IR 05000327/2025010

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Notification of Sequoyah, Units 1 and 2 - Comprehensive Engineering Team Inspection - U.S. Nuclear Regulatory Commission Inspection Report 05000327/2025010 and 05000328/2025010
ML24303A150
Person / Time
Site: Sequoyah  Tennessee Valley Authority icon.png
Issue date: 10/29/2024
From: Masters A
NRC/RGN-II/DORS
To: Jim Barstow
Tennessee Valley Authority
References
IR 2025010
Download: ML24303A150 (1)


Text

SUBJECT:

NOTIFICATION OF SEQUOYAH, UNITS 1 AND 2 - COMPREHENSIVE ENGINEERING TEAM INSPECTION - U.S. NUCLEAR REGULATORY COMMISSION INSPECTION REPORT 05000327, 328/2025010

Dear Jim Barstow:

The purpose of this letter is to notify you that the U.S. Nuclear Regulatory Commission (NRC)

Region II staff will conduct a Comprehensive Engineering Team Inspection (CETI) at your Sequoyah, Units 1 and 2 during the weeks of January 27 and February 10, 2025. Mr. Adam Ruh, a Senior Reactor Inspector from the NRCs Region II office, will lead the inspection team.

The inspection will be conducted in accordance with Inspection Procedure 71111.21M, Comprehensive Engineering Team Inspection (CETI), issued October 7, 2022.

The inspection will evaluate the capability of components that have been modified and risk-significant/low-margin components to function as designed and to support proper system operation. The inspection will also include a review of selected operator actions, and operating experience, and modifications.

During a phone conversation on October 24th, 2024, with Mr. Scott Bowman, we confirmed arrangements for an information-gathering site visit and the two-week onsite inspection. The schedule is as follows:

Information-gathering visit: Week of November 11, 2024

Onsite weeks: Weeks of January 27 and February 10, 2025 The purpose of the information-gathering visit is to meet with members of your staff to identify components that have been modified, risk-significant components, and operator actions.

Information and documentation needed to support the inspection will also be identified.

Mr. Shane Sandal, a Region II Senior Reactor Analyst, will support Mr. Ruh during the information-gathering visit to review probabilistic risk assessment data and identify components to be examined during the inspection. Additionally, during the onsite weeks, time may be needed on the plant-referenced simulator to facilitate the development of operator action-based scenarios.

The enclosure lists documents that are requested to support sample selection following the information-gathering visit. Please provide the referenced information by Wednesday, November 20, 2024. Additional documents will be requested following the information-gathering October 29, 2024 visit. The inspectors will try to minimize your administrative burden by specifically identifying only those documents required for inspection preparation. The additional information will be needed in the Region II office by Wednesday, January 15, 2025, to support the inspection teams preparation week. During the information-gathering trip, Mr. Ruh will also discuss the following inspection support administrative details: (1) availability of knowledgeable plant engineering and licensing personnel to serve as points of contact during the inspection; (2)

method of tracking inspector requests during the inspection; (3) licensee computer access; (4)

working space; (5) arrangements for site access; and (6) other applicable information.

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 10 CFR 2.390, Public Inspections, Exemptions, Requests for Withholding.

Thank you for your cooperation in this matter. If you have any questions, regarding the information requested or the inspection, please contact Mr. Ruh at 404-997-4669 or contact me at 404-997-4710.

Sincerely, Anthony Masters, Chief Engineering Branch 1 Division of Operating Reactor Safety Docket Nos. 05000327 and 05000328 License Nos. DPR-77 and DPR-79 Enclosure:

Information Request for Sequoyah, Units 1 and 2 Comprehensive Engineering Team Inspection cc w/ encl: Distribution via LISTSERV Signed by Masters, Anthony on 10/29/24

ML24303A150 X

SUNSI Review X

Non-Sensitive

Sensitive X

Publicly Available

Non-Publicly Available OFFICE R2/DRS/EB1 R2/DORS/EB1 NAME A. Masters A. Ruh DATE 10/29/2024 10/29/2024

Enclosure INFORMATION REQUEST FOR SEQUOYAH, UNITS 1 AND 2 COMPREHENSIVE ENGINEERING TEAM INSPECTION Please provide the information electronically in.pdf files, Excel, or other searchable format on CDROM (or FTP site, SharePoint, etc.). The CDROM (or website) should be indexed and hyperlinked to facilitate ease of use. The requested items below, identified with an asterisk (*),

should have a date range from December 15, 2021, until present.

