IR 05000263/2025002
| ML25218A046 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 08/06/2025 |
| From: | Dariusz Szwarc NRC/RGN-III/DORS/RPB3 |
| To: | Hafen S Northern States Power Company, Minnesota |
| References | |
| IR 2025002 | |
| Download: ML25218A046 (1) | |
Text
SUBJECT:
MONTICELLO NUCLEAR GENERATING PLANT - INTEGRATED INSPECTION REPORT 05000263/2025002
Dear Shawn Hafen:
On June 30, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Monticello Nuclear Generating Plant. On July 16, 2025, 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, Dariusz Szwarc, Chief Reactor Projects Branch 3 Division of Operating Reactor Safety Docket No. 05000263 License No. DPR-22
Enclosure:
As stated
Inspection Report
Docket Number:
05000263
License Number:
Report Number:
Enterprise Identifier:
I-2025-002-0058
Licensee:
Northern States Power Company, Minnesota
Facility:
Monticello Nuclear Generating Plant
Location:
Monticello, MN
Inspection Dates:
April 01, 2025, to June 30, 2025
Inspectors:
Z. Fleming, Project Engineer
T. Hartman, Senior Resident Inspector
C. Norton, Senior Resident Inspector
S. Orth, Senior Health Physicist
E. Rosario, Trans & Storage Safety Inspector
Approved By:
Dariusz Szwarc, Chief
Reactor Projects Branch 3
Division of Operating Reactor Safety
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
The unit began the inspection period at full achievable power as they were coasting down toward the refueling outage. The following power changes were performed during the inspection period:
- On April 2, 2025, the licensee reduced power to approximately 83 percent power for a routine rod pattern adjustment. Power was subsequently restored to full achievable power the same day.
- On April 3, 2025, the licensee reduced power to approximately 85 percent to clean the main condenser tubes. On April 4, 2025, the licensee increased power to full achievable power.
- On April 9, 2025, the licensee reduced power to approximately 76 percent for a routine rod pattern adjustment. Power was subsequently restored to full achievable power the same day.
- On April 18, 2025, the licensee shutdown the unit and began refueling outage 32.
- Following completion of the refueling outage, the reactor was restarted and taken to critical on May 24, 2025. The unit reached full power operation on May 27, 2025.
- On June 1, 2025, the licensee commenced a shutdown to replace the C safety relief valve. The licensee restarted the reactor and reached approximately 30 percent power on June 4, 2025. The licensee held power steady at around 30 percent until June 9, 2025, when they increased power to 100 percent.
The unit remained at or near 100 percent 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, observed risk significant activities, and completed onsite 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.
REACTOR SAFETY
71111.01 - Adverse Weather Protection
Seasonal Extreme Weather Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated readiness for seasonal extreme weather conditions prior to the onset of summer temperatures for emergency diesel generators (EDGs) and safety-related bus 15
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 severe weather including lightning and tornado watch on May 15, 2025
71111.04 - Equipment Alignment
Partial Walkdown Sample (IP Section 03.01) (4 Samples)
The inspectors evaluated system configurations during partial walkdowns of the following systems/trains:
- (1) Division 2 control room ventilation/emergency filtration train (CRV/EFT) system on April 8, 2025
- (2) Division 1 EDG starting air system on May 15, 2025
- (3) Reactor core isolation cooling (RCIC) system on May 20, 2025
- (4) Control rod drive hydraulic control units, banks 1 and 4 on May 21, 2025
Complete Walkdown Sample (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated system configurations during a complete walkdown of the standby liquid control system on May 20, 2025
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) Fire Zone (FZ) 17, turbine building north cable corridor 941' on April 2, 2025
- (2) FZ 16, corridor, turbine building east & west (elevations 911' and 931'),
on April 3, 2025
- (3) FZ 9, control room on April 4, 2025
- (4) FZ 2B, east hydraulic control unit (HCU) area on April 7, 2025
- (5) FZ 19C, feedwater pipe chase on April 9, 2025
Fire Brigade Drill Performance Sample (IP Section 03.02) (1 Sample)
- (1) The inspectors evaluated the onsite fire brigade training and performance during an announced fire drill on April 6, 2025
