Installed in Wrong Location Resulting in Failure to Lift Within the Technical Specification Acceptance Criteria, on May 31, 2022.

Corrective Actions: Upon discovery of the MSSVs failure to meet the as-found, TS acceptance criteria, during surveillance testing the MSSVs were adjusted and tested two times successfully to restore to OPERABLE. This was documented in CR1195703, CR1195780, and CR1195912. A causal evaluation was performed, and corrective actions were taken to add quality control verification of set pressure and human performance enhancements in MSSV work orders.

Corrective Action References: CR1195703, CR1195780, CR1195912

Performance Assessment:

Performance Deficiency: The licensee failed to perform the work order procedure step to verify replacement valve lift setpoint for two MSSVs during installation of 3MSS*RV22B and 3MSS*RV26D as required by WO53M30502419 and WO53M30502431. The inspectors determined that the failure to install MSSVs in accordance with associated procedures was contrary to 10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings.

Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Configuration Control 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. Failure to install the MSSVs in the correct location resulted in a failure to meet TS 3.7.1.1.

Significance: The inspectors assessed the significance of the finding using IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power. The inspectors determined the violation to be of very low safety significance because the finding did not affect the design or qualification of a mitigating SSC and did not represent the loss of the probabilistic risk assessment (PRA) function of the system.

Cross-Cutting Aspect: H.12 - Avoid Complacency: Individuals recognize and plan for the possibility of mistakes, latent issues, and inherent risk, even while expecting successful outcomes. Individuals implement appropriate error reduction tools. Specifically, the licensee failed to verify the setpoint pressure during the task preview prior to installation of the MSSVs 3MSS*RV22B and 3MSS*RV26D.

Enforcement:

Violation: 10 CFR Part 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, states in part, 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.

Step 50 of WO53M30502431 and WO53M30502419 stated VERIFY replacement valve setpoint is 1185 PSIG [WO53M30502419] VERIFY replacement valve setpoint is 1225 PSIG (WO53M30502431].

Contrary to the above, on October 12 and 13, 2020, the licensee did not accomplish an activity affecting quality in accordance with documented instructions appropriate to the circumstances. Specifically, the licensee did not verify the MSSV setpoints for valves 3MSS*RV22B and 3MSS*RV26D as prescribed by step 50 in WO53M30502431 and WO53M30502419. This resulted in a failure to meet TS 3.7.1.1 from October 12, 2020, to April 6, 2022.

The disposition of this violation closes LER 05000423/2022-002-00, "Two Main Steam Safety Valves Installed in Wrong Location Resulting in Failure to Lift within the Technical Specification Acceptance Criteria.

Enforcement Action: This violation is being treated as an NCV, consistent with Section 2.3.2 of the Enforcement Policy.

Unit 2 Reactor Building Closed Cooling Water Train Not Operable Greater than Technical Specification Allowed Outage Time Cornerstone Severity Cross- Report Cutting Section Aspect Not Severity Level IV Not 71153 Applicable NCV 05000336/2022002-03 Applicable Open/Closed A Severity Level IV NCV of TS 3.7.3.1 was self-revealed when Dominion discovered that one loop of the RBCCW system did not have structural integrity and was not operable for longer than the TS allowed outage time.

Description:

A leak in the RBCCW system was self-revealed on December 28, 2021, with Millstone Unit 2 in Mode 1 at 100 percent power, when an increase in containment sump level was correlated to increased RBCCW system leakage. The licensee created CR1188454 and promptly began to search for the leak location. Using a remote-controlled crawler, the leak was determined to be in the 'C' reactor coolant pump motor area on January 19, 2022. Following further containment entry and inspection, on January 20, 2022, at 7:00 p.m., the Technical Requirements Manual (TRM) 3.4.10 action for structural integrity was entered when the leak location was narrowed down to the ASME Class III, 3/4-inch RBCCW piping supplying the 'C' reactor coolant pump motor lower bearing cooler. The leak rate was approximately 0.185 gpm, which was less than the allowable external leakage limit for the RBCCW system of 0.60 gpm. The unit was shut down on January 22, 2022, to allow closer inspection to identify and evaluate the specific leak location within the TRM 3.4.10 allowed action time. While in Mode 3, on January 22, 2022, the point of leakage was identified at a threaded fitting on the RBCCW 3/4-inch line supplying the 'C' reactor coolant pump lower bearing cooler. After removal, the inlet pipe stub-end that threads into the bearing cooler was observed to be cracked internal to the pipe diameter. Engineering determined that structural integrity could not be established as there was no approved method to evaluate a threaded joint for structural integrity. Cooldown continued and Mode 4 was entered at 4:32 p.m. on January 22, 2022, and Mode 5 was entered at 3:30 a.m. on January 23, 2022. On January 24, 2022, leak repairs and retests were completed.

