IR 05000346/2025010
| ML25163A132 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 06/16/2025 |
| From: | Sanchez-Santiago E NRC/RGN-III/DORS/RPB2 |
| To: | Tony Brown Vistra Operations Company |
| References | |
| IR 2025010 | |
| Download: ML25163A132 (1) | |
Text
SUBJECT:
DAVIS-BESSE NUCLEAR POWER STATION - BIENNIAL PROBLEM IDENTIFICATION AND RESOLUTION INSPECTION REPORT 05000346/2025010
Dear Terry Brown:
On May 8, 2025, the U.S. Nuclear Regulatory Commission (NRC) completed a problem identification and resolution inspection at your Davis-Besse Nuclear Power Station and 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.
The NRC inspection team reviewed the stations problem identification and resolution program to confirm that the station was complying with NRC regulations and licensee standards. Based on the samples reviewed, the team determined that your program complies with NRC regulations and applicable industry standards such that the Reactor Oversight process can continue to be implemented.
The team also evaluated the stations effectiveness in identifying, prioritizing, evaluating, and correcting problems, reviewed licensee audits and self-assessments, and its use of industry and NRC operating experience information. The results of these evaluations are in the enclosure.
Finally, the team reviewed the stations programs to establish and maintain a safety-conscious work environment and interviewed station personnel to evaluate the effectiveness of these programs. Based on the teams observations and the results of these interviews, the team found no evidence of challenges to your organizations safety-conscious work environment. Your employees appeared willing to raise nuclear safety concerns through at least one of the several means available.
One finding of very low safety significance (Green) is documented in this report. This finding did not involve a violation of NRC requirements.
If you disagree with a cross-cutting aspect assignment or a finding not associated with a regulatory requirement in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your disagreement, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555-0001; with copies to the June 16, 2025 Regional Administrator, Region III; and the NRC Resident Inspector at Davis-Besse Nuclear Power Station.
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. 05000346 License No. NPF-3
Enclosure:
As stated
Inspection Report
Docket Number:
05000346
License Number:
Report Number:
Enterprise Identifier:
I-2025-010-0000
Licensee:
Vistra Operations Company, LLC
Facility:
Davis-Besse Nuclear Power Station
Location:
Oak Harbor, OH
Inspection Dates:
April 21, 2025 to May 08, 2025
Inspectors:
R. Cassara, Senior Resident Inspector
R. Ng, Senior Project Engineer
J. Robb, Operations Engineer
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 a biennial problem identification and resolution inspection at Davis-Besse Nuclear Power Station, 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
Failure to Perform an Operability Evaluation Cornerstone Significance Cross-Cutting Aspect Report Section Barrier Integrity Green FIN 05000346/2025010-01 Open/Closed
[P.2] -
Evaluation 71152B The inspectors identified a finding of very low safety significance (green) for the licensees failure to perform an operability evaluation in accordance with procedure NORM-OP-1009,
SRO Review of Condition Reports. Specifically, the licensee incorrectly determined that exceeding the core lift criteria did not have a functional impact on the SSC because they believed that the suspected cause of the flow calculation changes was due to temperature inputs to the calculations drifting. The licensee did not perform an operability determination to evaluate the impact of the temperature drift to the calculation methodology for both the core lift and the departure of nucleate boiling (DNB) safety analysis.
Additional Tracking Items
None.
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 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.
OTHER ACTIVITIES - BASELINE
71152B - Problem Identification and Resolution Biennial Team Inspection (IP Section 03.04)
- (1) The inspectors performed a biennial assessment of the effectiveness of the licensees Problem Identification and Resolution program, use of operating experience, self-assessments and audits, and safety conscious work environment.
- Problem Identification and Resolution Effectiveness: The inspectors assessed the effectiveness of the licensees Problem Identification and Resolution program in identifying, prioritizing, evaluating, and correcting problems. The inspectors also conducted a five-year review of the reactor coolant pump issues. The inspectors also reviewed the corrective actions for selected NRC non-cited violations and findings.
- Operating Experience: The inspectors assessed the effectiveness of the licensees processes for use of operating experience.
- Self-Assessments and Audits: The inspectors assessed the effectiveness of the licensees identification and correction of problems identified through audits and self-assessments.
- Safety Conscious Work Environment: The inspectors assessed the effectiveness of the stations programs to establish and maintain a safety-conscious work environment.
INSPECTION RESULTS
Assessment 71152B Assessment of the Corrective Action Program Based on the samples reviewed, the inspectors concluded the licensee's implementation of the Corrective Action Program (CAP) was generally effective and supported nuclear safety.
