IR 05000263/2020001

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Integrated Inspection Report 05000263/2020001
ML20125A337
Person / Time
Site: Monticello Xcel Energy icon.png
Issue date: 05/04/2020
From: Hironori Peterson
Region 3 Branch 3
To: Conboy T
Northern States Power Co
References
IR 2020001
Download: ML20125A337 (15)


Text

May 4, 2020

SUBJECT:

MONTICELLO NUCLEAR GENERATING PLANT - INTEGRATED INSPECTION REPORT 05000263/2020001

Dear Mr. Conboy:

On March 31, 2020, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Monticello Nuclear Generating Plant. On April 7, 2020, the NRC inspectors discussed the results of this inspection with you and other members of your staff. The results of this inspection are documented in the enclosed report.

No findings or violations of more than minor significance were identified during this inspection.

This letter, its enclosure, and your response (if any) will be made available for public inspection and copying at http://www.nrc.gov/reading-rm/adams.html and at the NRC Public Document Room in accordance with Title 10 of the Code of Federal Regulations 2.390, Public Inspections, Exemptions, Requests for Withholding.

Sincerely,

/RA/

Hironori Peterson, Chief Branch 3 Division of Reactor Projects

Docket No. 05000263 License No. DPR-22

Enclosure:

As stated

Inspection Report

Docket Number:

05000263

License Number:

DPR-22

Report Number:

05000263/2020001

Enterprise Identifier: I-2020-001-0049

Licensee:

Northern States Power company, Minnesota

Facility:

Monticello Nuclear Generating Plant

Location:

Monticello, MN

Inspection Dates:

January 01, 2020 to March 31, 2020

Inspectors:

D. Krause, Resident Inspector

J. Nance, Reactor Engineer

J. Robbins, Acting Sr. Resident Inspector

A. Shaikh, Senior Reactor Inspector

D. Szwarc, Senior Reactor Inspector

P. Zurawski, Senior Resident Inspector

Approved By:

Hironori Peterson, Chief

Branch 3

Division of Reactor Projects

SUMMARY

The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Monticello Nuclear Generating Plant, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.

List of Findings and Violations

No findings or violations of more than minor significance were identified.

Additional Tracking Items

None.

PLANT STATUS

Monticello began the inspection period operating at approximately 100 percent power and, with the following exceptions, remained at that level throughout the inspection period. Monticello performed multiple flexible power operations over the quarter, for electric grid efficiencies in the early mornings, reducing power to approximately 80 percent then returning to 100 percent power. On March 13, 2020, the unit was down-powered to 75 percent for control rod sequence exchange and quarterly turbine valve testing. Upon completion, the unit was returned to 100 percent power.

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/readingrm/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. From January 1 - March 19, 2020, the inspectors performed plant status activities described in IMC 2515, Appendix D, Plant Status, and conducted routine reviews using IP 71152, Problem Identification and Resolution. 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 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 and during that time conducted plant status activities as described in IMC 2515, Appendix D; and observed risk significant activities when warranted. 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 the cases where it was determined the objectives and requirements could not be performed remotely, management elected to postpone and reschedule the inspection to a later date.

REACTOR SAFETY

71111.01 - Adverse Weather Protection

Impending Severe Weather Sample (IP Section 03.02) (1 Sample)

(1) The inspectors evaluated the adequacy of the overall preparations to protect risk-significant systems from impending extreme low temperatures and large snow expected on January 16, 2020

71111.04 - Equipment Alignment

Partial Walkdown Sample (IP Section 03.01) (3 Samples)

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

(1) Emergency Diesel Generator (EDG) 11 fuel oil system post maintenance on January 21, 2020
(2) MCC-111 - Lower 4 KV switchgear - protected for RPS MGs on January 30, 2020
(3) Upper 4 KV Switchgear - building scaffold close to sensitive equipment on March 19, 2020

Complete Walkdown Sample (IP Section 03.02) (1 Sample)

(1) High Pressure Core Injection system full system alignment during Reactor Core Isolation Cooling planned maintenance outage on February 11 - 12, 2020

71111.05 - Fire Protection

Fire Area Walkdown and Inspection Sample (IP Section 03.01) (5 Samples)

The inspectors evaluated the implementation of the fire protection program by conducting a walkdown and performing a review to verify program compliance, equipment functionality, material condition, and operational readiness of the following fire areas:

(1) FZ-08, Cable Spreading Room on March 9, 2020
(2) FZ-02-C, West HCU on March 18, 2020
(3) FZ-03-A, Recirc MGs on March 17, 2020
(4) FZ-07-A, 125V Division 1 Battery on March 19, 2020
(5) FZ-13-A, Lube Oil Storage Tank on March 19, 2020

