ML21246A053
| ML21246A053 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 09/15/2021 |
| From: | Perry Buckberg Plant Licensing Branch II |
| To: | Jim Barstow Tennessee Valley Authority |
| Buckberg P, NRR/DORL/LPL2-2 | |
| References | |
| EPID L 2021 LLA 0145 | |
| Download: ML21246A053 (10) | |
Text
September 15, 2021
Mr. James Barstow Vice President, Nuclear Regulatory Affairs and Support Services Tennessee Valley Authority 1101 Market Street, LP 4A-C Chattanooga, TN 37402-2801
SUBJECT:
SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2 - REGULATORY AUDIT IN SUPPORT OF REVIEW O F THE APPLICATION TO ADOPT RISK-INFORMED EXTENDED COMPLETION TIMES - RITSTF INITIATIVE 4 B (EPID L-2021-LLA-0145)
Dear Sir or Madam:
By letter dated August 5, 2021, (Agencywide Documents Access an d Management System (ADAMS) Accession No. ML21217A174), Tennessee Valley Authority (the licensee) submitted a license amendment request for Sequoyah Nuclear Plant, Units 1 a nd 2, respectively. The proposed amendments would modify the plants Technical Specific ation requirements to permit the use of risk-informed completion times in accordance with Te chnical Specification Task Force Traveler TSTF 505, Provide Risk-informed Extended Comple tion Times, RITSTF
[Risk-Informed Technical Specification Task Force] Initiative 4 b.
The U.S. Nuclear Regulatory Commission (NRC) staff has identifi ed the need for a regulatory audit to examine the licensees non-docketed information with t he intent to gain understanding, to verify information, or to identify information that will req uire docketing to support the basis of the licensing or regulatory decision.
The NRC staff will conduct the audit virtually at NRC Headquart ers in Rockville, Maryland, via a licensee-established electronic portal available to NRC staff f rom approximately September 20, 2021, through March 31, 2022, with formal audit meetings to be scheduled during this period as needed. The detailed audit plan is enclosed with this letter.
J.Barstow
If you have any questions, please contact me at (301) 415-1383 or by e-mail at Perry.Buckberg@nrc.gov.
Sincerely,
/RA/
Perry H. Buckberg, Senior Project Manager Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
Docket Nos. 50-327 and 50-328
Enclosure:
Audit Plan
cc: Listserv REGULATORY AUDIT PLAN
BY THE OFFICE OF NUCLEAR REACTOR REGULATION
TO SUPPORT THE REVIEW OF THE LICENSE AMENDMENT REQUEST
TO ADOPT RISK-INFORMED COMPLETION TIMES
TENNESSEE VALLEY AUTHORITY
SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2
DOCKET NOS. 50-327 AND 50-328
1.0 BACKGROUND
By letter dated August 5, 2021 (Reference 1), Tennessee Valley Authority (the licensee) submitted a license amendment request (LAR) to amend Renewed Operating License Nos. DPR-77 and DPR-79 for the Sequoyah Nuclear Plant, Units 1 and 2, respectively. The proposed amendment would modify the plants Technical Specification (TS) requirements to permit the use of risk-informed completion times (RICTs) in accordance with Technical Specification Task Force (TSTF) Traveler TSTF-505, Provide Risk-informed Extended Completion Times, RITSTF [Risk-Informed Technical Specification Tas k Force] Initiative 4b (Reference 2.). These RICTs would apply to certain actions required when limiting conditions for operation are not met.
The staff from the Nuclear Regulatory Commissions (NRC) Office of Nuclear Reactor Regulation (NRR) has initiated its review of the LAR in ac cordance with NRR Office Instruction LIC-101, License Amendment Review Procedures (Reference 3).
2.0 REGULATORY AUDIT BASIS
A regulatory audit is a planned license-or regulation-related activity that includes the examination and evaluation of primarily non-docketed information associated with the LAR. An audit is conducted to gain understanding, to verify information, and to identify information that will require docketing to support the basis of a licensing or regulatory decision. An audit will assist the NRC staff in efficiently conducting its review and gaining insights to the licensees processes and procedures. Information that the NRC staff relies upon to make the safety determination must be submitted on the docket. This audit will be conducted in accordance with NRR Office Instruction LIC-111, Regulatory Audits, Revision 1, dated October 2019 (Reference 4), with exceptions noted within this audit plan.