Effectiveness of Problem Identification:
Based on the samples reviewed, the inspectors determined that the licensee continued to identify issues at a low threshold and appropriately entered these issues into the CAP. The inspectors also determined the licensee usually entered problems into the CAP, timely, completely and accurately. The inspectors observed that issues were being identified by all levels of organization and with varying degrees of safety, security, or radiological significance.
Some deficiencies were identified by external organizations, including the NRC, and they were subsequently entered into the CAP for resolution. The licensee also utilized a number of CAP support processes to identify problems, including the self-assessment and audit processes and the Operating Experience (OE) Program. For example, the inspectors noted that the licensee periodically performed departmental self-assessments and Nuclear Oversight audits to identify issues in station programs and processes. The identified deficiencies and improvement opportunities were entered into the CAP for resolution.
Similarly, the licensee screened issues from both the NRC and from industry OE programs and entered them into the CAP for evaluation when they were applicable to the station. The inspectors determined the licensee was generally effective at trending low-level issues and taking appropriate corrective actions to prevent more significant problems from developing. In addition, the licensee had conducted effectiveness reviews and used the CAP to document instances in which previous corrective actions were ineffective or were inappropriately closed.
The Inspectors performed a review of the reactor coolant pump issues over the last 5 years. The inspectors focused on any potential recurring or age-related issues that were not identified by the licensee. As part of this review, the inspectors reviewed selected corrective action program documents, and interviewed the system engineer. The inspectors concluded that deficiencies and concerns were identified and entered into the CAP at a low threshold.
Issues with the pumps were characterized and addressed appropriately. The inspectors did not identify any programmatic deficiencies in this area.
Effectiveness of Prioritization and Evaluation of Issues:
Based on the samples reviewed, the inspectors determined that licensee performance was generally effective at prioritizing and evaluating issues commensurate with the safety, security or radiological significance of the identified problem. The licensee utilized a multi-discipline team consisting of department directors and managers to review the condition report categorization, evaluation method selection, and other actions would adequately address the causes and extent of condition when applicable. Upon completion of the evaluation or actions, the Corrective Action Review Board reviewed those products to ensure they met the CAP requirements. During the Management Review Board and Corrective Action Review Board meetings the inspectors observed, licensee staff were generally thorough and intrusive in reviewing issues. The inspectors also observed healthy dialogues and good interactions among the members of the respective groups. Licensee staff were prepared and challenged each other on disposition of the identified conditions. Actions were prioritized based on the safety, security or radiological significance of the issues. In general, once a degraded or non-conforming issue was identified, the CAP process was effective in directing equipment operability or functionality reviews. The inspectors did identify an issue related to an operability review, which was documented in the Results Section of this report.
Effectiveness of Corrective Actions:
Based on the samples reviewed, the inspectors determined the licensee was generally effective in corrective action implementation. In general, corrective actions for deficiencies that were safety, security or radiological significant were tracked to completion in a timely manner. Problems requiring the performance of a causal evaluation were resolved in accordance with CAP requirements. The inspectors sampled assignments associated with violations that were identified by the NRC previously and those associated with various significances. The inspectors determined that the corrective actions sampled were generally effective and timely and addressed the adverse conditions.
Assessment 71152B The Use of Operating Experience Based on the samples reviewed, the team determined that the licensees performance in the use of operating experience (OE) was generally effective. The licensee screened industry and NRC OE information for applicability to the station. When applicable, condition reports were written, and actions were developed and implemented to prevent similar issues from occurring. Operating experience lessons learned were communicated and incorporated into plant operations. The inspectors observed OE information being used in daily activities, such as pre-job briefs, as well as issue reviews and investigations. The licensee is also cognizant on generating OE lesson learned from issues encountered in the plant. The inspectors did not identify any issue of significance in this area.
Assessment 71152B Self-Assessments and Audits Based on the samples reviewed, the inspectors determined that the licensees performance of self-assessments and audits was generally effective. The licensee performed department self-assessments and Quality Assurance audits throughout the organization on a periodic basis. These self-assessments and audits were generally effective at identifying issues and enhancement opportunities at an appropriate threshold. The self-assessments and audits reviewed by the inspectors identified issues that were not previously known, including issues regarding the CAP itself. Those issues were generally captured, and actions were generally taken by the licensee through the CAP for resolution. The inspectors did not identify any issue of significance in this area.
Assessment 71152B Safety Conscious Work Environment The inspectors reviewed the results of the Davis-Besse safety culture survey that was conducted in November 2024. The inspectors noted the survey documented negative staff responses regarding the Employee Concerns Program (ECP). The inspectors also noted that there was a high number of negative responses in several departments regarding confidence in the CAP to prioritize, investigate, and resolve issues. As a result, the inspectors reviewed licensee actions to address the negative survey trends. The inspectors also performed individual interviews of a representative cross-section of licensee personnel, including individual contributors, supervisors and contractors from various departments. The inspectors also interviewed the ECP manager and reviewed selected ECP case files. A total of 23 licensee personnel were interviewed during this inspection.
