IR 05000440/2025001
| ML25121A272 | |
| Person / Time | |
|---|---|
| Site: | Perry  |
| Issue date: | 05/02/2025 |
| From: | Sanchez-Santiago E NRC/RGN-III/DORS/RPB2 |
| To: | Penfield R Vistra Operations Company |
| Shared Package | |
| ML25063A193 | List: |
| References | |
| IR 2025001 | |
| Download: ML25121A272 (1) | |
Text
SUBJECT:
PERRY NUCLEAR POWER PLANT-INTEGRATED INSPECTION REPORT 05000440/2025001
Dear Rod Penfield:
On March 31, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Perry Nuclear Power Plant. On April 10, 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, Elba M. Sanchez Santiago, Chief Reactor Projects Branch 2 Division of Operating Reactor Safety Docket No. 05000440 License No. NPF-58
Enclosure:
As stated
Inspection Report
Docket Number:
05000440
License Number:
Report Number:
Enterprise Identifier:
I2025001-0060
Licensee:
Vistra Operations Company, LLC
Facility:
Perry Nuclear Power Plant
Location:
Perry, OH
Inspection Dates:
January 01, 2025 to March 31, 2025
Inspectors:
J. Beavers, Senior Resident Inspector
M. Domke, Senior Reactor Inspector
B. Jebbia, Operations Engineer
J. Nance, Operations Engineer
S. Orth, Technical Assistant
T. Ospino, Resident Inspector
B. Towne, Senior Resident Inspector
Approved By:
Elba M. Sanchez Santiago, Chief
Reactor Projects Branch 2
Division of Operating Reactor Safety
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting an integrated inspection at Perry Nuclear Power 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
Type Issue Number Title Report Section Status LER 05000440/2024004-00 LER 2024004-00 for Perry Nuclear Power Plant,
Division 3 Diesel Generator Inoperable due to Low Output Voltage Resulting in Loss of Safety Function 71153 Closed LER 05000440/2024005-00 LER 2024005-00 for Perry Nuclear Power Plant,
Division 3 Diesel Generator Inoperable due to Failure of the Right Bank Air Start Motor 71153 Closed
PLANT STATUS
Unit 1 began the inspection period at rated thermal power. On January 10, 2025, the unit began lowering power slowly from 100 percent to 90 percent through the end of the month due to emergent non-safety system issues. After completing repairs on February 1, 2025, power was reduced to 65 percent to adjust rod line. Power was then restored to full power on February 2, 2025. On February 26, 2025, the unit was shut down for different, emergent, non-safety system repairs. After completing repairs, the unit was restarted on March 9, 2025. Power was increased to 84 percent when the licensee encountered another non-safety system issue. The unit remained at 84 percent power until it was shut down for refueling outage 20 on March 16,
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 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.
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 severe weather, extreme cold weather, on January 21 and 22, 2025
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) Control rod drive system on March 10, 2025
- (2) Low pressure core spray on March 31, 2025
- (3) Division 2 emergency diesel generator on March 31, 2025
71111.05 - Fire Protection
Fire Area Walkdown and Inspection Sample (IP Section 03.01) (8 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) Control complex on January 21, 2025
- (2) Unit 1 turbine power building on February 10, 2025
- (3) Fuel handling building on February 21, 2025
- (4) Unit 1, division 1, 2, and 3 4.16 KV and 480 V switchgear rooms on February 27 and 28, 2025
- (5) Emergency service water pump house on February 28, 2025
- (6) High pressure core spray pump room and high pressure core spray valve room on March 1, 2025
- (7) Unit 1 containment on March 25, 2025
- (8) Unit 1 drywell on March 31, 2025
71111.06 - Flood Protection Measures
Flooding Sample (IP Section 03.01) (1 Sample)
- (1) The inspectors evaluated internal flooding mitigation protections in the: emergency service water pump house, Unit 1 auxiliary building, and general power block
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 by reviewing the following examinations from March 17, 2025 to March 28, 2025:
(1)
1. Volumetric examination of American Society of Mechanical Engineers (ASME)
class 1 small bore piping program pipe to elbow welds 1N220106, 1N220107, and 1N220108 in the main, reheat, extraction, and miscellaneous drain system.