The NRC staff will perform the audit to support its evaluation of whether the licensees LAR can be approved per Title 10 of the Code of Federal Regulations (10 CFR), Section 50.90, Application for amendment of license, construction permit, or early site permit. The staffs review will be informed by NUREG-0800, Standard Review Plan Section 19.2, Review of Risk Information Used to Support Permanent Plant-Specific Changes to the Licensing Basis (Reference 5). The audit will assist the NRC staff with understanding the licensees proposed program to implement RICTs for certain TSs.
Enclosure
- 2 -
3.0 REGULATORY AUDIT SCOPE AND METHODOLOGY
NRCs objectives of the audit are the following:
Learn how the licensees proposed program implements TSTF-505 and conforms to NRC-endorsed guidance in Nuclear Energy Institute (NEI) report NEI 06-09, Revision 0-A, Risk-Informed Technical Specification Initiative 4b, Risk-Managed Technical Specification Guidelines (Reference 6).
Gain a better understanding of the detailed calculations, analyses, and ba ses underlying the LAR and confirm the staffs under standing of the LAR.
Gain a better understanding of plant design features and their implications for the LAR.
Identify any information needed to enable the staffs evaluati on of the technical acceptability of the probabilistic risk assessment (PRA) used f or this application.
Identify any information needed to enable the staffs evaluati on of whether the proposed changes challenge design-basis functions or adversely affect the capability or c apacity of plant equipment to perform design-basis fun ctions.
Identify questions and requests that may become formal requests for ad ditional information (RAIs) per NRR Office Instruction LI C-115, Processing Requests for Additional Information (Reference 7).
The NRC staff will audit the PRA methods that the licensee woul d use to determine the risk impact from which the revised completion times would be obtaine d, including the licensees assessments of internal events (including internal flooding), fire, and seismic probabilistic risk assessments (PRAs). The NRC will also audit the licensees assessment of risk from other external events, and the licensees evaluation of defense-in-de pth.
4.0 INFORMATION AND OTHER MATERIAL NECESSARY FOR THE AUDIT
The NRC staff will request information and an audit meeting(s) throughout the audit period. The NRC staff will use an audit items list to identify the inform ation (e.g., methodology, process information, and calculations) to be audited. The NRC staff will provide the final audit items list as an enclosure to the audit summary report, which will be publ icly available. The attachment to this audit plan includes the initial audit items list. Through out the audit period, the NRC staff will provide the licensee with audit questions and audit-related req uests so that the licensee can better prepare for audit discussions with NRC staff. Any infor mation accessed through the licensees portal will not be held or retained in any way by NR C staff. The NRC staff requests the licensee to have the requested audit information listed in the audit items list to be readily available and accessible for the NRC staffs review via a Web-based portal.
5.0 TEAM ASSIGNMENTS
The audit team will consist of the following NRC staff from NRR and contractors.
Perry Buckberg, Plant Licensing Bran ch 2-2 (LPL2-2)
Ed Miller, LPL2-1 Todd Hilsmeier, PRA Licensing Bran ch A (APLA)
Jigar Patel, APLA Thinh Dinh, PRA Licensing Branch B (APLB)
Naeem Iqbal, APLB Bernard Grenier, APLB
Milton Valentin-Olmeda, PRA Licensing Branch C (APLC)
De (Wesley) Wu, APLC Khadijah West, Technical Specifications Branch (STSB)
Hanry Wagage, Containment and Plant Systems Branch (SCPB)
Norbert Carte, Instrumentation and Controls Branch B (EICB)
Joseph Ashcraft, EICB Edmund Kleeh, Electrical Engineering Branch (EEEB)
Adakou Foli, EEEB Summer Sun, Nuclear Systems Performance Branch (SNSB)
Garill Coles, Pacific Northwest National Laboratory (PNNL)
Steve Short, PNNL
6.0 LOGISTICS
To support the review schedule communicated to Tennessee Valley Authority (TVA) when the NRC staff accepted the LAR for technical review, audit activiti es will be performed remotely and virtually using Microsoft Teams, teleconference, and a Web-base d portal or other virtual meeting space created by the licensee. NRC information request s and communications with licensee staff will be coordinated through the NRCs licensing project manager.