Based on the interviews and a review of licensee actions, the inspectors determined licensee personnel believed that they could raise nuclear safety, security or radiological issues through multiple channels including ECP without fear of retaliation. Licensee staff also believe that the CAP effectively addresses issues important to nuclear safety. However, some licensee staff have expressed frustration with the CAP process on resolving low-level issues partly because they are not aware of all the considerations and constrains going into the decisions. Similarly, several licensee staff members were not fully aware of the ECP or how they could utilize the program. The inspectors determined that the ongoing licensee efforts to improve communications should address these negative responses. The inspectors found no evidence of challenges to the safety conscious work environment at Davis-Besse.
Failure to Perform an Operability Evaluation Cornerstone Significance Cross-Cutting Aspect Report Section Barrier Integrity Green FIN 05000346/2025010-01 Open/Closed
[P.2] -
Evaluation 71152B The inspectors identified a finding of very low safety significance (green) for the licensee's failure to perform an operability evaluation in accordance with procedure NORM-OP-1009, SRO Review of Condition Reports. Specifically, the licensee incorrectly determined that exceeding the core lift criteria did not have a functional impact on the SSC because they believed that the suspected cause of the flow calculation changes was due to temperature inputs to the calculations drifting. The licensee did not perform an operability determination to evaluate the impact of the temperature drift to the calculation methodology for both the core lift and the departure of nucleate boiling (DNB) safety analysis.
Description:
In May 2022, the licensee identified an increasing trend in RCS flow rate calculated per DB-SP-03358, RCS Flow Rate Test. This reactor coolant system (RCS) flow rate test is a Technical Specification (TS) surveillance that is required to be performed every 18 months.
The purpose of the surveillance was to verify the TS minimum RCS flow limit rate limit.
Additionally, it serves to verify the core lift analysis maximum RCS flow rate limit, which is not a TS controlled parameter. The method used is to perform a secondary side heat balance to calculate the RCS flow rate. The surveillance is also used to verify that plant RCS flow instruments are within acceptable tolerance for other TS surveillances. The TS minimum flow rate limit is to ensure that the initial condition assumed in the safety analysis for DNB is maintained. Although the core lift criteria is not a TS limit, it precludes the fuel assembly liftoff during postulated Condition I and Condition II events. Conditional I events are normal operations such as startup, shutdown or refueling. Condition II events are plant transients such as loss of feedwater or control rod drop. These flow limits protect the fuel rod fission product barrier. At the time the trend was identified, both acceptance criteria were satisfied but the licensee implemented a number of actions to investigate the increasing trend.
In April 2024, during the next surveillance, the RCS flow rate calculated from one of the two channels exceeded the core lift analysis maximum RCS flow limit. The licensee initiated condition report CR-2024-2942 for this condition. Per procedure NORM-OP-1009, SRO Review of Condition Reports, states that Entry into the Operability Determination (OD)process is contingent upon the Deficient Condition satisfying the Three Required Entry Criteria (TRC). The licensee at the time determined that Criterion 1, Does the deficient condition affect a TS SSC installed in an operating unit? was met. The licensee determined that Criteria 2, Does the deficient condition have a functional impact on the SSC? This includes the ability to perform required functions under postulated, off-normal design conditions was not met because the licensee believed there was reasonable assurance that the core lift analysis was met and therefore, the RCS and fuel would continue to perform their functions. This was based on the RCS radiochemistry and no indications of fuel defects or fuel failure and diverse indication of acceptable flow. As such, Criterion 3, Is the functional impact of the deficient condition substantive? did not need to be answered. Therefore, the licensee did not perform an operability determination.
In May 2025, the inspectors reviewed the condition report associated with this issue. Based on the review, the inspectors determined that exceeding the core lift criteria had a functional impact on the fuel assembly during postulated, off-normal design conditions. Specifically, given that the licensee believed at the time that the suspected cause of the flow calculation changes was due to temperature inputs to the calculations drifting, the inspectors determined that the impact to the calculation methodology was not evaluated and could impact both the core lift and the DNB safety analyses. The inspectors concluded that both Criterion 2 and 3 should have been answered yes and an operability determination be performed.
Corrective Actions: The licensee entered this issue into the CAP and plans to revise the core lift analysis to address the issue.