Fire Brigade Drill Performance Sample (IP Section 03.02) (1 Sample)

(1) Fire Drill on February 22, 2020

71111.06 - Flood Protection Measures

Inspection Activities - Internal Flooding (IP Section 03.01) (1 Sample)

The inspectors evaluated internal flooding mitigation protections in the:

(1) Lower Emergency Filtration Train (EFT) Building 933 ft level on March 5, 2020

71111.11Q - Licensed Operator Requalification Program and Licensed Operator Performance

Licensed Operator Performance in the Actual Plant/Main Control Room (IP Section 03.01) (1 Sample)

(1) The inspectors observed and evaluated licensed operator performance in the Control Room during scheduled flex power operations when the licensee discovered the Gardell Software used to determine thermal power limits was not functioning due to the 2020 Leap Year Programming Issue on March 1, 2020

Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)

(1) The inspectors observed and evaluated Resident Inspector Quarterly Review of Licensed Operator Requalification on March 9, 2020

71111.12 - Maintenance Effectiveness

Maintenance Effectiveness (IP Section 03.01) (2 Samples)

The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components (SSCs) remain capable of performing their intended function:

(1)15 - 24vDC Battery and Battery Charger on February 4, 2020 through February 7, 2020 (2)16 Instrument Air Compressor rework on January 30, 2020

71111.13 - Maintenance Risk Assessments and Emergent Work Control

Risk Assessment and Management Sample (IP Section 03.01) (5 Samples)

The inspectors evaluated the accuracy and completeness of risk assessments for the following planned and emergent work activities to ensure configuration changes and appropriate work controls were addressed;

(1)16 Instrument Air Compressor on January 30, 2020

(2) V-AH-4A dampers failed to open on January 29, 2020
(3) MO-2009, Residual Heat Removal (RHR) Torus Cooling Injection/Test Inboard Isolation Valve Testing Anomaly and Degraded Parts on February 19, 2020
(4) Floating and non-floating foreign material found in the standby liquid control test tank from February 5, 2020 - February 21, 2020
(5) DPIS-2-129C, Low Pressure Coolant Injection (LPCI) Loop Select Bellows failure on February 13, 2020

71111.15 - Operability Determinations and Functionality Assessments

Operability Determination or Functionality Assessment (IP Section 03.01) (5 Samples)

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

(1) High Pressure Core Injection system operability evaluation (2)24 vdc Battery #15 functionality / operability evaluation
(3) Valve Stem position test indicator AOV-008 failed calibration - impacts to PCIVs
(4) XP-1, Standby Liquid Control Poison Tank Outlet Valve bonnet gasket found to be non-safety related material
(5) MOV Fatigue Life Cycling

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) Residual Heat Removal Seal Cooler Engineering Change Request to replace leaking fittings on RHR water side of seal cooler

71111.19 - Post-Maintenance Testing

Post-Maintenance Test Sample (IP Section 03.01) (6 Samples)

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

(1)4056-01, CRV-EFT, V-EAC-14A Condenser Inspection and Cleaning PMT, WO 700040037, CAP 501000036284, on January 8, 2019

(2) MO-2373 Main Steam Line Drain Inboard Isolation valve 480V Breaker, B4333, PMT, WO 700039522, CAP 501000036831, on January 22, 2020
(3) LS-23-90, HPCI Steam Supply drain Valve level switch PMT, WO 700069545, CAP 501000036758, on January 29, 2020 (4)12 Core Spray Pump, P-208B PMT on February 18, 2020
(5) MO-2009, RHR-Torus Cooling Injection/Test Inboard Isolation Valve PMT on February 19, 2020
(6) XP-17, Standby Liquid Control Test Tank Suction Isolation Valve PMT on February 21, 2020

71111.22 - Surveillance Testing

The inspectors evaluated the following surveillance tests:

Surveillance Tests (other) (IP Section 03.01)

(1) Emergency Diesel Generator (EDG) 12 Quarterly Surveillance Test on January 27, 2020

Inservice Testing (IP Section 03.01) (3 Samples)

(1) Control Rod Drive Hydraulic System Quarterly Valve Exercise Test, WO 700060442, on January 7, 2019 (2)0255-11-III-3, 13 ESW Pump Flow Test, WO 700060427, on January 8, 2019
(3) OPS-SLC, 0255-02-III, SBLC Pump In Service on February 3, 2020