The lower bearing oil cooler pipe for the reactor coolant pump motor is supplied to Millstone Station pre-assembled for installation. The licensee determined that the cause of this cracked pipe was lack of complete thread engagement during assembly at the vendor. The inlet and outlet RBCCW piping for the reactor coolant pump lower bearing oil coolers are not disassembled or reassembled at Millstone. The vendor completes the motor overhaul, and the vendor does not typically remove this piping during motor overhaul activities; therefore, it is unknown when this fitting was last worked on or directly inspected. The location of the cracked piping was not easily accessible or visible during reactor coolant pump motor installation.

TS 3.7.3.1 requires that two RBCCW loops shall be operable in Modes 1-4. The licensee determined that the leak existed in December 2021 and structural integrity was likely lost at that time. In accordance with TRM 3.4.10, Structural Integrity, if structural integrity cannot be maintained, the licensee must isolate the affected component and if it cannot be isolated within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, the affected component must be declared non-functional. For this leak, one loop of RBCCW was inoperable for longer than its 72-hour allowed outage time. This was a condition reportable pursuant to 10 CFR 50.73(a)(2)(i)(B), an operation or condition prohibited by TSs. The licensee submitted LER 05000336/2022-001-00, Structural Integrity of Reactor Building Component Cooling Water Cracked Threaded Fitting Could Not Be Established Resulting in System Inoperable Longer Than Allowed by Technical Specifications, on March 18, 2022.

The inspectors reviewed this LER and related cause evaluation documented in level of effort evaluation (LEE CA9206748). The inspectors determined that the lack of full thread engagement was not reasonably within the licensee's ability to foresee or correct and that the licensee's actions to identify and correct the leak once it was recognized were timely and appropriate. Therefore, the inspectors did not identify a performance deficiency associated with this TS violation.

Corrective Actions: After finding the crack, new lower bearing RBCCW inlet and outlet piping was fabricated and installed on the C reactor coolant pump. After replacing the RBCCW piping, an extent of condition was performed on A, B, and D reactor coolant pumps and no leaks were observed. The inlet and outlet pipe stubs for the C reactor coolant pump were removed and sent to Dominion Energy Services Nuclear Engineering Materials Lab to be tested to support the investigation. The licensee created corrective action assignments to review quality assurance oversight of this vendor and create work orders to replace similar piping for the other reactor coolant system pumps during the next refueling outage.

Furthermore, the licensee revised its procedure to ensure that the correct thread engagement is present for the inlet and outlet piping going into the lower bearing oil cooler.

Corrective Action References: CR1188454, CR1188959, CR1189881

Performance Assessment:

The NRC determined this violation was not reasonably foreseeable and preventable by the licensee 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 14, 2022. 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 degraded condition affecting the 'A' safety loop of RBCCW if left uncorrected could have the potential to lead to a more significant safety concern.

The inspectors, with support from a regional senior reactor analyst (SRA), determined the degraded condition affected both the support system initiator Initiating Events and Mitigating System cornerstones. The SRA evaluated the issue using IMC 0609, Appendix A, The Significance Determination Process for Findings At-Power, Exhibit 1, Initiating Events Screening Questions, effective January 1, 2021, and determined the degraded condition would not increase the likelihood of a complete loss of a support system that would result in a plant trip and would screen to Green (Question C.2), or very low risk safety significance. The condition was further evaluated under Exhibit 2, Mitigating System Screening Questions, and determined a detailed risk evaluation was appropriate because the degraded condition represented a loss of the PRA function of one train of a multi-train TS system for greater than the TS allowed outage time (Question A.3).

