ML26034C134
| ML26034C134 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley, Davis Besse, Perry, Comanche Peak (DPR-066, NPF-073, NPF-087, NPF-089, NPF-003, NPF-058) |
| Issue date: | 02/05/2026 |
| From: | Robert Kuntz NRC/NRR/DORL/LPL3 |
| To: | Peters K Vistra Operations Company |
| Kuntz R, NRR/DORL/LPL3 | |
| References | |
| EPID L-2025-LLA-0105 | |
| Download: ML26034C134 (0) | |
Text
February 5, 2026 Mr. Ken Peters Executive Vice President and Chief Nuclear Officer Vistra Operations Company LLC 6322 N FM 56 P.O. Box 1002 Glen Rose, TX 76043
SUBJECT:
BEAVER VALLEY POWER STATION, UNIT NOS. 1 AND 2; COMANCHE PEAK NUCLEAR POWER PLANT, UNIT NOS. 1 AND 2; DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO. 1; AND PERRY NUCLEAR POWER PLANT, UNIT NO. 1 - REGULATORY AUDIT REPORT REGARDING LICENSE AMENDMENT REQUEST RELATED TO ONLINE MONITORING PROGRAM (EPID L-2025-LLA-0105)
Dear Mr. Peters:
By letter dated July 10, 2025, Vistra Operations Company LLC, (Vistra, the licensee) submitted a license amendment request to revise the technical specifications (TSs) for Beaver Valley Power Station, Unit Nos. 1 and 2 (BVPS); Comanche Peak Nuclear Power Plant, Unit Nos. 1 and 2 (CPNPP); Davis-Besse Nuclear Power Station, Unit No. 1 (DBNPS); and Perry Nuclear Power Plant, Unit No. 1 (PNPP).
The proposed changes would revise the Definitions TS section and add a new Online Monitoring Program to the Administrative Controls TS section. Vistra proposes to use online monitoring (OLM) methodology as the technical bases to switch from time-based surveillance frequency for channel calibrations to a condition-based calibration frequency based on OLM results.
The U.S. Nuclear Regulatory Commissions (NRCs) Office of Nuclear Reactor Regulation staff conducted an audit of the information related to support its review of the amendment request.
The audit plan is available in Agencywide Documents Access and Management System (ADAM Accession No. ML25258A022.
The audit was conducted virtually through conference calls and the use of an online portal. The NRC staff held a virtual meeting on January 12, 2026, with the licensee to discuss the license amendment request and the analysis to support the request.
The purpose of the audit was to gain understanding, to verify information, and to identify information that will require docketing to support the proposed licensing action. The enclosure to this letter provides a report of the NRC staffs audit.
K. Peters If you have any questions, please contact me by telephone at (301) 415-3733 or by email at Robert.Kuntz@nrc.gov.
Sincerely,
/RA/
Robert Kuntz, Senior Project Manager Plant Licensing Branch III Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-334, 50-412, 50-445, 50-446, 50-346, and 50-440
Enclosure:
Audit Report cc: Listserv
Enclosure REGULATORY AUDIT REPORT TO SUPPORT THE REVIEW OF LICENSE AMENDMENT REQUEST TO REVISE TECHNICAL SPECIFICATIONS TO USE ONLINE MONITORING VISTRA OPERATIONS COMPANY LLC.
BEAVER VALLEY POWER STATION, UNIT NOS. 1 AND 2 DOCKET NOS. 50-334 AND 50-412 COMANCHE PEAK NUCLEAR POWER PLANT, UNIT NOS. 1 AND 2 DOCKET NOS. 50-445 AND 50-446 DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO. 1 DOCKET NO. 50-346 PERRY NUCLEAR POWER PLANT, UNIT NO. 1 DOCKET NO. 50-440
1.0 BACKGROUND
A regulatory audit is a planned license or regulation-related activity that includes the examination and evaluation of docketed and non-docketed information. The audit was conducted with the intent to gain understanding, to verify information, and to identify information that will require docketing to support the basis of a licensing or regulatory decision.
By letter dated July 10, 2025 (Agencywide Documents Access and Management System Accession No. ML25191A246), Vistra Operations Company LLC, (Vistra, the licensee) submitted a license amendment request to revise the technical specifications (TSs) for Beaver Valley Power Station, Unit Nos. 1 and 2 (BVPS); Comanche Peak Nuclear Power Plant, Unit Nos. 1 and 2 (CPNPP); Davis-Besse Nuclear Power Station, Unit No. 1 (DBNPS); and Perry Nuclear Power Plant, Unit No. 1 (PNPP).