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

(1)0143, Drywell - Torus Quarterly Vacuum Breaker Check, WO 700067138, on January 8, 2019

71114.06 - Drill Evaluation

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

The inspectors evaluated:

(1) RQ-SS-175 on March 9,

OTHER ACTIVITIES - BASELINE

===71151 - Performance Indicator Verification

The inspectors verified licensee performance indicators submittals listed below:

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

(1) Unit 1 (January 2019 - December 2019)

IE03: Unplanned Power Changes per 7000 Critical Hours Sample (IP Section 02.02) (1 Sample)

(1) Unit 1 (January 2019 - December 2019)

IE04: Unplanned Scrams with Complications (USwC) Sample (IP Section 02.03) (1 Sample)

(1) Unit 1 (January 2019 - December 2019)

71152 - Problem Identification and Resolution

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

The inspectors reviewed the licensee's corrective action and adverse condition monitoring programs, from July 1 - December 31, 2019

(1) Potential adverse trends involving repetitive issues of the Control Room Ventilation 'B' train compressor

Annual Follow-up of Selected Issues (IP Section 02.03) (1 Sample)

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

(1) Heating Boiler Trips and Maintenance Issues

===71153 - Followup of Events and Notices of Enforcement Discretion

Event Followup (IP Section 03.01)===

The inspectors evaluated an off-site event for potential E-Plan Entry

(1) Becker Recycling Center Fire potentially involving hazardous materials and toxic gasses

INSPECTION RESULTS

Observation: Multiple heating boiler failures occurred during the 2019/20 winter season having the potential to impact reactor building differential pressure and steam chase temperatures.

71152 During the past two winters (2019 and 2020), the licensee has had many issues with their heating boiler. Although the heating boiler is not safety-related, failures of this system negatively affect the safety-related reactor building ventilation system. Specifically, reactor building ventilation is required to ensure that reactor building differential pressure remains negative and that temperatures in the steam chase area remain below limits that can require the reactor be shutdown. The inspectors reviewed the previous boiler failures and determined that they were not reportable, as the licensee did not approach any Technical Specification limits. The licensee issued a trend Corrective Action QIM, 501000034054, to document and acknowledge challenges with heating boiler reliability.

The inspectors reviewed licensee corrective actions associated with Corrective Action QIM 501000034054; Abnormal trend in heating boiler trips, QIM 501000033437; P-76A unusually noisy & HTB trip, QIM 501000033517; Heating boiler lockouts, and others.

The inspectors assessed the following performance attributes in their review:

  • Complete and accurate identification of the problem in a timely manner commensurate with its safety significance and ease of discovery;
  • Consideration of the extent of condition, generic implications, common cause, and previous occurrences;
  • Evaluation and disposition of operability/functionality/reportability issues;
  • Classification and prioritization of the resolution of the problem commensurate with safety significance;
  • Identification of corrective actions, which were appropriately focused to correct the problem; and
  • Completion of corrective actions in a timely manner commensurate with the safety significance of the issue.

The inspectors selected this sample due to the operability impact on reactor building ventilation and steam chase temperature, both safety significant systems. Inspectors focused review of the above attributes on the licensees corrective actions associated with QIMs 501000034054, 501000033517 and 501000033437. Inspectors did not identify a performance deficiency with this issue.

Observation: Potential adverse trends involving repetitive issues associated with the Control Room Ventilation 'B' train compressor.

71152 The inspectors performed a semi-annual review, of the licensee's corrective action and adverse condition monitoring programs, from July 1 - December 31, 2019, for potential adverse trends. The inspectors noted several failures of the Control Room Ventilation 'B' train compressor to start. Based on these events, the inspectors reviewed the licensees corrective action program (CAPs 501000029837, V-EAC-14B Compressor Trip on Startup and 501000032534, V-EAC-14B Compressor Tripped During Swap), trend reports, major equipment problem lists, system health reports, self-assessments, and additional documents, to identify trends that might indicate the existence of a more significant safety issue.

Programmatic requirements and processes were also reviewed to determine whether adverse conditions related to control room ventilation were being appropriately tracked, managed, and resolved. The inspectors also reviewed the licensees selection of criteria or set points for which further evaluation or action was designated to assess the health of the adverse condition monitoring program.

The inspectors did not identify any significant trends that might indicate the existence of a more significant safety concerns that had not been previously addressed by the licensee, nor did the inspectors identify any performance deficiency with this issue.

Observation: Becker Recycling Center Fire potentially involving hazardous materials and toxic gasses.