The virtual audit will begin approximately September 20, 2021, and will last through March 31, 2022. The NRCs entrance meeting with the licensee w ill likely be in late September 2021. The NRCs licensing project manager will inform the lice nsee of the entrance and exit meeting dates when they are established. The NRC intends to es tablish an audit meeting(s)
(e.g., a single, multi-day audit meeting; periodic audit meetin gs throughout the audit period) on mutually agreeable dates and times (to be determined) to discus s information needs and questions arising from the NRCs review of the audited items.
The NRC staff requests the licensee to have the information ref erenced in Section 4.0 of this audit plan available and accessible for the NRC staffs review via an internet-based portal within 2 weeks of the date of this audit plan. The NRC staff requests that any supplemental information requested be available and accessible for the NRC s taffs review within 1 week of the date of the NRCs notification to the licensee of the new requests. The NRCs licensing project manager will inform the licensee via routine communicat ions when the NRC staff no longer needs access to the portal. The NRC staff requests the licensee to notify the review team when an audit item is added to its portal by sending an e-mail to the review team e-mail address1 or the NRC licensing project manager.
1 SequoyahTSTF-505@usnrc.onmicrosoft.com
7.0 SPECIAL REQUESTS
The NRC requests access to requested documents and information through a Web-based portal that allows the NRC staff and contractors to access documents o ver the Internet. The following conditions associated with the online portal must be maintained while the NRC staff and contractors have access to the online portal:
The online portal will be password-protected. A separate pass word will be assigned to each member of the NRC staff and NRC contractors participating in the audit.
The online portal will prevent the NRC participants from print ing, saving, downloading, or collecting any information directly from the online portal.
Conditions of use of the online portal will be displayed on th e login screen and will require acknowledgment by each user.
Username and password and/or other Web-based portal access info rmation should be provided directly to members of the NRC staff and contractors as needed. The NRC licensing project manager will provide the licensee with names and contact inform ation of the NRC staff and contractors participating in the audit. All other communicatio ns should be coordinated through the NRC project manager.
8.0 DELIVERABLES
The NRC staff will develop any RAIs, as needed, via NRR Office Instruction LIC-115 and issue such RAIs separately from audit-related correspondence. The NR C staff will issue an audit summary report prior to completing its review of the LAR.
9.0 REFERENCES
- 1. Letter from James T. Polickoski to the U.S. Nuclear Regulato ry Commission, Sequoyah Nuclear Plant, Units 1 and 2, Renewed Facility Operating Licens e Nos. DPR-77 and DPR-79, NRC Docket Nos. 50-327 and 50-328, License Amendment Re quest to Revise Technical Specifications to Adopt Risk-Informed Completion Time s TSTF-505, Revision 2, Provide Risk-Informed Extended Completion Times - RITSTF Initi ative 4b (SQN-TS 03), August 5, 2021 (Agencywide Documents Access and Managemen t System (ADAMS)
Accession No. ML21217A174).
- 2. TSTF-505, Revision 2, TSTF Comments on Draft Safety Evaluat ion for Traveler TSTF-505, Provide Risk-Informed Extended Completion Times, and Submitta l of TSTF-505, Revision 2, July 2, 2018 (ADAMS Accession No. ML18183A493).
- 3. U.S. Nuclear Regulatory Commi ssion, NRR Office Instruction LIC-101, Revision 6, License Amendment Review Procedures, July 31, 2020 (ADAMS Accession No. ML19248C539).
- 4. U.S. Nuclear Regulatory Commi ssion, NRR Office Instruction LIC-111, Revision 1, Regulatory Audits, October 31, 2019 (ADAMS Accession No. ML19 226A274).