71111.06 - Flood Protection Measures
Flooding Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated internal flooding mitigation protections outside the lower 4kV room
71111.07A - Heat Exchanger/Sink Performance
Annual Review (IP Section 03.01) (1 Sample)
The inspectors evaluated readiness and performance of:
- (1) Main condenser during dredging of service water intake bay on April 07, 2025
71111.08G - Inservice Inspection Activities (BWR)
BWR Inservice Inspection Activities Sample - Nondestructive Examination and Welding
Activities (IP Section 03.01)
The inspectors evaluated boiling-water reactor nondestructive testing, flaw evaluation, and welding activities by reviewing the following examinations from April 21, 2025, to May 22, 2025:
(1)
1. Visual examinations of reactor recirculation (RR) seismic support and restraint
for component identifications (IDs): H6, H10, and H11
2. Visual examinations of main steam (MS) valve internal surfaces and bolts
for component IDs: V4 and B8
3. Visual examinations of the reactor vessel internals associated with the
InVessel Visual Inspections (IVVI)
4. Relevant indication to BWRVIP18 Rev. 2A accepted for continued service
on pipe to junction box weld of core spray piping component ID: CSP-P3a
5. Ultrasonic examination of the RR pipe-topipe weld component IDs:
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 control rod pattern adjustment on April 2, 2025
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed and evaluated just in time training (JITT) for reactor startup and reactor vessel pressure test in the simulator on April 15, 2025
71111.12 - Maintenance Effectiveness
Maintenance Effectiveness (IP Section 03.01) (3 Samples)
The inspectors evaluated the effectiveness of maintenance to ensure the following structures, systems, and components (SSCs) remain capable of performing their intended function:
- (1) Drywell structure walkdown during refueling outage on April 24, 2025
- (2) Licensee actions after failure to schedule monthly division 2 diesel generator surveillance test outside the division 1 emergency bus maintenance window on April 29, 2025
- (3) Removal of load test cart for Y81 inverter replacement on May 05, 2025
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) Work Order 7001285290075, Replacing safety-related 200 Amp fuse with 150 Amp fuse on April 30, 2025
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) Secondary containment reactor building equipment hatch operation on April 03, 2025
- (2) Failure of Division 2 control room ventilation recirculation fan damper to modulate on April 08, 2025
- (3) Torus instrument air isolation valve exercise on April 08, 2025
- (4) Control rod drive (CRD) changeout on May 03, 2025
- (5) Planning and risk management of manually backseating high pressure core injection (HPCI) inboard isolation valve (MO2034) on May 20, 2025
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (3 Samples)
The inspectors evaluated the licensees justifications and actions associated with the following operability determinations and functionality assessments:
(1)
===501000096997, VD9175B not functioning properly (2)501000096788, Recirculation inboard sample valve failed diagnostic test (3)501000099278, Alternate N2 relief valve leaking
71111.18 - Plant Modifications
Temporary Modifications and/or Permanent Modifications (IP Section 03.01 and/or 03.02)
=
The inspectors evaluated the following temporary or permanent modifications:
- (1) For over 90 days, HPCI pressure gauge PI23117 not reading properly and is compensated by a temporary flow meter for the purpose of ensuring the line is full of water
- (2) Placement of a jumper to temporally allow opening the RR system out board sample valve while a Group 1 Isolation signal is inserted
Severe Accident Management Guidelines Update (IP Section 03.03) (1 Sample)
- (1) The inspectors verified the site Severe Accident Management Guidelines were updated in accordance with the BWR generic sever accident technical guidelines and validated in accordance with NEI 14-01, Emergency Response Procedures and Guidelines for Beyond Design Basis Events and Severe Accidents, Revision 1.
71111.20 - Refueling and Other Outage Activities
Refueling/Other Outage Sample (IP Section 03.01) (2 Samples)
- (1) The inspectors evaluated refueling outage activities for RFO32 from April 18, 2025, to May 23, 2025.
- (2) The inspectors evaluated forced outage FO3301 to replace the C safety relief valve from June 1, 2025, to June 3, 2025.