Corrective Action References: CR-2025-03538, Inadequate Detail in CR-2024-04075 to Capture Basis for Meeting Technical Specification Requirements
Performance Assessment:
Performance Deficiency: The inspectors determined that the failure to perform an operability evaluation in accordance with NORM-OP-1009 was a performance deficiency that was reasonably within the licensees ability to foresee and correct and should have been prevented. Specifically, the licensee incorrectly determined that exceeding the core lift criteria did not have a functional impact on the SSC because they believed that the suspected cause of the flow calculation changes was due to temperature inputs to the calculations drifting.
However, the impact from the temperature drift to the calculation methodology was not evaluated and could impact both the core lift and the DNB safety analyses.
Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the SSC and Barrier Performance attribute of the Barrier Integrity cornerstone and adversely affected the cornerstone objective to provide reasonable assurance that physical design barriers protect the public from radionuclide releases caused by accidents or events. Specifically, since the same calculation is used to verify both the maximum core lift analysis limit and the minimum RCS flow limit, the licensee did not thoroughly evaluate the impact to both safety analysis methodology, which is directly related to the fuel barrier performance.
Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The inspectors screened the issue to Green because the inspectors answered all the Fuel Cladding Integrity questions in IMC 0609 Exhibit 3 - Barrier Integrity Screening Questions no.
Cross-Cutting Aspect: P.2 - Evaluation: The organization thoroughly evaluates issues to ensure that resolutions address causes and extent of conditions commensurate with their safety significance. Specifically, the licensee did not thoroughly evaluate the cause of the RCS flow exceeding the core lift limit and therefore, did not consider the full impact to the calculation methodology of both safety analysis limits.
Enforcement:
Inspectors did not identify a violation of regulatory requirements associated with this finding.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On May 8, 2025, the inspectors presented the biennial problem identification and resolution inspection results to Terry Brown and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
ATA-2023-2857
NRC Cyber Security Inspection IP71130.10 Self-Assessment
2/13/2023
CR-2017-11317
Cyber Security Program: Control Deficiencies
11/17/2017
CR-2017-11807
Cyber Security Program: Control Deficiencies
11/30/2017
CR-2018-10472
Error in the Auxiliary Building Tornado Differential Pressure
Model
11/27/2018
CR-2020-03138
Received L787 RCP 1-1 MTR LWR BRG OIL LVL High
Computer Point
04/12/2020
CR-2020-04242
System Monitoring - Reactor Coolant Pump (RCP) 1-2 Seal
Cavity Pressure Trends
05/14/2020
CR-2021-02678
21 Cyber Inspection: Untimely Implementation of
CA-2017-11807-001
04/08/2021
CR-2021-04888
Cyber: Implement the New Baseline Configuration Auditing
Requirements of NOBP-SS-1205, Cyber Security
Configuration Control
06/23/2021
CR-2021-05292
RCP 1-2 Third Stage Cavity Pressure Reading Lower than
Normal
07/10/2021
CR-2021-07196
Rising Trend RCP 1-2 Drinking Bird Counts
09/25/2021
CR-2021-08974
Service Water Baseline Test Engineering Review
DB-PF-03216
11/24/2021
CR-2021-09282
NRC TI inspection: DB-OP-06313 Procedure Enhancement
Observation for Open Phase Condition
2/07/2021
CR-2022-00817
HPI Train 1 Pressure Rising Following MU Valve Stroke
2/03/2022
CR-2022-03833
Increasing Trend for Reactor Coolant System Flow Rate
Calculated per DB-SP-03358, RCS Flow Rate Test
05/04/2022
CR-2022-09409
RCP Motor Oil Drain Tank Level High
2/11/2022
CR-2022-09426
22 NRC Radiation Protection Baseline Inspection: NRC
Identified Tritium Sampling Basis Methodology Was Not
