ML22215A191
| ML22215A191 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 08/09/2022 |
| From: | Thomas Wengert Plant Licensing Branch IV |
| To: | Entergy Operations |
| Wengert T | |
| References | |
| EPID L-2022-LRM-0049 | |
| Download: ML22215A191 (6) | |
Text
August 9, 2022 LICENSEE:
Entergy Operations, Inc.
FACILITY:
Arkansas Nuclear One, Units 1 and 2
SUBJECT:
SUMMARY
OF JULY 13, 2022, TELECONFERENCE MEETING WITH ENTERGY OPERATIONS, INC. TO DISCUSS PLANNED LICENSE AMENDMENT REQUESTS TO ADOPT TSTF-505, PROVIDE RISK-INFORMED EXTENDED COMPLETION TIMES - RITSTF INITIATIVE 4b, AT ARKANSAS NUCLEAR ONE, UNITS 1 AND 2 (EPID L-2022-LRM-0049)
On July 13, 2022, an Observation public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of Entergy Operations, Inc. (the licensee) via teleconference. The purpose of the meeting was to discuss the licensees planned license amendment requests (LARs) to adopt Technical Specifications Task Force (TSTF) Traveler TSTF-505, Provide Risk-Informed Extended Completion Times - RITSTF [Risk-Informed TSTF] Initiative 4b, at Arkansas Nuclear One, Units 1 and 2 (ANO-1 and ANO-2).
The meeting notice and agenda, dated June 30, 2022, are available in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML22181B058. A list of attendees is provided in the enclosure.
The licensee presented information (ML22193A026) regarding its planned LARs. The licensees presentation included an overview of its planned LARs to adopt TSTF-505, the ANO-1 and ANO-2 probabilistic risk assessment (PRA) technical adequacy, PRA uncertainties/assumptions, the modeling of Diverse and Flexible Mitigation Capability (FLEX),
and external hazards, including flooding, extreme wind, and seismic considerations.
The NRC staff queried the licensee throughout the presentation and discussed the following:
The NRC staff inquired about the status of the real time risk model that will be used by operators to determine completion times and requested that a very brief description of the risk model be included in the LARs. The licensee noted that development is in progress and a demonstration will be provided during the audit that will be conducted during the detailed review phase.
The NRC staff inquired about the licensees review of the sources of uncertainty for the applications. The NRC staff requested that the LARs include descriptions of this review and a description of how these uncertainties, if any, will be dispositioned.
The NRC staff inquired about the licensees external hazards screening process for the planned TSTF-505 LARs. The licensee explained that the screening process will be comparable to that used for the licensees applications to adopt Title 10 of the Code of Federal Regulations (10 CFR) Section 50.69, Risk-informed categorization and treatment of structures, systems and components for nuclear power reactors, at ANO-1 and ANO-2, which were recently reviewed and approved by the NRC staff (ML22138A431 and ML22165A244, respectively). The licensee also explained the distinctions between the LARs (10 CFR 50.69 and TSTF-505) in the treatment of high wind risk.
The NRC staff inquired about the overall steps involved in the licensees proposed seismic penalty method and emphasized the use of plant-specific information in supporting the licensees method. The licensee explained that it will use a conservative analysis for the core damage frequency estimate and the Farley method for the seismic large early release frequency estimate.
The NRC staff suggested that the licensee provide sufficient information when developing the List of Revised Required Actions to Corresponding PRA Functions portion of its applications. Specifically, the NRC staff requested that the licensee identify design success criteria in relation to the inoperable equipment and state the minimum equipment, based on the remaining operable equipment, that would meet the systems safety function (e.g., the design success criteria for a condition with two inoperable offsite circuits may be one of two emergency diesel generators.) The NRC staff noted that this would provide sufficient information to evaluate the effects of the proposed changes on the ANO-1 and ANO-2 accident analyses. [Note: Following the meeting, the NRC staff provided the following suggested references to the licensee for consideration: table E1-1, In Scope TS/LCO
[Technical Specification/Limiting Condition for Operation] Conditions to Corresponding PRA Functions, and related questions in the Sequoyah TSTF-505 LAR (review is in progress) in the original request dated August 5, 2021 (ML21217A174), and supplemental letters dated April 28, 2022 (ML22118A496), and May 13, 2022 (ML22133A238).]
The NRC staff suggested that the licensee provide sufficient information to demonstrate that the proposed changes to the instrumentation and control (I&C) functions are consistent with the defense-in-depth principle formulated in Regulatory Guide (RG) 1.174, An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis. The NRC staff further suggested that the licensee provide not only the redundancy information, but also the diversity analysis for the functions under change during the risk-informed completion time LARs. This information is recommended to provide the NRC staff with sufficient information to evaluate the effects of the proposed changes on the ANO-1 and ANO-2 accident analyses. [Note: Following the meeting, the NRC staff provided the following suggested references to the licensee for consideration: section 2 Evaluation of Instrumentation and Control Systems and table E1-4 RPS [Reactor Protection System] Instrumentation Diversity of enclosure 1 in the Susquehanna TSTF-505 LAR (ML21098A206) (review is in progress).]