Information requested to support information gathering visit:

1.

  • List of modifications to systems, structures or components (SSCs) that are permanent and field work completed. (For the purpose of this inspection, modifications include permanent: plant changes, design changes, calculation changes, procedure changes, and set point changes.)

The list should contain the number of the modification, a short description, affected system and unit. If multiple categories/stages of modifications exist, provide a description of the types relative to the coding scheme in your transmittal. Additionally, the list should be categorized by quality level (i.e., safety or non-safety) as well as whether accompanied by a screening or 10 CFR 50.59 evaluation. A query report return-field-set might look like:

e.g. If systems are provided with some type of number or acronym designation, define the systems designation on a separate list or document

e.g. Engineering Design/Document Change, Design Change Notice, Test, Experiment, etc.

e.g. Closed, Returned to Operation, Void, Partially Completed, Released for Installation, Phase 1 Completed, etc.

e.g. Safety Related or Non-Safety Related

e.g. Screened Out or Full 10 CFR 50.59 Evaluation 2.

From your most recent probabilistic safety analysis (PSA) excluding external events and fires:

a.

Two risk rankings of components from your site-specific PSA: one sorted by Risk Achievement Worth (RAW), and the other sorted by Birnbaum Importance b.

A list of the top 500 cut-sets c.

A list of the top 500 LERF contributors 3.

From your most recent PSA including external events and fires:

a.

Two risk rankings of components from your site-specific PSA: one sorted by RAW, and the other sorted by Birnbaum Importance b.

A list of the top 500 cut-sets 4.

Risk ranking of operator actions from your site-specific PSA sorted by RAW and human reliability worksheets for these items 5.

List of time-critical operator actions with a brief description of each action with applicable administrative procedures used to maintain them 6.

  • List and brief description of Root Cause Evaluations performed Identifier Unit System1 Description Type2 Status3 QA Condition4 50.595

7.

8.

  • List and reason for equipment that has been classified in maintenance rule (a)(1) status and most recent (a)(3) review.

9.

  • List of equipment on the sites Station Equipment Reliability Issues or Heat Map lists, including a description of the reason(s) why each component is on that list, and summaries (if available) of your plans to address the issue(s) along with dates added or removed from the issues list 10. List of current operator work arounds/burdens and control room deficiencies 11. List of heat exchangers covered by license renewal or service water programs 12. List of motor operated valves and air operated valves in IST/valve programs and their associated design margin (i.e. High/Medium/Low), risk ranking (i.e. High/Medium/Low), and IST Program document.

13. List (procedure number, title, and current revision) of station Emergency Operating Procedures, Abnormal Operating Procedures, and Annunciator Response Procedures 14. Copies of corrective action documents generated from previous design bases assurance inspections 15. Copy of any self-assessments performed, and corrective action documents generated, in preparation for current comprehensive engineering team inspection 16. Contact information for a person to discuss PSA information prior to and during the information-gathering trip (Name, title, phone number, and e-mail address)

17. List of system acronyms 18. One-line diagram of electrical plant (Electronic only)

19. *List of components with low-design margins (i.e., pumps closest to the design limit for flow or pressure, diesel generator close to design-required output, heat exchangers close to rated design heat removal, and motor-operated valve risk-margin rankings, etc.) and associated evaluations or calculations 20. Copy of procedures addressing the following: loss of service water system or ultimate heat sink (UHS); controls to prevent clogging due to macrofouling; and performance, testing, and inspection requirements for service water system and UHS 21. Primary AC and DC calculations for safety-related buses