The proposed changes would revise the Definitions technical specification (TS) section and add a new Online Monitoring Program to the Administrative Controls TS section.
Vistra proposes to use online monitoring (OLM) methodology as the technical bases to switch from time-based surveillance frequency for channel calibrations to a condition-based calibration frequency based on OLM results. Vistra stated that the proposed change is based on the U.S. Nuclear Regulatory Commission (NRC)-approved topical report (TR) AMS-TR-0720R2-A, Online Methodology Technology to Extend Calibration Intervals for Nuclear Plant Pressure Transmitters (ML21235A493).
As the NRC staff performed its review of the LAR, it was determined that a regulatory audit would assist in the timely completion of the review. The regulatory audit was performed consistent with NRC Office of Nuclear Reactor Regulation Office Instruction LIC-111, Revision 1, Regulatory Audits, dated October 31, 2019 (ML19226A274).
2.0 AUDIT ACTIVITIES AND OBSERVATIONS The remote audit was conducted using the Curtiss-Wright portal. as well as a virtual meeting with Vistra on January 12, 2026. An audit plan was provided to Vistra on September 16, 2025 (ML25258A022). The audit plan stated that the audit would run through October 17, 2025; however, due to the government shutdown, the audit concluded on January 26, 2026. The list of information uploaded by Vistra in response to interactions with the NRC staff and examined by the audit team is provided in section 4.0 below.
Vistra and Analysis and Measurement Services Corporation (AMS) staff supported the audit by providing remote access via the Curtiss-Wright portal, an internet-based electronic reading room, to requested reports and by making appropriate staff with detailed knowledge of AMS-TR-0720R1 available for discussions with the NRC staff.
Vistra provided the following information during the audit:
Provided clarification on document DVB2404R0 OLM Analysis Methods and Limits Report for Davis-Besse regarding tables referenced in these questions, in addition to going over the calculations used to populate the information of the associated report.
Clarified how various transmitters listed in the document DVB2404R0 OLM Analysis Methods and Limits Report for Davis-Besse are being incorporated into the proposed OLM program.
Provided clarification and updates to document PER2402R0, OLM Analysis Methods and Limits Report for Perry over the calculations used to populate criteria following AMS Topical Report AMS-TR-0720R2-A, for the information of the associated report.
Provided discussion points to NRC staff for document DVB2403R0 OLM Amenable Transmitters Report for Davis-Besse which led to updates to the associated report.
Notes for each of the AMS documents audited, as listed in section 4 of this summary report, are provided below:
OLM Amenable Transmitters Report, (documents 1 - 4; BVR2405R0, COP2402R0, DVB2403R0, PER2401R0).
These reports address steps 1 through 6 of section 11.1.1 of the TR for the transmitters in each of the Nuclear Plants that are included in the OLM program. It identifies groups of pressure, level and flow transmitters for each unit that qualify to be entered into the OLM programs.
OLM Analysis Methods and Limits Report (documents 5 - 8; BVR2406R0, COP2403R0, DVB2404R0, PER2402R0).
This report addresses steps 7 through 8 of section 11.1.1 of the TR AMS-TR-0720R2-A for the Vistra plant transmitters being proposed in this license amendment request for the OLM program.
Procedure for Performing Dynamic Failure Mode Assessment Using Noise Analysis (document 9; NPS2201R1).
This procedure provides general guidelines for performing dynamic failure mode assessment using the noise analysis method.
Procedure for Noise Data Collection from Plant Sensors (document 10; NPS1501R0).
This procedure provides guidelines for the collection of noise data to determine the dynamic performance characteristics of sensors and systems in nuclear power plants and other processes. This procedure is used for on-line data acquisition from a wide variety of sensors and systems while the plant is operating at any mode that provides adequate signal amplitudes for analysis.
OLM Noise Analysis Program Report (documents 11 - 14; BVR2408R0, COP2405R0, DVB2406R0, PER2404R0).
These reports provide the steps that must be followed to implement noise analysis for assessment of transmitter dynamic failure modes. The steps described are to be repeated at each operating cycle at BVPS, CPNPP, DBNPS and PNPP for a minimum of one transmitter on a staggered basis in each redundant group which has a response time requirement as outlined to identify its dynamic failure modes. The steps outlined in this document ensure that proper noise analysis equipment is used, and data is properly acquired, qualified, analyzed, interpreted, reported, and documented.
Procedure for Performing Online Monitoring Data Qualification and Analysis, (document 15; OLM2202R1).