The SRA, using NRCs SAPHIRE 8.2.6 and Millstone Unit 2 model 8.71, evaluated the increase in risk for internal events and seismic (bin 1) for a bounding 25-day exposure time. The SRA assumed a 10x increase in loop 'A' RBCCW failure probabilities. Total risk increase was assessed to be of very low safety significance and dominated by the failure of

'B' loop RBCCW. Considering both the initiating event and mitigating system aspects, the SRA assessed this represents a relatively inappreciable potential safety significance increase and is consistent with characterizing the TS violations as Severity Level IV.

Violation: The structural integrity of ASME Code Class 1, 2, and 3 components shall be maintained in accordance with Technical Surveillance Requirement 4.4.10. Millstone Unit 2 TS 3.7.3.1 requires that while the plant is in Modes 1, 2, 3, or 4, two RBCCW loops shall be OPERABLE. The TS ACTION statement requires that, with one RBCCW loop inoperable, restore the inoperable loop to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in COLD SHUTDOWN within the next 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.

Contrary to the above, between December 28, 2021, and January 22, 2022, one RBCCW loop was inoperable because structural integrity of an ASME Class III component in the loop was not maintained, and the licensee did not take action to either restore the loop to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in cold shutdown within the next 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.

The disposition of this violation closes LER 05000336/2022-001-00, Structural Integrity of Reactor Building Component Cooling Water Cracked Threaded Fitting Could Not Be Established Resulting in System Inoperable Longer Than Allowed by Technical Specifications.

Enforcement Action: This violation is being treated as an NCV, consistent with Section 2.3.2 of the Enforcement Policy.

URI Unit 3 Charging Pump and Component Cooling Water 71153 Pump Area Exhaust Fan (3HVR*FN13B) Bearing Failure URI 05000423/2022001-01

Description:

On January 23, 2022, at 11:18 a.m., the ventilation exhaust fan (3HVR*FN13B)for the charging pumps and RPCCW pumps area within the auxiliary building tripped at Unit 3. The operating crew entered EOP 3509, Fire Emergency, LCO 3.5.2 Emergency Core Cooling Systems, and LCO 3.7.3 Reactor Plant Component Cooling Water System.

During the subsequent troubleshooting and repair activities, technicians found that the motor shaft had bent, causing the fan blades to contact the housing. Due to the extent of damage, the motor and fan blade assembly were replaced. As corrective maintenance progressed, restoration of the ventilation system was forecasted to extend beyond the original TS 72-hour allowed outage time.

On January 26, 2022, at 8:30 a.m., the licensee orally requested that an NOED be issued.

The enforcement discretion period requested to be effective for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> past the TS 3.5.3 and TS 3.7.3 LCO action statement expirations, i.e., until January 29, 2022, at 11:18 a.m.

The NRC granted the NOED on January 26, 2022 (ADAMS Accession No. ML22034A674).

On January 27, 2022, at 8:50 p.m., the licensee exited the LCOs for TS 3.5.2 and TS 3.7.3.

As a result, the NOED terminated at 8:50 p.m. on January 27, 2022, within the period of the enforcement discretion.

The inspectors performed an assessment of the adequacy of licensee corrective actions and cause determinations and evaluated whether the cause for the need to request an NOED was the result of a violation or a failure to meet a licensee self-imposed standard.

The inspectors noted that the function of fan 3HVR*FN13B is to maintain the temperature of the charging pump and RPCCW area within the TS limits. The inspectors also noted that prior to this failure, the licensee was aware that a bearing failure would place the unit in a 72-hour shutdown action statement, which was not long enough to perform a bearing replacement should one be needed. In 2010, the licensee extended the bearing replacement preventive maintenance from once every 12 years to once every 15 years. The bearing was purchased commercial grade and dedicated as a basic component in 2007. The bearing was placed in service in April 2007 and performed satisfactorily until it failed on January 23, 2022 (13.9 years of service).

The bearings installed in fan 3HVR*FN13B motor are a double shielded type with a replacement strategy based on projected run hours coupled with periodic vibration monitoring. These bearings were last replaced on April 29, 2007, under WO53M30604011.