71111.24 - Testing and Maintenance of Equipment Important to Risk
The inspectors evaluated the following testing and maintenance activities to verify system operability and/or functionality:
Post-Maintenance Testing (PMT) (IP Section 03.01) (17 Samples)
- (1) Work Order (WO) 7001360850070, A reactor protection system (RPS)
MG set after installation of temporary power supply modification on April 1, 2025
- (2) WO 7001285290095, Load test after Y81 inverter replacement on May 04, 2025
- (3) WO 7000409790020, EDG 11 governor after replacement on May 4, 2025
- (4) WO 7001140080020, Emergency service water pump 11, following preventive maintenance on May 4, 2025
- (5) WO 7000725210050, Stack gas dilution fan inlet damper, following preventive maintenance on May 5, 2025
- (6) WO 70012072220040, RCIC steam line inboard isolation valve, MO2075, following preventive maintenance on May 5, 2025
- (7) WO 7000409790020, EDG 11 governor after second replacement on May 06, 2025
- (8) WO 7000770560140, EDG 11 voltage regulator after replacement on May 06, 2025
- (9) WO 7001418960030, Recirc sample line inboard isolation valve, MO2790, following preventive maintenance on May 08, 2025
- (10) WO 7001134250020 PMT of core spray pump 11 discharge check valve after maintenance on May 9, 2025
- (11) WOs 700090273005, 700135316100, and 700113996040 Stroke timing division 1 LPCI inboard injection valve for partial PMT following maintenance on May 9, 2025
- (12) Various WOs, Final PMTs of control rod drives following maintenance that included drive replacements and HCU hydraulic control unit maintenance on May 13, 2025.
- (13) WO 7001224820070, Control rod drive timing test after CRD replacements on May 13, 2025
- (14) WO 7001380240110, Inboard main steam isolation valve local leak rate testing on May 13, 2025
- (15) WO 7001208290040, HPCI outboard isolation local leak rate testing after maintenance on May 14, 2025
- (16) WO 7001207010020, Outboard main steam isolation valve (MSIV) 11 after maintenance on May 14, 2025
- (17) WO 7001207530030, Drywell personnel airlock interlock test after interlock restoration on May 23, 2025
Surveillance Testing (IP Section 03.01) (4 Samples)
(1)0003, Drywell high pressure scram and group 2, 3, & SCTMT isolation test and calibration on April 14, 2025 (2)
===013702-06, Primary containment double-gasketed seals local leak rate testing (LLRT) on April 28, 2025 (3)013727, Transversing incore probe (TIP) system isolation valves pressure and LLRT on April 28, 2025
(1)0214, Drywell-tosuppression chamber vacuum breaker cycle pressure and leakage test, on May 23, 2025
Containment Isolation Valve Testing (IP Section 03.01) (1 Sample)
- (1) Outboard main steam isolation valves A and B LLRT on April 19, 2025
Diverse and Flexible Coping Strategies (FLEX) Testing (IP Section 03.02) (1 Sample)
- (1) WO 7001205450035, Portable fire pump operation on April 29, 2025
71114.06 - Drill Evaluation
Required Emergency Preparedness Drill (1 Sample)
- (1) Hostile action based drill on June 17,
RADIATION SAFETY
71124.01 - Radiological Hazard Assessment and Exposure Controls
Radiological Hazard Assessment (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated how the licensee identifies the magnitude and extent of radiation levels, identifies the concentrations and quantities of radioactive materials, and 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) (2 Samples)
The inspectors observed/evaluated the following licensee processes for monitoring and controlling contamination and radioactive material:
- (1) Workers exiting the radiologically controlled area (RCA)
- (2) Workers exiting the drywell access point
Radiological Hazards Control and Work Coverage (IP Section 03.04) (4 Samples)
The inspectors evaluated the licensees control of radiological hazards for the following radiological work:
(1)
1R32 - Torus - diving - inspect/clean (RWP 255119) and associated as low
as reasonably achievable (ALARA) plan (2)
1R32 - Reactor water cleanup (RWCU) E201C heat exchanger (HX) repair
(RWP 255121) and associated ALARA plan (3)
1R32 - RWCU - Replace drain pipes & RC valve (RWP 255126) and associated ALARA plan (4)
1R32 - Drywell (DW) CRD changeout (RWP 255509) and associated ALARA plan
High Radiation Area and Very High Radiation Area Controls (IP Section 03.05) (3 Samples)
The inspectors evaluated licensee controls of the following high radiation areas and very high radiation areas:
- (1) Reactor building 935' TIP cubicle (Door 60)
- (2) Reactor building 935' drywell access area
- (3) Material stored within the spent fuel pool (control of suspension lines)
Radiation Worker Performance and Radiation Protection Technician Proficiency (IP Section 03.06) (1 Sample)
- (1) The inspectors evaluated radiation worker and radiation protection technician performance as it pertains to radiation protection requirements.