2. Visual examination of in-vessel bolt 1B13CSS-UPR187SB-BOLT212
3. Visual examination of in-vessel jet pump wedge assembly 1B13JPWD1P18
4. Visual examination of in-vessel core shroud weld 1B13CS-H8
5. Pressure boundary weld number 3 of work order WO200847836 pipe to elbow
butt weld for the reactor water cleanup (RWCU) filter Demin/bypass isolation valve replacement
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 the plant forced outage shutdown on March 5, 2025
Licensed Operator Requalification Training/Examinations (IP Section 03.02) (1 Sample)
- (1) The inspectors observed and evaluated crew simulator performance on February 3, 2025
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) Circulating water system failure on February 26, 2025
- (2) Control rod drive system pump 'A' failure on March 9, 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) Reactor recirculating pump 'A' flow control valve failure on January 7, 2025
71111.13 - Maintenance Risk Assessments and Emergent Work Control
Risk Assessment and Management Sample (IP Section 03.01) (3 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) Maintenance risk assessment during solids collection filter shipping transfer in fuel handling building on February 14, 2025
- (2) Maintenance risk assessment during circulating water system leakage and initiating event sequences on February 23, 2025
- (3) Shutdown maintenance risk assessment during single source offsite power available and reduced inventory on March 18, 2025
71111.15 - Operability Determinations and Functionality Assessments
Operability Determination or Functionality Assessment (IP Section 03.01) (4 Samples)
The inspectors evaluated the licensees justifications and actions associated with the following operability determinations and functionality assessments:
- (1) Operability determination of division 1 emergency diesel generator due to alarm panel issues
- (2) Operability determination of 'A' reactor recirculating loop due to flow mismatch
- (3) Operability determination of drywell radiation monitor inboard isolation valve failed stroke time
- (4) Past operability determination related to the failure of the standby liquid control pump 'A'
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) Temporary modification of the reactor recirculating pump 'A' flow control valve control mechanism
- (2) Permanent modification of the shroud head stud assembly modification
- (3) Permanent modification of the Unit 2 Startup transformer differential scheme modification
71111.20 - Refueling and Other Outage Activities
Refueling/Other Outage Sample (IP Section 03.01) (1 Sample 1 Partial)
- (1) The inspectors evaluated forced maintenance outage activities from February 26, 2025, to March 10, 2025 (2)
(Partial)
The inspectors evaluated refueling outage activities from February 24, 2025, to March 31, 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) (2 Samples)
- (1) Reactor recirculating pump 'A' flow control valve temporary modification on February 1, 2025
- (2) Source range monitor 'B' on March 7, 2025
Surveillance Testing (IP Section 03.01) (3 Samples)
- (1) Fuel pool cooling and cleanup system valve operability test on February 6, 2024
- (2) Fuel movement review during the RFO20 March 25, 2025
- (3) Standby liquid control train 'A' squib valve test on March 26, 2025
Inservice Testing (IST) (IP Section 03.01) (1 Sample)
- (1) Division 1 emergency core cooling system (ECCS) integrated test on March 31,
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 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) (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 at the alternate/outage control point
- (2) Workers exiting the radiologically controlled area at the main (Unit 1) control point
Radiological Hazards Control and Work Coverage (IP Section 03.04) (3 Samples)
The inspectors evaluated the licensee's control of radiological hazards for the following radiological work:
- (1) Reactor disassembly activities under radiation work permit (RWP) 250901
- (2) Undervessel activities under RWP 250518
- (3) Inboard isolation valve replacement under RWP 250444 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 (VHRAs):
- (1) Inclined fuel transfer system access at valve room and fuel handling building floor plug
- (2) Fuel pool cooling and cleanup (FPCC) filter and demineralizer 'A' and 'B' (access door)