71153 The inspectors evaluated Site impacts, and licensees response to the Becker Recycling Center Fire. This issue was selected due to the potential for meeting E-Plan entry conditions during an off-site event. i.e., a fire potentially involving hazardous materials and toxic gasses that might impede free moment of plant personnel on-site or responding to the protected area during the fire (February 18 - 21, 2020). No alarms occurred nor were any site action levels reached during the event. The fire was brought under control within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />, by off-site responders, prior to meeting criteria for event reporting. The licensee has documented lessons learned during this event in CAP 50100037884, Becker Recycling Facility Fire.

The inspectors did not identify any programmatic or process inadequacies, nor did the inspectors identify any performance deficiency with this issue.

EXIT MEETINGS AND DEBRIEFS

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

  • On April 7, 2020, the inspectors presented the integrated inspection results to Mr. T. Conboy, Site Vice President, and other members of the licensee staff.

DOCUMENTS REVIEWED

Inspection

Procedure

Type

Designation

Description or Title

Revision or

Date

71111.01

Corrective Action

Documents

501000036610

Bromide Vent Plugged with Ice

Procedures

B.08.07-05

Operations Manual - Heating and Ventilating

1444

Pre and Post Severe Weather Inspection Checklist

C.4-B.08.03.A

Operations Manual Abnormal Procedures Loss of Heating

Boiler

C.4-B.08.07.A

Operations Manual Abnormal Procedures Ventilation

System Failure

71111.04

Corrective Action

Documents

501000037877

HPCI-90, Valve not Included in 2154-10

Procedures

2154-10

High Pressure Coolant Injection System Prestart Valve

Checklist

B.09.6-05

Ops Manual 4.16 kV Station Auxiliary System Operation

NF-36298-1

Electrical Load Flow One-Line Diagram

117

NH-36051

P&ID Diesel Oil System

NH-36051-1

P&ID Diesel Oil System

71111.05

Corrective Action

Documents

501000038446

Replaced CSR Thermal Detector Issue

Fire Plans

28

Cable Spreading Room Halon System

Fire Zone -

Strategy A.3-03-A

Recirc MG Set Room

Fire Zone -

Strategy A.3-07-A

Division 1 125 VDC BAttery Room

Fire Zone -

Strategy A.3-08

Cable Spreading Room

Fire Zone -

Strategy A.3-13-A

Lube Oil Tank Room

Fire Zone-

Strategy A.3-02-C

Reactor Building (West HCU Area) - Elevation 936'

Miscellaneous

A.3-20

Fire Brigade Drill Guide, Heater Boiler Fuel Pump Fire, Drill

Guide "20.01"

71111.05

Miscellaneous

STRATEGY

A.3-20

Fire Zone 20 Auxiliary Boiler Room

71111.06

Miscellaneous

DBD-T.08

Internal Flooding

Procedures

AWI-08.01.03

HELB Practices

C.4-1 Abnormal

Procedures

Plant Flooding

Strategy A.3-31-B

Fire Zone 31-B, EFT Building First Floor (Div II)