The fan motor was scheduled to be overhauled, including bearing replacement, under WO53102255098 with a targeted start date of 3R21 (April 10, 2022). There were no preventive maintenance tasks associated with checking or replenishing the bearing grease as they are shielded and are lubricated for the life of the bearing.

The inspectors noted that the bearing failed before its expected service life and that prior to discovery of the fan trip on January 23, 2022, Unit 3 had not experienced any alarms or other abnormal conditions which would indicate that a failure of 3HVR*FN13B was imminent.

Moreover, Unit 3 had not experienced any previous occurrences where the 72-hour allowed outage time for one inoperable charging pump and RPCCW pump was challenged because of a failure of an exhaust fan.

The licensee's cause evaluation stated that the direct cause was bearing failure and the apparent cause was that the bearing provided and installed in 2007 was inadequately greased when it was supplied. The licensee initiated corrective actions to change the motor overhaul (bearing replacement) back to a 12-year frequency, update maintenance procedures to pack the bearing house with additional grease, and investigate the use of improved vibration monitoring tools for these types of fans.

Based on the circumstances surrounding this premature failure of the bearing, the inspectors determined that this issue was not reasonably within the licensee's ability to foresee and prevent; therefore, there was no performance deficiency associated with this TS violation for which the NRC granted enforcement discretion.

This inspection closes URI 05000423/2022001-01, Unit 3 Charging Pump and Component Cooling Water Pump Area Exhaust Fan (3HVR*FN13B) Bearing Failure, and LER 05000423/2022-001-00, Emergency Core Cooling and Reactor Plant Component Cooling Water Systems Inoperable for Time Greater Than Allowed by Technical Specifications.

Corrective Action References: CR1189937, CR1190090, LEE

EXIT MEETINGS AND DEBRIEFS

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

• On April 14, 2022, the inspectors presented the radiation protection inspection results to Michael O'Conner, Site Vice President, and other members of the licensee staff.

• On April 21, 2022, the inspectors presented the Unit 3 inservice preliminary inspection results to Michael O'Connor, Site Vice President, and other members of the licensee staff.

• On June 16, 2022, the inspectors presented the Units 2 and 3 triennial heat sink inspection results to Michael O'Connor, Site Vice President, and other members of the licensee staff.

• On June 23, 2022, the inspectors presented the Unit 3 inservice final inspection results to Michael O'Connor, Site Vice President, and other members of the licensee staff.

• On July 21, 2022, the inspectors presented the integrated inspection results to Michael O'Connor, Site Vice President, and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection Type Designation Description or Title Revision or

Procedure Date

71111.04 Corrective Action CRX407279

Documents CR1127911

CR1180645

CR1202519

CR552171

Drawings 25203-26015 Piping and Instrumentation Diagram High Pressure Safety Revision 51

Injection Pumps, Sheet 2

212-26902 Piping and Instrumentation Diagram Reactor Coolant Revision 30

System, Sheet 3

212-26951 Piping and Instrumentation Diagram Control Building Revision 33

Heating, Ventilation and Air Conditioning, Sheet 1

212-26951 Piping and Instrumentation Diagram Control Building Revision 23

Heating, Ventilation and Air Conditioning, Sheet 2

212-26951 Piping and Instrumentation Diagram Control Building Revision 17

Heating, Ventilation and Air Conditioning, Sheet 3

Procedures ARP 2590E-125 RWST Pipeway Sump Level Hi/Lo CA-23 Revision 0

Work Orders 53103019028

203319259

71111.05 Calculations COMBLOAD-1325M3 Revision 1

Corrective Action CR1195241

Documents CR1195317

CR1195599

CR1196015

CR1196517

CR1199309

Engineering ETE-MP-2020- Combustible Loading Transient Calculation Tool Revision 0

Evaluations 1125

Procedures CM-AA-FPA-101 Control of Combustible and Flammable Materials Revision 15