Determined
2/12/2022
CR-2022-09681
RCP 1-2 Third Stage Seal Downward Pressure Trend and
Elevated Seal Leakage Rate
2/21/2022
Corrective Action
Documents
CR-2023-02245
Performance Gap Analysis Requested for Instrument and
Control Maintenance Regarding Nuclear Instrument
03/24/2023
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Maintenance
CR-2023-02453
23 Security Training Inspection, NRC Finding
03/30/2023
CR-2023-02623
Zip Drive Disk Discovered at PAF Entrance Area
04/04/2023
CR-2023-02948
Conditions outside of Original Design Tolerance Identified
While Mapping the Cooling Tower
04/12/2023
CR-2023-03338
Ground Settling Aggregate Review Enhancements
04/21/2023
CR-2023-03771
MS-C-23-08-20: Prep - Utilization of a Cancelled Documents
by Access Authorization
05/04/2023
CR-2023-04596
SBODG Cylinder 20 Rocker Arm Shaft Cap Broken
06/05/2023
CR-2023-04687
SBODG Extended Unavailability Time due to Low Fuel Oil
Level
06/08/2023
CR-2023-04801
Call Tree Individual Did Not Respond to Unannounced
Call-In Dill
06/14/2023
CR-2023-04944
Insufficient Documentation of Evaluations for Sink
Holes/Areas of Settlement Within 15 feet of Safety-Related
Structures
06/21/2023
CR-2023-05000
Failure to address adverse condition (Fire Protection piping
misalignment) in Corrective Action Program
06/22/2023
CR-2023-05298
Trending for Self Powered Neutron Detectors
07/03/2023
CR-2023-05430
Replacement Door 458 Incorrect Size
07/11/2023
CR-2023-05666
FME: Retaining Pin Stuck Between Fuel Pins of Fuel
Assembly
07/20/2023
CR-2023-05671
SCBA-029 Failed Monthly Performance Test
07/20/2023
CR-2023-05829
RC Loop 2 Hotleg NR Temp (PPCS:T730) Appears High
07/26/2023
CR-2023-05945
Area of Concern (AOC) Issued to Davis-Besse Site
Protection due to Recent Trend of Safety and Human
Performance
07/31/2023
CR-2023-06048
MS-C-23-07-08: FINDING: M&TE Usage Not Tracked in
08/03/2023
CR-2023-06564
23 WANO AFI: NP.1 Workers are Not Consistently
Adhering to Human Performance Standards during Work
Activities.
08/23/2023
Corrective Action
Documents
CR-2023-06732
- 1 Emergency Diesel Generator (#1 EDG) Monthly Water
Jacket Iron Analysis is Trending Higher Than Typical Values.
08/29/2023
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
CR-2023-07574
RCP 1-1 Drinking Bird Counter Stopped Moving
10/07/2023
CR-2023-07667
RC Loop 2 Hot Leg NR Temp Appears High (PPCS:T730)
10/11/2023
CR-2023-07692
Degrading Seal Parameters for RCP 1-2
10/11/2023
CR-2023-07894
AFPT 2 Governor is Hunting Excessively at the HSS.
10/20/2023
CR-2023-09194
RPS Channel 1 RCS Flow Mode Configured to Incorrect
Vendor Specification
2/14/2023
CR-2024-00078
Startup Transformer Bushings are Beyond the Normal Life
Expectancy of 30 Years
01/04/2024
CR-2024-00153
Transfer of CWMT #1 to CWMT #2 during RE1770 A/B
Testing (ACE)
01/08/2024
CR-2024-00232
Individual Accessed Radiological Control Area (RCA) without
a Thermoluminescent Dosimeter (TLD)
01/10/2024
CR-2024-00407
Adverse Trend in Human Performance Events and errors
Since November 2023 at Davis-Besse
01/16/2024
CR-2024-00824
Security Did Not Meet 1 of 2 Objectives from the Area of
Concern
2/01/2024
CR-2024-01034
MS-C-24-02-22: No Condition Report for a 10CFR21
Notification from Velan
2/08/2024
CR-2024-01052
MS-C-24-02-22: Corrective Action Response Does Not
Include Sufficient Objective Evidence for Closure as
Required by CAP
2/09/2024
CR-2024-01054
MS-C-24-02-22: Effectiveness Review ER-2023-01268-1 Is
Not Correct
2/09/2024
CR-2024-01119
Increase in Human Performance Errors Within Security
2/13/2024
CR-2024-01181
MS-C-24-02-09: PMT Leak Check Hold Time Information Not
Properly Documented and Missing Painter Initial
2/15/2024
CR-2024-01182
MS-C-24-02-09: Issues with Order 200867885
Documentation
2/15/2024
CR-2024-01340
Aggregate Review of Ground Settling/Buried Piping Leaks at
Davis-Besse
2/21/2024
CR-2024-01446
Radioactive Material Identified during Baseline Survey.