- 5. U.S. Nuclear Regulatory Commission, NUREG-0800, Standard Re view Plan, Section 19.2, Review of Risk Information Used to Support Permanent Plant-Spe cific Changes to the Licensing Basis: General Guidance, June 2007 (ADAMS Accession No. ML071700658).
- 6. Nuclear Energy Institute, NEI 06-09, Revision 0-A, Risk-Inf ormed Technical Specification Initiative 4b, Risk-Managed Technical Specification Guidelines, November 2006 (ADAMS Accession No. ML12286A322).
- 7. U.S. Nuclear Regulatory Commi ssion, NRR Office Instruction LIC-115, Revision 1, Processing Requests for Additional Information, August 9, 202 1 (ADAMS Accession No. ML21141A238).
Initial Audit Items List
Item # Audit Item 1 Reports of full-scope and focused-scope peer reviews, facts a nd observations (F&Os) closure reviews, and any self-assessments referred to in license amendment request (LAR) Enclosure 2 for the internal events, in ternal flooding, fire, and seismic probabilistic risk assessments (PRAs) cited i n the LAR
2 For the internal events, internal flooding, fire, and seismic PRAs, plant-specific documentation (e.g., uncertainty notebooks) related to:
- a. The review of the PRA model assumptions and sources of uncer tainty (generic and plant-specific assumptions/uncertainties)
- b. Identification of key assumptions and sources of uncertainty for this LAR
- c. Parametric uncertainty and state-of-knowledge correlation ev aluation 3 PRA notebooks for the modeling of FLEX equipment and FLEX hum an error probabilities credited in the PRAs
4 PRA notebook(s) for the Reactor Protection System pertaining to modeling of the Eagle 21 digital control system, including basis for the repres entative failure probability
5 Documentation of how shared or cross-tied systems are modeled in the PRA
6 Sequoyah fire PRA notebooks containing the results of the fir e PRA
7 If available, the primary document(s) supporting the revised Sequoyah Units 1 and 2 warning time analysis to reconfirm that the external flooding hazard can be screened out using screening criterion C5 (or using the criteri a of Section 6-2-3 of ASME/ANS RA-Sa-2009 if external flooding cannot be screened as a slow-moving event).
8 If modeled, the PRA notebooks associated with the modeling of Open Phase Condition (OPC) in electrical switchyards and the Open Phase Is olation System (OPIS).
9 Documentation supporting the development of the real-time ris k tool and benchmarking it against the PRA
10 Documentation supporting the example risk informed completio n times (RICT) calculations presented in LAR Enclosure 1, Tables E1-2 and E1-3
11 Plant and PRA configuration control procedures 12 Any draft or final RICT program procedures (e.g., for risk m anagement actions, PRA functionality determination, and recording limiting conditi ons for operation) 13 Plant procedures related to risk management actions for the electrical power systems, if available 14 Relevant design documentation (e.g., single line diagrams of the electrical power distribution systems and piping and instrumentation diagrams) 15 Design details of systems shared or cross-tied between Units 1 and 2, including electrical and mechanical systems
16 Other documentation that the licensee determines to be respo nsive to the staff's information requests
Attachment
ML21246A053 OFFICE NRR/DORL/LPLII-2/PM NRR/DORL/LPLII-2/LA NRR/DRA/APLA/BC NRR/DRA/APLB/BC NAME PBuckberg RButler RPascarelli JWhitman DATE 9/9/2021 9/9/2021 9/2/2021 9/9/2021 OFFICE NRR/DRA/APLC NRR/DEX/EICB/BC NRR/DEX/EEEB/BC NRR/DSS/SNSB/BC NAME SRosenberg MWaters SRay SKrepel (RBeaton for)
DATE 9/9/2021 9/9/2021 9/9/2021 9/10/2021 OFFICE NRR/DSS/SCPB/BC NRR/DSS/STSB/BC (A) NRR/DORL/LPLII-2/PM NRR/DORL/LPLII-2/BC NAME BWittick NJordan PBuckberg DWrona DATE 9/9/2021 9/9/2021 9/15/2021 9/15/2021