71124.03 - InPlant Airborne Radioactivity Control and Mitigation
Temporary Ventilation Systems (IP Section 03.02) (2 Samples)
The inspectors evaluated the configuration of the following temporary ventilation systems:
- (1) Reactor building 1027' reactor head stand
- (2) Reactor building 962' reactor water cleanup area
Use of Respiratory Protection Devices (IP Section 03.03) (1 Sample)
- (1) The inspectors evaluated the licensees use of respiratory protection devices.
OTHER ACTIVITIES - BASELINE
===71151 - Performance Indicator Verification The inspectors verified licensee performance indicators submittals listed below:
MS05: Safety System Functional Failures Sample (IP Section 02.04)===
- (1) April 01, 2024, through March 31, 2025 BI01: Reactor Coolant System (RCS) Specific Activity Sample (IP Section 02.10) (1 Sample)
- (1) May 01, 2024, through March 31, 2025
BI02: RCS Leak Rate Sample (IP Section 02.11) (1 Sample)
- (1) April 01, 2024, through March 31, 2025
OR01: Occupational Exposure Control Effectiveness Sample (IP Section 02.15) (1 Sample)
- (1) May 01, 2024, through March 31, 2025 PR01: Radiological Effluent Technical Specifications/Offsite Dose Calculation Manual Radiological Effluent Occurrences (RETS/ODCM) Radiological Effluent Occurrences Sample (IP Section 02.16) (1 Sample)
- (1) May 01, 2024, through March 31, 2025
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) Licensee failure to promptly identify portions of the reactor pressure vessel (RPV)exceeded the limiting cooldown rate specified in the Pressure Temperature Limits Report
- (2) The licensees inability to manually open rollup doors of FLEX buildings
INSPECTION RESULTS
Observation: Corrective Actions to Address Procedural Deficiencies in Monitoring Reactor Pressure Vessel Cooldown Rates 71152A On February 28, 2024, following a reactor scram accompanied by a trip of the recirculation pumps, the licensee did not promptly identify that the reactor vessel (RPV) bottom exceeded the limiting cooldown rate specified in the pressure temperature limits report. As a result, the licensee did not complete the required technical specification action to determine if the reactor coolant system was acceptable for continued operation prior to starting the reactor and progressing to Mode 1. A non-cited violation for this issue was documented in Inspection Report 2024002. The inspectors selected this sample to follow up on the licensees corrective actions in response to the issue.
The licensee subsequently determined that procedure 0118, Reactor Vessel Temperature Monitoring, utilized a computer program that monitored only RPV belt line temperature during cool down but did not account for the RPV temperature stratification that occurs without recirculation. Corrective actions included modifying procedure 0118 to monitor temperatures for the entire RPV and display the point with the highest cool down rate.
On April 19, 2025, the inspectors observed the licensee cool down the RPV for RFO 32 utilizing the revised 0118. The cool down rate for all points on the RPV was monitored and the point with the highest cooldown rate prominently displayed. The inspectors identified no issues of concern associated with the licensees corrective actions.
Observation: Corrective Actions to Address Inability to Manually Open FLEX Building Doors 71152A On November 17, 2021, the licensee identified that the rope used to manually open the rollup doors of the FLEX building was missing. During loss of offsite power or station blackout, the inability to quickly open the rollup doors manually could hinder the ability to use the FLEX equipment as designed. The inspectors selected this issue as a sample based on the importance of the FLEX equipment and the strategies that could potentially be impacted by the identified issue.