2/23/2024
CR-2024-01529
CFAM Elevation Notice - Davis-Besse Site Protection
Inconsistent Application of Security Fundamentals
2/27/2024
Corrective Action
Documents
CR-2024-02076
Unexpected Dose Rates Found during Incore Tank Survey
03/12/2024
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
CR-2024-02170
NRC Identified - Improvement Opportunity with Alpha
Monitoring
03/14/2024
CR-2024-02249
Water Accumulation in Fire Pump Diesel Day Tank
03/16/2024
CR-2024-02254
RCP 1-2 Whip Restraint SE Nuts Loose
03/16/2024
CR-2024-02338
Positive Whole Body Count on Steam Generator Worker
03/19/2024
CR-2024-02488
Integrated SFAS Test Train 1 Required Evaluation of IST
Program Document for Valve Stroke Times - 1R23
03/22/2024
CR-2024-02599
MS Line 2 to AFPT 1 Isolation Valve MS106A Tripping
Closed with SG Pressure >20PSIG
03/26/2024
CR-2024-02942
Calculated RCS Flowrate per DB-SP-03358 Exceeds Core
Tilt Limit
04/04/2024
CR-2024-03162
Fire Piping Rupture Outside the Turbine Building Near the
Tool Crib Entrance
04/11/2024
CR-2024-03180
Station Blackout Diesel Fuel Oil Day Tank Elevated
Micro-Organism
04/12/2024
CR-2024-03400
Trending: Spent Fuel Pool Leakage/SF99-Q, ZONE 2 FUEL
TRANSFER PIT FLOOR LEAK MONITOR DRAIN, Blockage
Impacts
04/18/2024
CR-2024-03413
EPZ Siren 002 Located in Jerusalem Township in Lucas
County Failed the April 17, 2024, Siren Test.
04/18/2024
CR-2024-03734
Irregular Thermoluminescent Dosimeter (TLD) Results From
2nd Half 2023
04/26/2024
CR-2024-04083
Individual Alarms Passive Monitor Upon Issuance of Dose of
Legal Record Dosimeter
05/06/2024
CR-2024-04337
Trending Small Changes in CTRM Indications Following
CTRM Ventilation Swap.
05/14/2024
CR-2024-04787
Main Steam Line Room 1 (Room 601) Temperature
Exceeded 120 Degrees Fahrenheit
05/30/2024
CR-2024-04911
RCS Leakage Trends Not in MAOM at Time of Publishing
06/04/2024
CR-2024-05061
Level 4 Clearance Discrepancy
06/11/2024
CR-2024-05271
Surveillance Testing to Fulfill SR 3.3.1.3 Not Performed on a
Staggered Test Basis
06/20/2024
CR-2024-05297
MS-C-24-05-31: Staged Combustibles Not Addressed in Fire
Loading Calculations
06/20/2024
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
CR-2024-05444
Turbine Building North Slab Trending
06/26/2024
CR-2024-05571
Level 4 Clearance Condition
07/02/2024
CR-2024-05576
Level 4 Clearance Issue for C49 Work
07/02/2024
CR-2024-06093
RCP 1-2 Nuclear Safety Concern
07/25/2024
CR-2024-06186
Discrepancy Between Plant Drawing and Field Wiring
07/30/2024
CR-2024-06323
Level 4 Clearance Issue
08/05/2024
CR-2024-06451
NRC Identified (NRC Inspection 71130.05): CR-2021-05955-
ATA-01 Closed without Supporting Justification.
08/08/2024
CR-2024-06580
EP Drill: 8/13/24: Drill Participant Did Not Respond
08/14/2024
CR-2024-06768
Concern Identified Regarding Concurrent Yellow Risk
Surveillance Testing
08/22/2024
CR-2024-06827
Demin Water Transfer Pump 1 Trip Due to Mispositioning of
Switch
08/26/2024
CR-2024-06857
NRC Identified Fire Barrier Question
08/27/2024
CR-2024-06873
NRC Identified Fire Barrier Penetration Question
08/27/2024
CR-2024-06932
Level 4 Clearance Event - Potential Drawing Discrepancy on
E-666 Sh1
08/29/2024
CR-2024-07102
Preliminary Indications Identified Potential Rotation Issues
with Siren 504 Following Testing.
09/06/2024
CR-2024-07221
NRC Identified Concern (Protected Equipment Postings)
09/11/2024
CR-2024-07227
EPZ Siren 005 Did Not Receive the Test Signal during the
Silent Siren Test on 09/11/2024
09/11/2024
CR-2024-07386
INPO Temporary Modifications (>1 Cycle) Indicator Yellow
for August 2024
09/18/2024
CR-2024-07412
Fleet Assessment Notice of Concern - Negative Trend in
Plant Status Control, Bumping of Components
09/19/2024
CR-2024-07435
License Event Report (LER) 2021-001 Revision 01
09/19/2024
CR-2024-07563
Security Did Not Meet 1 Objective from the Area of Concern
09/25/2024
CR-2024-07800
10/04/2024
CR-2024-07935
EDG Speed Switch Evaluation Concludes an Unanalyzed
Condition Existed.
10/10/2024
CR-2024-08176
Siren 205 in Ottawa County Had a Communications Failure
during 10/18/2024 Testing.