The licensee stated that it will submit separate applications for ANO-1 and ANO-2. The licensee expects to submit the LARs in the September/October 2022 timeframe and will request approval within 1 year.
Members of the public were not in attendance. No regulatory decisions or commitments were made at the meeting. Public Meeting Feedback forms were not received.
Please direct any inquiries to me at 301-415-4037, or by email at Thomas.Wengert@nrc.gov.
/RA/
Thomas J. Wengert, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-313 and 50-368
Enclosure:
List of Attendees cc: Listserv
Enclosure LIST OF ATTENDEES JULY 13, 2022, TELECONFERENCE MEETING WITH ENTERGY OPERATIONS, INC.
ARKANSAS NUCLEAR ONE, UNITS 1 AND 2 PLANNED LICENSE AMENDMENT REQUEST TO ADOPT TSTF-505, PROVIDE RISK-INFORMED EXTENDED COMPLETION TIMES - RITSTF INITIATIVE 4b U.S. Nuclear Regulatory Commission Robert Pascarelli, Chief, NRR1/DRA2/APLA3 April Pulvirenti, NRR/DRA/APLA Jigar Patel, NRR/DRA/APLA Jeff Circle, NRR/DRA/APLA Jonathan Evans, NRR/DRA/APLA Jay Robinson, NRR/DRA/APLB4 Sunwoo Park, NRR/DRA/APLC5 Anne-Marie Grady, NRR/DRA/APLC Alex Collier, NRR/DRA/APLC Brian Wittick, Chief, NRR/DSS6/SCPB7 David Nold, NRR/DSS/SCPB Khadijah West, NRR/DSS/STSB8 Andrea Russell, NRR/DSS/STSB Fred Forsaty, NRR/DSS/SNSB9 Bart Fu, NRR/DNRL10/NPHP11 John Tsao, NRR/DNRL/NVIB12 Carol Moyer, NRR/DNRL/NVIB Stewart Bailey, Chief, NRR/DEX13/EMIB14 Sheila Ray, Acting Chief, NRR/DEX/EEEB15 Adakou Foli, NRR/DEX/EEEB Ming Li, NRR/DEX/EICB16 1 Office of Nuclear Reactor Regulation 2 Division of Risk Assessment 3 Probabilistic Risk Assessment (PRA) Licensing Branch A 4 PRA Licensing Branch B 5 PRA Licensing Branch C 6 Division of Safety Systems 7 Containment and Plant Systems Branch 8 Technical Specifications Branch 9 Nuclear Systems Performance Branch 10 Division of New and Renewed Licenses 11 Piping and Head Penetrations Branch 12 Vessels and Internals Branch 13 Division of Engineering 14 Mechanical Engineering and Inservice Testing Branch 15 Electrical Engineering Branch 16 Instrumentation and Controls Branch
U.S. Nuclear Regulatory Commission (continued)
Brian Green, Team Leader, NRR/DRO17/IOLB18 Jennifer Dixon-Herrity, Chief, NRR/DORL19/LPL420 Tom Wengert, Senior Project Manager, NRR/DORL/LPL4 Fred Sanchez, Senior Project Engineer R-IV21/DORS22/PBD23 Entergy24 Riley Keele, ANO25 Regulatory Assurance Manager Michael Hall, ANO Regulatory Assurance Mark Reid, ANO Regulatory Assurance Ashton Williams, ANO PRA Jason Hall, ANO PRA Clint Alday, Entergy Fuels Analysis Manager Phil Couture, Entergy Corporate Regulatory Assurance Senior Manager Wes Johnson, Entergy Corporate PRA Supervisor Howard Mahan, Entergy Corporate Regulatory Assurance Greg Norris, Entergy Corporate Regulatory Assurance Jensen Hughes (Contractor to Entergy)
Doug Money David Passehl Joe Renner Jeff Schappaugh Leo Shanley Don Vanover 17 Division of Reactor Oversight (DRO) 18 Operator Licensing and Human Factors Branch 19 Division of Operating Reactor Licensing (DORL) 20 Plant Licensing Branch IV 21 Region 4 22 Division of Operating Reactor Safety (DORS) 23 Plant Reactor Branch D 24 Entergy Operations, Inc.
25 Arkansas Nuclear One
Meeting Summary: ML22215A191 Meeting Notice: ML22181B058 Meeting Presentation: ML22193A026
- by email OFFICE NRR/DORL/LPL4/PM*
NRR/DORL/LPL4/LA*
NRR/DRA/APLA/BC*
NAME TWengert PBlechman RPascarelli DATE 8/5/2022 8/4/2022 8/5/2022 OFFICE NRR/DRA/APLC/BC(A)*
NRR/DORL/LPL4/BC*
NRR/DORL/LPL4/PM*
NAME SVasavada JDixon-Herrity TWengert DATE 8/8/2022 8/8/2022 8/9/2022