Corrective actions included replacing the rope used to manually open the doors, as well as modifying OSP-FIR1489, B.5.B/FLEX Equipment Inventory, to include verification of the ability to manually open the rollup doors.
On April 29, 2025, the inspectors observed an inventory of FLEX equipment and verified the presence of the rope and the use of the updated inventory sheet. The inspectors identified no issues of concern and assessed that the corrective actions were adequate.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On July 16, 2025, the inspectors presented the integrated inspection results to S. Hafen, Site Vice President, and other members of the licensee staff.
- On April 24, 2025, the inspectors presented the radiation protection inspection results to S. Hafen, Site Vice President, and other members of the licensee staff.
- On May 22, 2025, the inspectors presented the inservice inspection activities for Monticello M1R32 outage inspection results to S. Hafen, Site Vice President, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Miscellaneous
OWI01.01
Operations Group Organization and Responsibility
Assignments
2000034760
1444, Pre and Post Severe Weather Inspection Checklist
7001349890010
1150, Summer Checklist
Procedures
A.6
Act of Nature
Corrective Action
Documents
Resulting from
Inspection
501000099079
RCIC Barometric Cond Insulation Damage
05/20/2025
NH170037
Main Control Room CRV/EFT System
Drawings
NX92164
Monticello Nuclear Generating Plant Air Starting System
E
215407
Standby Liquid Control System Prestart Valve Checklist
215413
RCIC System Prestart Valve Checklist
Procedures
215437
Control Rod Drive System Prestart Valve and Hydraulic
Control Unit Checklist
STRATEGY
A.302-B
Fire Zone 2B, East HCU Area
STRATEGY
A.309
Fire Zone 9, Control Room
STRATEGY
A.316
Fire Zone 16, Corridor, Turbine Building East & West
(Elevations 911' and 931')
STRATEGY
A.317
Fire Zone 17, Turbine Building North Cable Corridor 941'
STRATEGY
A.319-C
Fire Zone 19C, F.W. Pipe Chase
Fire Plans
STRATEGY
A.343
Fire Zone 43, Compressed Air Building
Miscellaneous
A.343
Fire Brigade Drill Guide, 17 Compressor B Cooling Pump
Motor Fire, Drill Guide 43.01
04/06/2025
Procedures
Ops Man
B.09.0605
G.15. Operation of the HELB Flood Barrier Lower 4kV
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Engineering
Changes
EC
6030000001641
DBD-S.04 Intake Structure
25PM
East Service Water Bay Inspection/Dredging
Procedures
26PM
West Service Water Bay Inspection/Dredging
501000097684
Light Particulate Inside Reactor Vessel
04/23/2025
501000097737
Bent Lift Tab on Jet Pump 15 WD1
04/25/2025
501000097771
Welded Attachment Drawing Discrepancy
04/25/2025
501000097842
RFO32 IVVI Indication: Core Spray P3a
04/25/2025
Corrective Action
Documents
501000097996
RFO32 IVVI Indication: TGGB
04/29/2025
Drawings
PEI01.02.04
Recirculation Loop A ISI Isometric Drawings (Figure 5.2)
MN25UT-003
Ultrasonic Examination of RR Pipe-toPipe Component ID:
W23 LS U
04/24/2025
MN25UT-004
Ultrasonic Examination of RR Pipe-toPipe Component ID:
W30 LS U
04/24/2025
MN25VT-013
Visual Examination (VT3) of RR Clevis, Lugs, and
Constant-Support Component ID: H6
04/25/2025
MN25VT-014
Visual Examination (VT3) of RR Sway Brace Component
ID: H11
04/25/2025
MN25VT-015
Visual Examination (VT3) of RR Double Spring and Lugs
Support Component ID: H10
04/25/2025
MN25VT-016
Visual Examination (VT1) of MS Valve Bolts Component ID:
B8
04/26/2025
MN25VT-017