10/18/2024
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
CR-2024-08416
Plant Status Control Event - SW37, CCW HEAT
EXCHANGER 3 OUTLET ISOLATION, Inadvertently Left
Closed During Performance of DB1OP-06262, Attachment
(ACE)
10/26/2024
CR-2024-08554
Several Telephone Lines Were Found Dead During
Walkdown/Communication Test at the Joint Information
Center Emergency Response Facility
10/31/2024
CR-2024-09019
NRC NCV: Inadequate Assessment of Fire Brigade
Performance (ACE)
11/18/2024
CR-2024-09020
NRC NCV: Reactor Protection System Flow Modules Found
Not Conforming to Design
11/18/2024
CR-2024-09356
Meteorological Tower Primary 75M Wind Speed Failed
2/04/2024
CR-2024-09424
Davis-Besse Backup 4-Way Blast Dial Server is Out of
Service
2/09/2024
CR-2024-09449
Error in Historical CCW HX 1 Performance Test
2/10/2024
CR-2024-09582
NRC NCV: Failure to Ensure Adequate Auxiliary Feedwater
Pump Minimum Flow
2/16/2024
CR-2024-09751
Primary 75-Meter Wind Direction Indicating Erratically.
2/25/2024
CR-2025-00041
Siren 103 Current Fail After 1/3/25 Audible Test
01/03/2025
CR-2025-00151
Outside Phones Lines are Out of Service
01/09/2025
CR-2025-00155
75M Wind Direction Drift from Acceptable Direction
01/09/2025
CR-2025-00727
During testing, Lucas County Emergency Operations Center
Could Not be Contacted From the Emergency Operations
Facility 4-Way Phone
2/04/2025
CR-2025-00888
Annunciator 6-1-B Failed to Flash during Annunciator Panel
Testing
2/10/2025
CR-2025-00917
Unsatisfactory Simulator DEP Classification
2/11/2025
CR-2025-00934
Davis-Besse 2024 Safety Conscious Work Environment
Survey Chemistry Red Pillars
2/12/2025
CR-2025-00936
Davis-Besse 2024 Safety Conscious Work Environment
Survey Security Red Pillar
2/12/2025
CR-2025-00939
IIS: As-Found Condition of T86-4 and DA1144 Penetration
2/12/2025
CR-2025-00992
EDG Air Start Tank T86-4 Relief Concern
2/13/2025
Corrective Action
Documents
CR-2025-01139
Draft Tornado dP Calculation Results
2/20/2025
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
CR-2025-01226
Davis-Besse 2024 Safety Conscious Work Environment
Survey Other Site Matrixed Organization Red Pillar
2/25/2025
CR-2025-01263
EDG Air Receiver Tank Returned to Service with Identified
Condition from Internal Tank Inspection Not Fully Understood
2/26/2025
CR-2025-01586
P465 and Q479 Received during Valve Stroke of HP2A
03/08/2025
CR-2025-02078
Site Protection Did Not Meet the Effectiveness Review
Criteria Listed in ER-2024-01119-1
03/24/2025
CR-2025-02356
Improvement Opportunity - CREVS Testing
04/01/2025
CR-2025-02751
Received Computer Points Q479 HP INJ VLV LEAKING and
04/13/2025
CR-2025-03150
25 NRC PI&R Inspection: Backup Call Manager is Out of
Service
04/24/2025
CR-2025-03358
25 NRC PI&R Inspection - Trend - Radiation Protection
Decrease in Condition Report Initiation
05/01/2025
Corrective Action
Documents
Resulting from
Inspection
CR-2025-03602
25 NRC PI&R Inspection: Observation on CR
Documentation
05/12/2025
24-1158-001
TM - AFW Pump Recirculation Rupture Disk
Engineering
Changes
CR-2014-08079
Leakage Indicated on HP57/HP59 and HP56/HP58 Back to
Back Check Valve Test, DB-PF-03969
05/01/2014
Surveillance Test Intervals (STI) List
ATL-2025-0147
24 SCWE Survey: Davis-Besse - Negative Red Questions
and Department/Section Discussions
2/11/2025
OE-2021-0105-6
NRC Information Notice 2020-04: Operating Experience
Related to Failure of Buried Fire Protection Main Yard Piping
04/20/2023
OE-2023-0138-1
OE547830R20230412 Turbine Trip due to Primary Phase
Differential Generator Lockout
05/10/2023
OE-2023-0341-1
IER L1-17-5, Rev.1 Line of Sight to the Reactor Core
08/22/2023
OE-2023-0397-1
OE559877R20230914 Main Generator Transformer Lockout
Caused By Failed Lightning Arrestor
01/04/2024
OE-2023-0482-1
OE563910R20231103 Degraded Service Water Piping
01/03/2024
Miscellaneous
OE-2023-0514-1