This procedure outlines the general steps that are followed when performing OLM data analysis of the data being retrieved. It provides general steps that are followed when analyzing OLM data, not specific to Entergy.
Procedure for Online Monitoring Data Retrieval (document 16; OLM2201R0).
This test procedure is for retrieving OLM data from the plant historian using the AMS Bridge software. It provides general steps that are followed when retrieving OLM data, not specific to Entergy plants being proposed.
OLM Drift Monitoring Program Report (documents 17 - 20; BVR2407R0, COP2404R0, DVB2405R0, PER2401R0).
These documents provide the steps to be followed to implement OLM for transmitter drift monitoring in accordance with TR AMS-TR-0720R2-A for the plants being proposed for OLM. The steps described in the document are intended to be repeated at each operating cycle to identify the transmitters that should be scheduled for a calibration check.
Following the steps in this document will ensure that OLM data is properly acquired, qualified, analyzed, interpreted, reported, and documented.
3.0 AUDIT TEAM The following NRC staff members participated in the audit:
- Robert Kuntz, Senior Project Manager
- Gilberto Blas, Electronics Engineer
- Frederick OBrien, Electronics Engineer 4.0 DOCUMENTS PROVIDED IN ELECTRONIC READING ROOM The following documents were provided by Vistra for NRC staff review during the audit:
- 1.
BVR2405R0, OLM Amenable Transmitters Report for Beaver Valley Units 1 and 2
- 2.
COP2402R0, OLM Amenable Transmitters Report for Comanche Peak Units 1 and 2
- 3.
DVB2403R0, OLM Amenable Transmitters Report for Davis Besse Unit 1
- 4.
PER2401R0, OLM Amenable Transmitters Report for Perry Nuclear Power Plant
- 5.
BVR2406R0, OLM Analysis Methods and Limits Report for Beaver Valley Units 1 and 2
- 6.
COP2403R0, OLM Analysis Methods and Limits Report for Comanche Peak Units 1 and 2
- 7.
DVB2404R0, OLM Analysis Methods and Limits Report for Davis Besse Unit 1
- 8.
PER2402R0, OLM Analysis Methods and Limits Report for Perry Nuclear Power Plant
- 9.
NAR2201R1, Procedure for Performing Dynamic Failure Mode Assessment Using Noise Analysis
- 10. NPS1501R0, Procedure for Noise Data Collection from Plant Sensors
- 11. BVR2408R0, OLM Noise Analysis Program Report for Beaver Valley Units 1 and 2
- 12. COP2405R0, OLM Noise Analysis Program Report for Comanche Peak Units 1 and 2
- 13. DVB2406R0, OLM Noise Analysis Program Report for Davis Besse Unit 1
- 14. PER2404R0, OLM Noise Analysis Program Report for Perry Nuclear Power Plant
- 15. OLM2202R1, Procedure for Performing Online Monitoring Data Qualification and Analysis
- 16. OLM2201R0, Procedure for Online Monitoring Data Retrieval
- 17. BVR2407R0, OLM Drift Monitoring Program Report for Beaver Valley Units 1 and 2
- 18. COP2404R0, OLM Drift Monitoring Program Report for Comanche Peak Units 1 and 2
- 19. DVB2405R0, OLM Drift Monitoring Program Report for Davis Besse Unit 1
- 20. PER2403R0, OLM Drift Monitoring Program Report for Perry Nuclear Power Plant
- 21. AMS Report No. VIS2501R0, AMS Response to Audit Questions for Davis-Besse and Perry Nuclear Plants License Amendment Request to Use Online Monitoring Methodology EPID: L-2025-LLA-0105
- 22. AMS Report No. VIS2601R0, AMS Response to Audit Question for Davis-Besse Nuclear Plant License Amendment Request to Use Online Monitoring Methodology EPID: L-2025-LLA-1015 5.0 AUDIT CONCLUSION There were no regulatory decisions made during the audit. There were no open items needing further clarification. Based on the audit activities, the NRC staff determined no additional information is needed on the docket, and the staff can complete its review.
There was one deviation from the audit plan, the audit was extended from October 27, 2025, to January 26, 2026.
ML26034C134 NRR-106 OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA NRR/DEX/EICB/BC (A)
NAME RKuntz SLent SDarbali DATE 2/3/26 2/3/26 1/28/26 OFFICE NRR/DORL/LPL3/BC (A)
NRR/DORL/LPL3/PM NAME IBerrios RKuntz DATE 2/4/26 2/5/26