Visual Examination (VT3) of MS Valve Internal Surfaces
Component ID: V4
04/26/2025
NDE Reports
MN25VT-028
Visual Examination (VT1) of New MS Valve Bolts
Component ID: B8
05/01/2025
FPPE-NDE402
Ultrasonic Examination of Austenitic Pipe Welds
PDI-UT2
Generic Procedure for the Ultrasonic Examination of
Austenitic Pipe Welds
J
Procedures
PEI02.05.05
Vessel Examination of Monticello Reactor Vessel Interior
Miscellaneous
SEG MTLOR-
JIT20250025
Startup JITT
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
SEG MTLOR-
JIT20250115
Reactor Vessel Pressure Test
2300
Reactivity Adjustment
28A
Procedures
C.205
Power Operation
84C
Engineering
Evaluations
MT2025EDG06
Stride to Extend the Emergency Diesel Generator (EDG)
Monthly Test Frequency
04/30/2025
3487
Drywell Entry Checklist
Procedures
FPOP-SFCP01
Surveillance Frequency Control Program
Radiation Work
Permits (RWPs)
255500
1R32 - DW GENERAL ACTIVITIES
04/24/2025
7001285290075
Replace 200A Fuse With 150A Fuse
04/30/2025
Work Orders
7001285290095
Y81 Inverter Replacement
501000096997
VD9175B Not Functioning Properly
04/07/2025
Corrective Action
Documents
501000098321
Incorrect information on 2270
05/04/2025
NH170037
Main Control Room CRV/EFT Systems
Drawings
NH170037
Main Control Room CRV/EFT System
Miscellaneous
Operating Instruction Placard for Railroad Doors in Reactor
Building
04/03/2025
25517-IA1
Instrument Air System Valve Exercise
270
Critical Safety System Checklist
3487
Drywell Entry Checklist
2000038003
9309, Changeout Selected CRDs - Maintenance
9007
Procedure for Moving Fuel Into, Out of, and Within the Core
FPIH-SAF01
Heat and Cold Stress Control Guidelines
Procedures
Ops Man D.205
Reactor and Core Components Handling Equipment
Work Orders
7001401230040
HPCI Steam Line Isolation Inboard, Manually Backseat
Valve for 900# Inspection
501000087225
MO 2012 Failed to Cycle as Expected
06/28/2024
501000094127
MO 2012 Past Operability
04/03/2025
501000096788
Recirculation Inboard Sample Valve Failed Diagnostic Test
04/02/2025
501000096997
VD9175B Not Functioning Properly
04/07/2025
Corrective Action
Documents
501000099278
Alt N2 Relief Valve Leaking
05/26/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Corrective Action
Documents
Resulting from
Inspection
501000099416
Calculation Error in AN2 Leak Analysis
05/29/2025
501000093404
HPCI Pressurizing Station Low Pressure
2/17/2024
Corrective Action
Documents
501000096952
104701 50.59 Review Required
04/04/2025
Drawings
NH36250
P&ID (Water Side) High Pressure Coolant Injection System
Procedures
8154, page 90
Installation of Electrical Jumpers/Block to Allow Stroking of
25520-IIC1
Reactor Coolant Pressure Boundary Leakage Test
2167
Plant Startup
2
204
Plant Shutdown
270
Critical Safety System Checklist
267
Tension RPV Studs
Procedures
292
Clean Reactor Pressure Vessel Head Flange And replace
ORings
Self-Assessments 602000022178
QF1123, Shutdown Safety Assessment Contingency
Planning Form
Corrective Action
Documents
501000098076
FLEX Equipment Missing
04/30/2025
Corrective Action
Documents
Resulting from
Inspection
501000098031
Inconsistent Guidance in 0137 Procedure
04/29/2025
Drawings
NX783467-7
Engineering
Evaluations
2000027874
QF0957, IST Evaluation / 96 Hour Evaluation / Rebaseline
05/08/2025
0003
Drywell, High Pressure Scram and Group 2, 3, & SCMT
Isolation Test and Calibration Procedure
0074
Control Rod Drive Exercise
0075
Control Rod Drive Coupling Test
Procedures
013702-06
X35A, X35B, X35C, X35D & X35E Primary Containment
