ML22066B274
| ML22066B274 | |
| Person / Time | |
|---|---|
| Issue date: | 03/11/2022 |
| From: | Diaztorres E NRC/NRR/DRA/APOB |
| To: | Antonios Zoulis NRC/NRR/DRA/APOB |
| Diaz-Torres P | |
| References | |
| Download: ML22066B274 (7) | |
Text
March 11, 2022 MEMORANDUM TO: Antonios Zoulis, Chief PRA Oversight Branch Division of Risk Assessment Office of Nuclear Reactor Regulation Signed by Torre FROM: Edgardo Torres, Reliability and Risk Analyst on 03/11/22 PRA Oversight Branch Division of Risk Assessment Office of Nuclear Reactor Regulation
SUBJECT:
SUMMARY
OF FEBRUARY 2, 2022, PUBLIC MEETING TITTLED PROBABILISTIC RISK ASSESSMENT CONFIGURATION CONTROL WORKSHOP BETWEEN THE U.S. NUCLEAR REGULATORY COMMISSION AND INDUSTRY STAKEHOLDERS On February 2, 2022, the U.S. Nuclear Regulatory Commission (NRC) staff held a public meeting between the NRC, industry stakeholders, and other interested parties. The Comment -
Gathering type meeting was conducted virtually. The meeting notice is available in the Agencywide Documents Access and Management System (ADAMS), at Accession Number ML21334A282. The NRC and industry presentations used to facilitate discussions during the meeting are available in ADAMS at Accession Number ML22031A255. The Nuclear Energy Institute (NEI) presented their perspective on Oversight of Probabilistic Risk Assessment (PRA)
Configuration Controls. The list of meeting participants is provided as an enclosure to this document. The staff received two public meeting feedback forms related to this meeting.
During the meeting the staff discussed the safety enhancement to the reactor oversight process (ROP) baseline inspection program by incorporating a PRA Configuration Control inspection; the potential oversight gap within the ROP baseline inspection program regarding PRA Configuration Controls; and the proposed PRA Acceptability Framework to address the oversight gap. Details on each of these topics, comments and feedback received are described on the following pages. The meeting was approximately 2.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> in length.
Enclosures:
List of Meeting Attendees CONTACT: Edgardo Torres, NRR/DRA/APOB 301-415-0705
A. Zoulis Safety Enhancement to ROP baseline inspection program The NRC discussed the safety enhancement to the ROP by providing a high-level overview of the role of PRA models into the decisionmaking of risk-informed programs (i.e., 10 CFR 50.69, Risk-Informed Completion Time, Surveillance Frequency Control Program (NFPA 805), and defining the potential adverse impact to risk-informed decisionmaking of inadequate configuration controls to those programs. In addition, PRA Configuration Control requirements were discussed for each risk-informed program. The section was concluded with emphasis to the importance of PRA Configuration Control programs as PRA models continue to inform decisions in the classification of structure, system, and components (SSCs); calculation of limiting condition for operation completion times; surveillance frequency changes; fire protection program changes; and 10 CFR 50.65(a)(4) (maintenance rule). The NRC emphasized that the maintenance rule (a)(4) is not governed by the configuration controls established by (RG) 1.200 endorsed PRA consensus standard, but NUMARC 93-01 does contain plant representation guidance that can only be met with a configuration control program for (a)(4) quantitative assessments.
No questions, comments or feedback were received during this part of the workshop.
Potential Gap within ROP PRA Configuration Control Oversight baseline inspection program The NRC discussed the identified gap in baseline inspections per Inspection Manual Chapter (IMC) 2515, Appendix A, Risk-Informed Baseline Inspection Program, (Agencywide Documents Access and Management System (ADAMS) Accession Number ML18180A098) regarding the oversight of PRA Configuration Control programs. After risk-informed applications are approved, the NRC has no regulatory footprint in this area. The staff performed a detailed gap analysis of IMC 2515, Appendix A, concluding that no procedure provides an objective nor provides guidance to inspect PRA Configuration Control. The staff confirmed the current focus of IMC 2515, Appendix A, remains on the implementation of risk-informed programs. The procedures reviewed were listed and details of the analysis were provided in the back-up slides section of the presentation.
Questions and comments are summarized in the PRA Configuration Control Workshop section.
PRA Acceptability Licensing & Oversight The NRC provided an overview of the PRA Acceptability process as described in RG 1.200 Revision 3 for risk-informed applications in licensing space. The NRC provided an overview of the PRA Acceptability areas that are the focus of NRCs oversight function. In oversight, the areas of focus to maintain PRA Acceptability are technical elements and plant representation via a configuration control program.
No questions from industry or members of the public.
Proposed PRA Acceptability Framework The NRC presented the purpose and objectives of the proposed PRA Acceptability Framework for future oversight of risk-informed programs and PRA Configuration Control. The staff presented the proposed tiered approach that represents a complete level of oversight of risk-informed programs, and PRA configuration control, within the ROP. The proposed inspection guidance concept was discussed, within the following RG 1.200 PRA Configuration Control
A. Zoulis attributes and characteristics:
Questions and comments are summarized in the PRA Configuration Control Workshop section.
NEIs Industry Perspective on Oversight of PRA Configuration Control Presentation NEIs presentation covered industries perspective on oversight of PRA Configuration Control.
These included references to current procedures outside of the baseline inspection program, directing inspectors to verify PRA Configuration Controls are being implemented; suggestions for enhancements; recommendation to maintain focus on compliance; and suggested input to support inspection of risk-informed programs.
