IR 05000263/2020001
ML20125A337 | |
Person / Time | |
---|---|
Site: | Monticello ![]() |
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:
Report Number:
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
- (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
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
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
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"
Miscellaneous
STRATEGY
A.3-20
Fire Zone 20 Auxiliary Boiler Room
Miscellaneous
DBD-T.08
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
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
4953-PM, Instrument and Service Air System -
Air Compressors
01/30/2020
K-1F - Replace Drive Coupling Insert PM
01/27/2020
FINE-D5, Replace Cells 16, 17, & 18 in 15 Battery
2/17/2019
No. 15 24 VDC Battery Operability Check
2/19/2019
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
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
Drawings
NE-36640-6
24V DC Distribution - Panel D15, D25
Engineering
Changes
EQ MOV Cycling Limit Extension to 4000 Cycles for
Limitorque and Rotork NA1 Actuators
Miscellaneous
EQ 98-026
Limitorque Motor Operators (50.49)
Corrective Action
Documents
501000038353
RHR Seal Cooler Issue
Miscellaneous
601000002015
RHR Seal Cooler Connection
Work Orders
700062848
P-202A, Repair Seal Cooler Leak
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
01/08/2020
700040125
4058-02-OCD, 12 Core Spray Pump, P-208B Pressure Test
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,
2/21/2020
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
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)
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
Corrective Action
Documents
501000037884
Becker Recycling Facility Fire
Procedures
5790-101-02
Emergency Action Level Matrix
13