IN 2023-06, Emergency Telecommunication Services
Changes, ML23289A249
2/11/2023
Miscellaneous
OE-2024-0002-2
NRC Information Notice 2023-04: Operating Experience
Related to Fire Events at Decommissioning Nuclear Power
01/02/2024
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Plants In The United States
OE-2024-0012-2
Information Notice 2021-01, Supplement 1: Lessons Learned
From U.S. Nuclear Regulatory Commission Inspections of
Design-Basis Capability Of Power-Operated Valves at
Nuclear Power Plants
01/12/2024
OE-2024-0016-1
OE577016R20240114 Loss of Offsite Power Path due to
Cable Pothead Fault to Ground
03/19/2024
OE-2024-0062-1
NRC Information Notice 2024-01: Minimization And Control
of Contamination Involving Discrete Radioactive Particles
at Decommissioning Facilities
2/15/2024
OE-2024-0121-1
NRC Information Notice 2024-02: Impact on Licensee
Emergency Plans From Changes Made by Offsite Response
Organizations to Alert And Notification Systems
04/04/2024
OE-2024-0141-2
OE558315R20240415 Fuel Assembly Misplaced
10/14/2024
OE-2024-0305-1
OE587467R20240830 Main Transformer Fire Resulted in
Loss of One Train of Offsite Power and Reactor Trip
10/22/2024
OE-2024-0341-1
OE581674R20240930 Automatic Plant Runback due to
Integrated Control System
10/14/2024
DB-CH-06900
Operational Chemical Control Limits
DB-OP-06513
Auxiliary Building Non-Radioactive Areas Ventilation
DBRM-EMER-
5003
Equipment Important To Emergency Response
FLT-PI-BP1350
Corrective Action Review Board
NOBP-LP-2003
Employee Concern Program
NOBP-OP-0012
Operator Workarounds, Burdens, Control Room Deficiencies
and Operations Aggregate Assessment
NOP-LP-2001
Corrective Action Program
NOP-LP-2023
Conduct of Quality Assurance Compliance Auditing
NOP-OP-1009
Operability Determinations and Functionality Assessments
Procedures
NORM-OP-1009
SRO Review of Condition Reports
ATA-2023-10840
Review and Assess Area Radiation Monitor OE
06/29/2023
ATA-2023-11519
Operations Assessment of Procedural Workarounds in OPS
Procedures
07/11/2023
Self-Assessments
ATA-2023-20106
Emergency Diesel Generator 2 October 2023 Maintenance
11/27/2023
Inspection
Procedure
Type
Designation
Description or Title
Revision or
Date
Outage Critique
ATA-2023-21847
Davis-Besse Radiation Protection Program Review for 2024
in accordance with NOP-OP-4001 (Radiation Protection
Program)
2/28/2023
ATA-2023-2758
Conduct Rollup Assessment of Department Response to IPA
Gap and Focus Areas Following Training Cycle 23-02
2/09/2023
ATA-2023-2857
NRC Cyber Security Inspection IP71130.10 Self-Assessment
2/13/2023
ATA-2023-2857
NRC Cyber Security Inspection IP71130.10 Self-Assessment
2/13/2023
ATA-2023-4223
PM Feedback Self-Assessment
03/08/2023
ATA-2023-4498
Davis-Besse Emergency Feedwater System Assessment
03/10/2023
ATA-2023-9469
NI Divergences: Trend and Summarize Nuclear
Instrumentation Power Range Divergences
06/07/2023
ATA-2024-1977-
ATA-37
Area 8 Fitness-for-Duty Reviews/Assessments
01/26/2024
ATL-2022-0550-
ATA-16
2nd Quarter 2023 Unannounced Call-in Drill
08/25/2023
ATL-2022-0902-
ATA-05
Assess Actions Taken to Date Regarding Chemistry
Section's Three Red Pillars in the 2022 SCWE Survey
2/12/2022
ATL-2023-0258-
ATA-09
Review Project Schedules Generated to Ensure They Have
Sufficient Granularity
06/26/2024
ATL-2023-0673-
ATA-18
Monitor Quality of Completed CAP Products
01/13/2025
ATL-2024-0448-
ATA-06
Quarterly Unannounced Augmentation Drill - 3rd Quarter
24
10/10/2024
ATL-2025-0221-
ATA-05
25 NRC PI&R Inspection Document Request -
Performance Improvement
04/04/2025
QFO-2023-0008
Fitness-For-Duty Audit
10/30/2023
QFO-2024-0004
Corrective Action Program (CAP) Limited Scope Audit
2/20/2024
QFO-2024-0013
MS-C-24-08-03 Radiation Protection (QA Audit)
08/05/2024
RCS Flow Rate Test
04/04/2024
Work Orders
Troubleshoot / Repair / Replace RPS2RC2406
11/30/2023