PRA Configuration Control Workshop Through the presentation, members of the public and industry representative provided questions and comments. Questions were related to understanding the oversight gap, what the focus of the proposed guidance would be; what the concern of the NRC staff is in this area; who will be performing the inspection, and the impact of this inspection in the significance determination process; configuration controls of computer codes; concerns with inspection consistency across inspectors; the intent for the PRA maintenance vs upgrade reviews; and flex credit for licensee risk-informed applications.
Industry representatives commented on Tier 3 of the inspection framework that would cover infrequent assessment of PRA Acceptability and when such an inspection would be necessary.
Staff stated that the current focus of this effort was on Tier one and Tier two of the framework and that future work would address the third tier. Furthermore, staff emphasized that the tier would be needed when significant thresholds were met that indicated a breakdown of PRA Configuration Control and a loss of confidence by the NRC to licensees risk-informed decisionmaking.
Received comments recommended limiting the number of inspections depending on whether issues are identified or not; inspect other areas because current changes are not risk-significant and deterministic approaches have not changed; the importance to recognize uncertainties in PRA models; avoid duplication of efforts and creating process to fix another process; and potentially endorse the new revision to section 1-5, PRA Configuration Control, of the ASME/ANS PRA Standard on a different schedule, potentially incorporating observations from this effort.
Staff stated that current efforts in the development of the oversight framework would benefit from licensee participation in the planned information gathering and guidance development effort which will consist of several site visits to gain a better understanding of the current PRA configuration control practices and processes currently implemented in industry. Any guidance developed would not result in additional baseline inspection hours and would consider a balance approach based on licensee implementation of risk-informed initiatives.
Closing Remarks The public was given an opportunity to provide additional comments or questions, and no one chose to do so. The NRC DRA Division Director then thanked the participants for the good discussion and re-iterated how early in this process we are, gathering information to best inform the PRA Acceptability Framework. The meeting was then closed.
ML via email NRR-106 OFFICE NRR/DRA/APOB NRR/DRA/APOB: BC*
NAME ETorres AZoulis DATE 03/11/2022 03/11/2022 LIST OF MEETING ATTENDEES Attendee Affiliation Torres, Edgardo NRC Pressley, Lundy NRC Zoulis, Antonios NRC Caponi, Louis NRC Mihalik, Andrew NRC Hughey, John NRC Whitman, Jennifer NRC Felts, Russell NRC Ginyard, Cristal Dominion Degonish, Matthew M Westinghouse Sicard, Paul Entergy Dolan, Bradley Wicker Southern Varnedoe, Jennifer Maye Duke Seiter, Jeff Rosebrook, Andy NRC Browne, Eric Vaughan Ng, Ching NRC Johnson, Wes Landale, James Constellation Energy Szwarc, Dariusz NRC Corey M Wilson Dominion Franovich, Mike NRC Burgess, Nick Olson, Ole H. Duke Carroll, Bryan C Gish, Roger D TVA Raleigh, Deann Kvamme, Greg Hope, Kyle D Boatwright, Walter J Anderson, Victoria NEI Patterson, Malcolm Kichline, Michelle NRC Mirizio, Damian Westinghouse De Rego, Christopher Duke Kindred, Gerry Wane TVA Tim Sande Cymbor, Michael Julius, Jeffrey Jeong, Beomhee Voskuil, Jeffrey Entergy Burgio, Brian
Burg, Rob Matheny, Tara Elizabeth Pascarelli, Robert NRC Littleton, Clem Thomas, Andrew LaBarge, N. Reed Mohamed M. Talaat Vasavada, Shilp NRC Enrique Melendez Asensio Treadway, Ryan I Hilsmeier, Todd NRC Lipetzky, Andrew Charles Duke Boyer, Robert P Duke Loyd, Suzanne Constellation Energy Hipschman, Thomas NRC Linthicum, Roy R Constellation Energy Maioli, Andrea Westinghouse Seyedhosseini, Shahin PSEG Reisi Fard, Mehdi NRC Arner, Frank NRC Garmoe, Alex NRC Hall, Jason Havertape, Joshua NRC Farlett, Stephen Lamar Humberstone, Matthew NRC Liu, Kaven Hanna, John NRC Ratchford, Andy Brinsfield, Wes Deese, Rick NRC Rodriguez, Reinaldo NRC Khanna, Meena NRC Werkheiser, David NRC Brown, Adrienne NRC Mulhern, Isaac W DeMoss, Gary PSEG Szews, Heather Davis Duke Budnitz, Robert Ratnagaran, Benny J.
Dawson, Steven M Bream, Jeff NRC Balian, Harry PSEG Eggers, Shannon INL Presley, Mary EPRI
Apostolakis, George MIT Mount, Brian L Dominion Biro, Mihaela NRC Leech, Matthew NRC Stoesz, Alex P.
Adsit, Creighton S Dominion Stowell, Valerie Herrero Santos, Roberto Weerakkody, Sunil NRC Murphy, Martin C Xcel Energy Kozak, Laura NRC Ferrante, Fernando EPRI Sandal, Shane NRC Medina, Ricardo Schwab, Alexander NRC Julka, Anil K. NextEra Energy Henneke, Dennis GE Schairer, Mark EPM, Inc Burg, Rob EPM, Inc Sicard, Paul Entergy Ratchford, Andrew Jensen Hughes Dolan, Bradley TVA Carr, Michelle APS