MP-CALC-ENG- Calculation No. EPM-186 Millstone Nuclear Power Plant Revision 2

EPM 186 Unit 2

MP-PROC-ENG- MPS2 Fire Fighting Strategies, E & W 480V Load Centers Revision 3

U2-24-FFS-

BAP01-480V

MP-PROC-ENG- Control Building Fire Strategy Map Revision 5

U2-24-FFS-

BAP01-CB-Map

MP-PROC-ENG- MPS3 Fire Fighting Strategies Control Building Revision 3

U3-24-FFS-

BAP01-CB

MP-PROC-ENG- Fire Fighting Strategy Revision 1

U3-24-FFS-

BAP01-ESF

MP-PROC-ENG- MP3 Fire Fighting Strategies Containment Structure Revision 0

U3-24-FFS-

BAP01-RC

SFP 17 Fire Penetration Seal and Barrier Inspections Revision 4

71111.06 Corrective Action CR1189155

Documents

Drawings 25203-20146 SH-1024 Air Water Tight Wall Auxiliary Building Floor 12/24/2013

203-24107 Warehouse Aux. Bldg. & Containment Encl. Bldg. El. 14'-6" Revision 14

Barrier Boundaries

203-51384 Diesel Generator A & B Room Vestibule Water Barrier Revision 1

Miscellaneous NOTEBK-PRA- MPS2 PRA Model Notebook Internal Flooding - Flood

MPS2-IF.2 Scenario Development

71111.08P Corrective Action 1197035

Documents 1197220

1197476

Corrective Action 1196113

Documents 1196907

Resulting from 1196945

Inspection 1196946

1196947

1196951

1196959

1197174

1197175

1197359

200225

200227

Drawings FSK-12179-P21 Millstone Unit 3 Location of Leak Chase Panels and Ports 10/08/1976

Miscellaneous MP-24-CII-PRG Millstone Station Containment Inservice Inspection Program Revision

Schedule/Detailed Plan 004-06

MP-24-CII-PRG Millstone Station Containment Inservice Inspection Program Revision 007

Schedule/Detailed Plan

U3-24-ISI-PRG- Millstone Station Unit 3 Fourth Ten-Year Interval Inservice Revision 1

Interval 4 Inspection Plan

71111.11Q Miscellaneous MP2 LORP Evaluated Simulator Exam EXAM#: ES22301 Revision 0

Procedures AD-AA-102 Procedure Use and Adherence Revision 16

OP-AA-100 Conduct of Operations Revision 44

PI-AA-5000 Human Performance Revision 11

SP 2612B 'C' Service Water Pump Tests Revision 021

SP 2625E HPSI Header Stop Valve Tests Revision 001

71111.12 Corrective Action CA11056330

Documents CR1194399

CR1195831

71111.13 Procedures OP 3211 Solid Plant Pressure Control (ICCE) Revision 1

OP-MP-610 Protected Equipment Revision 38

WM-AA-301 Attachment 3 High Risk Plan Actions 05/26/2022

71111.15 Corrective Action CR1086618

Documents CR1196298

CR1196722

CR1196758

CR1197899

CR1198485

Drawings 25203-26018 Diesel Generators Starting Air Revision 15

Miscellaneous Lab No. Lube Oil Analysis Management System Sample Analysis Sample Date