- (3) FPCC filter and demineralizer 'C' and 'D' (access door)
- (4) Impacted areas from contamination of the containment and drywell ventilation system (M14)
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
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) January 1 through December 31, 2024 IE03: Unplanned Power Changes per 7000 Critical Hours Sample (IP Section 02.02) (1 Sample)
- (1) January 1 through December 31, 2024
IE04: Unplanned Scrams with Complications (USwC) Sample (IP Section 02.03) (1 Sample)
- (1) January 1 through December 31, 2024
71153 - Follow Up of Events and Notices of Enforcement Discretion Event Follow Up (IP Section 03.01)
- (1) The inspectors evaluated a circulating water system underground piping leak and the licensees response on February 19, 2025
- (2) The inspectors evaluated the automatic start of the division 3 emergency diesel generator on March 29, 2025
Event Report (IP Section 03.02) (2 Samples)
The inspectors evaluated the following licensee event reports (LERs):
- (1) LER 05000440/2024004-00, Division 3 Diesel Generator Inoperable due to Low Output Voltage Resulting in Loss of Safety Function, ADAMS Accession No. ML25055A256. The circumstances surrounding this LER and inspection conclusions are documented in Inspection Report 05000440/2024004 under Inspection Results Section 71153. This LER is Closed.
- (2) LER 05000440/2024005-00, Division 3 Diesel Generator Inoperable due to Failure of the Right Bank Air Start Motor, ADAMS Accession No. ML25023A193. The circumstances surrounding this LER and inspection conclusions are documented in Inspection Report 05000440/2024004 under Inspection Results Section 71153. This LER is Closed.
INSPECTION RESULTS
Observation: Circulating Water System Underground Piping Leak 71153 On February 19, 2025, the Perry Nuclear Power Plant identified an underground piping leak in the protected area of the plant near the cooling towers. Off normal instruction, Leak in Underground Piping, was entered, and the plant was verified as stable with no immediate safety concerns. The source of the leak was determined to be the non-safety circulating water system that transports rejected heat from the turbine condenser to the cooling tower. The resident inspector office (RIO), regional radiological protection inspectors, and material/structural inspectors evaluated: nuclear safety concerns with initiating events and potential affected nearby equipment; industrial safety concerns related to voiding in the area and ground; and environmental concerns regarding the movement of water and potential contamination onsite and unmonitored effluent drain issues offsite. Based on their review the inspectors did not identify any safety concerns in any of these areas. Specifically, the licensees flooding analysis ruled out safety system impact for any likely progressions of the water. Ground radar to a depth of five feet did not detect any voids beyond the immediate leakage source. A chemical/radiation sampling program did not detect tritium or other chemistry/radiological transport issues on site or in the adjacent groundwater effluent paths to the environment. The RIO also monitored the licensees implementation of a variety of plant procedures and decision-making guidelines to address the initial, then degrading, conditions of the leak. No findings of significance were identified as a result of this review.
On February 26, 2025, the licensee directed a controlled shutdown of the reactor plant to repair the leak. On March 9, 2025, following the completion of repairs on the circulating water system, the reactor plant was restarted with intention to operate until the planned refueling outage starting March 16, 2025.
This inspection did not include reviewing any causal nor long term corrective action efforts.
Upon completion of the event investigation, the RIO has planned a problem identification and resolution sample to address these areas.
The NRC did determine this event warranted consideration for a reactive inspection. The NRC evaluated the event and documented its initial assessment in Management Directive 8.3 Decision Documentation for Reactive Inspection (ML25063A236). The NRC concluded a reactive inspection was not warranted for this issue because there were no adverse impacts on safety equipment or functions and it did not cause an initiating event.