Double-Gasketed Seals Local Leak Rate Test
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
013707A
Reactor Steam Supply Valves Leak Rate Testing
013727
TIP System Isolation Valves Pressure and Local Leak Rate
Test
214
Drywell-toSuppression Chamber Vacuum Breaker Cycle
Pressure and Leakage Test
25503-IA11
Core Spray Loop A Quarterly Pump and valve Tests
25507-IA2
Main Steam Isolation Valve Functional Checks Test
22
CRD-Withdrawal Stall Flow Test
1054
Control Rod Drive Normal Drive Timing Test
27
CRD-Insert Stall Flow Test
417103-PM
Off Gas Dilution Fan Damper Position
2000010244
456102-OCD, Uninterruptible Power Supply Inverter (Y81)
9019
Changeout Selected CRDs - Operations
9051
Changeout Selected CRDs-Operations
B.08.0805
Emergency Diesel Generator Start Up
B.09.1205
Reactor Protection Power Supplies
ESP-
MST013707E
Reactor Steam Supply Valve Line Leak Rate Test
G4A
NSP-MSC0137F
LLRT-LRM-Makeup Flow Method (Graftel 96237)
NSP-
MSC0137G
LLRT-LRM-Makeup Flow Method (Graftel EV)
OSP-RHR0564
LPCI Swing Bus Test
7000409790020
Emergency Diesel Generator Governor PMT
7000725210050
Stack Gas Dilution Fan Inlet Damper, VD8000J29
Post-Maintenance Test
7000770560140
EDG Voltage Regulator Replacement
7001140080020
Emergency Service Water Pump Discharge
7001205450035
Use P505 Portable Fire Pump to Pressurize Fire Header
04/27/2025
7001207010020
OTBD MSIV
70012072220040
RCIC Steam Line Inboard Isolation, MO 2075
Work Orders
7001207530030
0447, Primary Containment Personnel Airlock Interlock Test
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
7001208290040
HPCI Steam Line Isolation Outboard
7001224820070
05/13/2025
7001285290095
Y81 Inverter Replacement
700135316
7001360850070
Monticello Nuclear Generating Plant PMT/RTS Instructions
700138018
Repack AO280D
05/13/2025
7001380240110
Disassemble and Reassemble AO280A
05/03/2025
7001418960030
Miscellaneous
6/17/25 HAB Drill
Controller Guide
Full Scale Practice Drill
RWP 255119
Torus Dive and Filter Transfer Activities
RWP 255121
RWP 255126
RWCU HX Drain Line & RC Valve Replacements
ALARA Plans
RWP 255509
Control Rod Drives Changeout
501000090824
Elevated Dose Rates for Upcoming Work
10/07/2024
501000096909
Adverse Trend in RP Performance
04/04/2025
Corrective Action
Documents
501000097618
Trend in Radworker Performance
04/23/2025
501000097641
Three ARGOS Exit Gates Locks
04/23/2025
Corrective Action
Documents
Resulting from
Inspection
501000097946
Dose Measurement Set Points Higher
04/29/2025
Procedures
FPRP-SEN02
Radiological Work Planning and Controls
255119
1R32 - Torus - Diving - Inspect/Clean
255121
255126
1R32 - RWCU - Replace Drain Pipes & RC Valve
Radiation Work
Permits (RWPs)
255509
Work Orders
700152706
TBNWS Rad Mon High Alarm
03/23/2025
Reactor Chemistry Results
2/03/2024
Reactor Chemistry Results
03/11/2025
Reactor Chemistry Results
03/19/2025
71151
Miscellaneous
Monticello Nuclear Generating Plant - 2024 Annual Dose
Summary
04/01/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Monticello Nuclear Generating Plant - 2025 Annual Dose
Summary
04/01/2025
Electronic Dosimeter Transaction Log (>100 mrem Entries)
04/21/2025
QF0445
Safety System Functional Failures (April 01, 2024, through
March 31, 2025)
QF0445
RCS Leakage (April 01, 2024, through March 31, 2025)
Corrective Action
Documents
501000058393
FLEX Building Equipment
11/17/2021
Miscellaneous
2000036059
OSP-FIR1489, B.5.B/FLEX Equipment Inventory
Procedures
0118
Reactor Vessel Temperature Monitoring
25