71111.11Q Corrective Action

Documents

501000038262

Backup Thermal Limit Monitoring

501000038280

Gardel not Updating

Miscellaneous

Ops Man C.2-01

Power Operation - Function and General Description

RQ-SS-175

LOR/DEP Simulator Scenario

Procedures

DP-NF-NAD-19

Monticello Gardel Backup Using SIMULATE-3

NUC-03.12

Periodic Core Follow Data For NAD

71111.12

Corrective Action

Documents

501000035940

Battery Cells 16 - 18 SG Found Low

2/19/2019

501000037160

Late Identification of Parts for K-1F

501000037180

Air Compressor Loading/Unloading Issues

Work Orders

WO 700058662

4953-PM, Instrument and Service Air System -

Air Compressors

01/30/2020

WO 700058665

K-1F - Replace Drive Coupling Insert PM

01/27/2020

WO 700061191

FINE-D5, Replace Cells 16, 17, & 18 in 15 Battery

2/17/2019

WO 700063469

No. 15 24 VDC Battery Operability Check

2/19/2019

71111.13

Corrective Action

Documents

501000036631

V-AH-4A Isolation Damper Failed to Open

501000037180

Air Compressor Loading/Unloading Issues

501000037301

Leak/FME into T-201 SLC Test Tank

501000037384

Flakes of Material in SBLC Test Tank

501000037674

Substance Observed From DPIS-2-129C

501000037819

MO-2009 As Found Anomaly

501000037836

MO-2009 Disconnected Motor Lead

501000037854

Degraded Parts Found on MO-2009

Work Orders

7000070493

Recirc Loops DP-LPCI Select Interlock Replace Switch

2/13/2020

700058662

4953-PM, Instrument and Service Air Compressors

01/30/2020

700063062

MO-2009 RHR-Torus Cooling Injection/Test Inboard

Isolation Valve Testing

2/19/2020

700069350

Surveillance for Secondary Containment Isolation Damper

V-D-61

01/29/2020

71111.15

Corrective Action

Documents

501000035940

Battery Cells 16-18 SG Found Low, Drawing

NE-36640-6, 24V DC Distribution - Panel D15, D25

501000036758,

Received C03-B-10 Annunciator, 01/21/2020 and eSOMS

Plant Narrative Log

01/21/2020

501000037190

AOV-008 (30 Inch Stem Position Encoder) Failed Vendor

Calibration

501000037919

MOV Fatigue Life Cycling

501000038319

XP-1 has NSR Gasket

Drawings

NE-36640-6

24V DC Distribution - Panel D15, D25

Engineering

Changes

EC 0000026038

EQ MOV Cycling Limit Extension to 4000 Cycles for

Limitorque and Rotork NA1 Actuators

Miscellaneous

EQ 98-026

Limitorque Motor Operators (50.49)

71111.18

Corrective Action

Documents

501000038353

RHR Seal Cooler Issue

Miscellaneous

ERC

601000002015

RHR Seal Cooler Connection

Work Orders

700062848

P-202A, Repair Seal Cooler Leak

71111.19

Corrective Action

Documents

501000036284

TCV-4030A Leaking

501000036298

V-EAC-14A Condenser Drain Plug Degraded

501000036758

Received C03-B-10 Annunciator

501000036831

B4333 PM did not Complete as Scheduled

700039522

MO-2373 Main Steam Line Drain Inboard Isolation Valve

480V Breaker, B4333, Perform PMT

01/22/2020

700040037

CRV-EFT V-EAC14A Condenser Inspection and Cleaning

PMT

01/08/2020

700040125

4058-02-OCD, 12 Core Spray Pump, P-208B Pressure Test

PMT

2/18/2020

700063062

MO-2009, RHR-Torus Cooling Injection/Test Inboard

Isolation Valve PMT

2/19/2020

700069545

HPCI Steam Drain Hi Level Bypass LS-23-90 PMT

01/29/2020

700070302,

XP-17 Replace Bonnet Gasket

2/21/2020

71111.22

Corrective Action

Documents

501000037405

XP-16 Possible Leak By

Work Orders

700060427

255-11-III-3, 13 ESW Pump Flow Test

01/08/2020

700060442

CRH 0255-01-IA - Control Rod Drive Hydraulic System

Quarterly Valve Exercise Test

01/07/2020

700060767

0187-02, 12 Emergency Diesel Generator Quarterly

Surveillance Test

700063330

OPS-SLC, 0255-02-III, SBLC Pump In Service

2/19/2020

700067138

0143, Drywell - Torus Quarterly Vacuum Breaker Check

01/08/2020

71114.06

Miscellaneous

RQ-SS-175

LOR/DEP Simulator Scenario

71151

Miscellaneous

Unplanned Scrams per 7000 Critical Hours, QF0445,

Monthly Submission Forms (January - December 2019)

Unplanned Power Changes per 7000 Critical Hours,

QF0445, Monthly Submission Forms (January - December

2019)

Unplanned Scrams/Complications, QF0445, Monthly

Submission Forms (January - December 2019)

71152

Corrective Action

Documents

501000029837

V-EAC-14B Compressor Trip on Startup

501000023730

Heating Boiler Lockout

501000030237

CRDs Refurbished Without AMSE XI RR Plan

501000031053

ESW-1-2 IST Test not Performed in 1R29

501000031071

Trend in Outage Activity Closure

501000032534

V-EAC-14B Compressor Tripped During Swap

501000033437

P-76A Unusually Noisy & HTB Trip

501000033517

Heating Boiler Lockouts

501000034054

Abnormal Trend In Heating Boiler Trips

501000036107

Heating Boiler Trip

501000036132

Loss of Heating Boiler Enhancements

Procedures

B.08.07-05

Operations Manual System Operation, Heating and

Ventilating

C.B.08.03.A

Operations Manual Abnormal Procedure, Loss of Heating

Boiler

71153

Corrective Action

Documents

501000037884

Becker Recycling Facility Fire

Procedures

5790-101-02

Emergency Action Level Matrix

13