Observation: Automatic Start of the Division 3 Emergency Diesel Generator 71153 On March 29, 2025, Unit 1 was in Mode 5 during a refueling outage with a single offsite power source available through the Unit 1 startup transformer. During testing of the Unit 2 startup transformer, power was disrupted to the available but inoperable division 3 shutdown safety electrical bus. This caused an actuation of the division 3 emergency diesel generator (3DG) system and entries into off normal operating procedures for the following systems:
electrical power, non-safety service water, and the plant air system.
The Perry resident inspector office evaluated both operator and equipment response to the event and did not identify any issues with the equipment and operator actions. Also, no loss of key safety function was identified to include no loss of offsite power nor loss of decay heat removal. The plant electrical, non-safety service water, and air systems were impacted but were subsequently stabilized and returned to pre-event status. This event was reportable in accordance with 10 CFR 72(b)(3)(iv)(A), event that results in valid actuation of any system, i.e., 3DG and logged as NRC Event Notification
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On April 10, 2025, the inspectors presented the integrated inspection results to R. Penfield, Site Vice President, and other members of the licensee staff.
- On March 20, 2025, the inspectors presented the radiation protection inspection results to D. Hartigan, Director of Nuclear Maintenance, and other members of the licensee staff.
- On March 31, 2025, the inspectors presented the inservice inspection results to R. Penfield, Site Vice President, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Procedures
ONI-R362
Extreme Cold Weather
SOI-C11(CRDH)
Control Rod Drive Hydraulic System
SOI-E21
Low Pressure Core Spray System
Procedures
SOI-R43
Division 1 and 2 Diesel Generator System
FPI0CC
Control Complex
FPI0EW
Emergency Service Water Pumphouse
FPI0FH
Fuel Handling Building
FPI1AB
Auxiliary Building Unit 1
FPI1RB
Reactor Building
Fire Plans
FPI1TPB
Turbine Power Building Unit 1
Corrective Action
Documents
CR202501304
Copious Groundwater Intrusion through Turbine Building
593' Penetrations
2/27/2025
Corrective Action
Documents
CR202301964
Three Relevant Indications Identified During Ultrasonic
Examination of Socket Welds
03/15/2023
1B13 JP18 WD1
MTS2
In-Vessel Visual Inspection
03/26/2025
1B13 SHD OD
H08 340000_2C
In-Vessel Visual Inspection
03/26/2025
NDE Reports
1B13CSS-
UPR187SB-
BOLT212_2A
In-Vessel Visual Inspection
03/26/2025
200773644
LPCI C Injection Check Valve
03/19/2023
200847836
RWCU Filter Demin/Bypass Valve PY1G33F0044
04/07/2023
200850039
Testable Check Valve
04/08/2023
200909701
Fuel Pool Cooling and Cleanup System
04/07/2023
Work Orders
200910432
Replace Flex Hose for 1B21F0047B
03/31/2023
Procedures
NORM-OP1002
Conduct of Operations
CR202500088
Flow Control Valve Moving Independent of Operator Input
01/07/2025
Corrective Action
Documents
CR202501109
ONI-ZZZ6 Entry for Leak in Underground Piping by Circ
Water Pumphouse
2/19/2005
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
CR202501600
CRD Pump A Outboard Bearing Inboard Sight Glass
Leaking Lubricating Oil
03/09/2025
CR202501609
CRD Pump A Failed Post Maintenance Test
03/09/2025
Work Orders
200965050
Rotary Variable Differential Transducer
CE202501934
SLC Pump A Relief Valve (PY1C41F0029A) Failed Post-
Service Testing
03/20/2025
Corrective Action
Documents