2204070819 Report for M3 3EGS*EGB Engine Sump 03/22/2022

71111.15 Procedures MP 3710AA- Lubrication Maintenance Technique Reactor CCP Pump Revision 5

118M Motor Oil Change

OP 3345A-015 EDG B Operating Log Log for

01/25/2022

OP 3346A-015 EDG B - Operating Log Log for

08/13/2021

to

08/14/2021

OP 3346A-015 EDG B Operating Log Log for

11/05/2017

OP 3346A-015 EDG B Operating Log Log for

03/22/2022

OP 3346A-015 EDG B Operating Log Log for

2/23/2022

SP 600.7-006 Electric Fire Pump M7-8 Annual Operability Demonstration Revision 6

Work Orders 53103096287

53103138022

203341686

203344436

20394049

71111.18 Procedures MP-DC-000-MP3- Replacement of Instrument Transmitters for Auxiliary Revision 1

2-01030 Feedwater Flow & Steam Generator Level

MP3-20-01070 B Emergency Diesel Generator Voltage Regulator Revision 4

Replacement

71111.19 Calculations 25203-ER-11- MP2 East and West Switchgear Rooms Loss of Ventilation Revision 0

0001 Study for PRA Purposes

Corrective Action CR1200918

Documents CR1201496

CR1202554

Miscellaneous Calculation Number: NM-027-ALL MP3 Active Valve Revision 4

Response Times

Millstone Unit 3 Design Bases Summary for the Main Steam Revision 0

System

71111.19 Procedures MP 2720V Pressurizer Proportional Heater Controller Revision 006

MP-PROC-OPS- Starting Air Pressure Low C-7 Revision

ARP 2591A-033 001-04

OP-M2-MOP- West 125 Volt DC Vital Switchgear Room Cooling Revision 2

VEN-006

PA-RMSC-1391 Loss of Room Cooling in PRA Modeling April 2020

SP 2602E-001 Pressurizer Heater Capacity Test Revision 003

SP 2613A-001 Periodic DG Operability Test, Facility 1 (Fast Start, Loaded Revision 23

Run)

SP 2624B B Emergency Diesel Generator Auxiliaries Inservice Revision 002

Testing

SP 3616A.1 Main Steam System Valve Operability Tests Revision 021

SPROC ENG21- MP3 "B" Emergency Diesel Generator Basler Electric SER- Revision 0

3-014 CB Excitation System Verification of Installation and

Connections

Work Orders 53203301387

71111.20 Procedures EN 31007 Refueling Operations Revision 11

OP 3202 Reactor Startup (ICCE) Revision 26

OP 3207 Reactor Shutdown Revision 20

OP 3208 Plant Cooldown Revision 36

OP 3209B Shutdown Margin Revision 11

OP 3210B Refueling Operations Revision 13

OP 3216 Reactor Coolant System Drain (ICCE) Revision 19

OU-AA-200 Shutdown risk Management Revision 13

OU-M3-201 Shutdown Safety Assessment Checklist Revision 30

71111.22 Procedures C OP 200.16 Beyond Design Basis Operator Aids Revision 3

MA-MP-BDB-101 BDB Preventive Maintenance Revision 8

MP-PROC-MP- Containment Gaseous and Particulate Process Radiation Revision 8

SP 2404AK34 Monitor RM 8262 Functional Test

MP-VTM-000- Skid Trailer Manual for BDB Auxiliary Feed Pump Revision 000

205-008-009

SP 2403M Refueling Water Storage Tank Level Functional Test Revision 003

SP 2404AK34 Containment Gaseous and Particulate Process Radiation Revision 8

Monitor RM 8262 Functional Test

SP 2612A 'A' Service Water Pump Tests Revision 023

Work Orders 53203322683

203335609

71152A Corrective Action CA11063974

Documents CA11063975

CA11083750

CA3061625

CA9206739

CR1188862

CA99206739

Miscellaneous AD-AA-100 Technical Procedure Approval Form - Revisions to SP 01/14/2022

2654D (Rev. 009), SP 2654D-001 (Rev. 008) &

SP 2654D-002 (Rev. 003)

Procedures MP-GARDMP- Causal Evaluation Methods Revision 7

000-PI-AA-300-

3004

MP-GARDMP- Human Performance (HU) Revision 11

000-PI-AA-5000

MP-PROC-000- Verification Practices Revision 4

PI-AA-500

MP-PROC-OPS- 'A' Emergency Diesel Generator Revision 38

OP 2346A

MP-PROC-OPS- Emergency DG Pre-Lube and Air Roll Revision 8

SP 2654D

MP-PROC-OPS- Emergency DG Pre-Lube and Air Roll Revision 9

SP 2654D

MP-PROC-OPS- Emergency DG Pre-Lube and Air Roll Revision 10

SP 2654D

MP-PROC-OPS- "A" Emergency DG Pre-Lube and Air Roll Revision 7

SP 2654D-001

Work Orders 53203220616

203248423

71153 Corrective Action CA10834266

Documents CA9206748

CR1188959

CR1189837

71153 Miscellaneous MP3 PM Change Request 99-1625 Evaluation

Procedures ER-AA-PRS-1010 Preventive Maintenance Task Basis and Maintenance Revision 15

Strategy

30