CR202501060
Solids Collection Filter Liner Lid Does Not Fit Liner
2/18/2025
G51
Solids Collection Filter Shipping Transfer
2/10/2025
NOP-OP1005
Shutdown Defense in Depth
ONI-ZZZ6
Leak in Underground Piping
PAP1925
Shutdown Defense in Depth Assessment and Management
Procedures
TROP035
Handling Procedure for Transport Cask Model 8120B
Certificat of Compliance Number 9168
CR202500538
Division 1 Emergency Diesel Generator Alarm Panel Locked
Alarms
01/26/2025
CR202501189
Drywell Radiation Monitor Inboard Suction Isolation Failed
Stroke Time Close per SVI-D17T2001
2/23/2025
Corrective Action
Documents
CR202501934
SLC Pump A Relief Valve (PY1C41F0029A) Failed
Post-Service Testing
03/19/2025
Miscellaneous
February 2, 2025
Operator Logs
February 2, 2025 Operator Logs
2/02/2025
251003-000
Install Circuit to Facilitate Controllability of Flow Control
Valve A due to Degraded RVDT
Engineering
Changes
ECP 210194-002
Addition of Slip-Over Current Transformers (CTs) to the Unit
Startup Transformer
Engineering
Evaluations
GEH Engineering
Evaluation
007N6957,
Addition of Slip-Over Current Transformers (CTs) to the
Unit 2 Startup Transformer
Miscellaneous
1R20 SDDID
1R20 Shutdown Defense in Depth Report
CR202500648
PMT Failure During Implementation of TM 251003, Install
Circuit to Facilitate Controllability of Flow Control Valve 'A'
Due to Degraded RVD
01/30/2025
CR202501279
'B' Source Range Monitor Indication Erratic
2/26/2025
Corrective Action
Documents
CR202501672
'A' Recirc Loop Flow Control Valve As Left Values Outside
LAIZ
03/11/2025
FTI-D0009
Use of the Fuel Movement Checklist
03/25/2025
SVI-C41T2002
Standby Liquid control System Operability
SVI-G41T2002
Fuel Pool Cooling and Cleanup System Valve Operability
Test
Procedures
SVI-R43T700A
Division 1 ECCS Integrated Test
200856275
'A' Reactor Recirc Flow Control Valve Rotary Variable
Differential Transformer Replacement
2/28/2025
200914366
03/26/2025
Work Orders
200957391
'B' Source Range Monitor Indication Erratic
CR202409520
Turbine Crane Project Worker Received an Unbriefed Dose
Rate Alarm
2/12/2024
CR202409540
Turbine Crane Project Worker Received an Unbriefed Dose
Rate Alarm
2/14/2024
CR202500493
The 2024 Safety Conscious Work Environment (SCWE)
Survey Results for Radiation Protection
01/23/2025
Corrective Action
Documents
CR202501891
Contamination Found in Clean Area
03/18/2025
Procedures
NOP-OP4107
Radiation Work Permit (RWP)
PY-
M2025031845
(Map 1)
H60001 - General Hallway Access
03/18/2025
Radiation
Surveys
PY-
M2025031845
(Map 2)
H6002EW - DC/5A and 5B/6A and 6B HTR Room
03/18/2025
PY-
M2025031845
(Map 3)
H5800307 - General Hallway and Build Heating Pump
03/18/2025
Radiation
Surveys
PY-
M202503194
DW576/Undervessel Floor
03/19/2025
250444
1R20 - 1G33F0037/1G33F0038 Valve Replacement
Activities - LHRA
250518
IR20 - Undervessel Activities
Radiation Work
Permits (RWPs)
250901
1R20 - Reactor Disassembly Activities
Self-Assessments ATA202413299
Pre-NRC Inspection - Radiological Hazard Assessment and
Exposure Controls
2/15/2024
PI Monthly Data
IE01: Unplanned Scrams per 7000 Critical Hours January 1
through December 31, 2024
PI Monthly Data
IE03: Unplanned Power Changes per 7000 Critical Hours
January 1 through December 31, 2024
71151
Miscellaneous
PI Monthly Data
IE04: Unplanned Scrams with Complications January 1
through December 31, 2024
CR202501109
ONI-ZZZ6 Entry for Leak in Underground Piping by Circ
Water Pumphouse
03/19/2025
Corrective Action
Documents
CR202502265
Loss of L20 Bus during Breaker Trip Check Testing
03/29/2025