ML20287A455
| ML20287A455 | |
| Person / Time | |
|---|---|
| Issue date: | 10/15/2020 |
| From: | Jacqueline Thompson NRC/NRR/DEX/EXHB |
| To: | Michael Lee NRC/NRR/DEX/EXHB |
| Jenise Thompson 301-415-7000 | |
| References | |
| DG-4028 | |
| Download: ML20287A455 (5) | |
Text
October 15, 2020 MEMORANDUM TO: Michael P. Lee, Acting Chief External Hazards Branch Division of Engineering and External Hazards Office of Nuclear Reactor Regulation FROM: Jenise Thompson, /RA/
External Hazards Branch Division of Engineering and External Hazards Office of Nuclear Reactor Regulation
SUBJECT:
SUMMARY
OF SEPTEMBER 22, 2020, MEETING WITH THE NUCLEAR ENERGY INSTITUTE ON COMMENTS SUBMITTED ON DG-4028, VOLCANIC HAZARDS ASSESSMENT FOR PROPOSED NUCLEAR POWER REACTOR SITES On September 22, 2020, the U.S. Nuclear Regulatory Commission (NRC) held a Category 2 public meeting with representatives of the Nuclear Energy Institute (NEI) in an online webinar.
The purpose of the meeting was to discuss comments submitted by NEI on draft Regulatory Guide (DG) 4028, Volcanic Hazards Assessment for Proposed Nuclear Power Reactor Sites.
The meeting notice and agenda, dated September 11, 2020, are available in the Agencywide Documents Access and Management System (ADAMS) at Accession Number ML20265A360.
A list of attendees is provided as Enclosure 1.
BACKGROUND On July 21, 2020, NEI submitted comments on DG-4028 (see ML20213A749) and subsequently requested the opportunity to discuss these comments in a public meeting with the NRC staff.
NEI representatives presented information during the meeting that reiterated key points of their earlier submitted comments (see ML20265A196). Those comments included recommended changes to the conclusions and future actions, as well as a request that the NRC staff consider an additional opportunity for public comment before publishing the DG as a final Regulatory Guide (RG). Key comments from NEI were focused on the proposed use of geographic screening criteria, clarification of the risk-informed process and use of risk insights within the DG, concerns related to references to the International Atomic Energy Agency documents, and consideration of the risk-informed, performance-based approach in RG 1.233 and NEI 18-04.
The NRC staff presented several topics for further discussion based on their understanding of the NEI comments (see ML20265A242). Specifically, the NRC staff presentation focused on initial screening of volcanic hazards, the effects of volcanic hazards on the design and operation of nuclear power reactors, and the use of risk insights in a volcanic hazards analysis (VHA).
The NRC staff also posed several questions for additional discussion during the public meeting, including whether there were available studies or information related to performance of
structures, systems, or components (SSCs) that might be correlative to the physical and chemical demands of volcanic hazards.
MEETING
SUMMARY
Following their respective presentations, NRC staff and NEI representatives had an open discussion on the comments related to DG-4028 and the NRC staffs planned clarifications and revisions to the DG. Related to the screening of volcanic hazards, the NEI representatives questioned why the NRC did not consider or use the United States Geological Surveys (USGS)
National Volcanic Threat Assessment to develop geographic screening criteria. The NRC staff clarified that the USGS National Volcanic Threat Assessment is intended to inform and prioritize monitoring of volcanic hazards domestically and is not risk-informed. It also does not consider what are viewed as design basis events (DBE) and beyond design basis events (BDBE) for the purposes of NRC regulations. In this regard, the NRC staff noted that the USGS assessment only considered Holocene-age events (10,000 years ago), whereas the NRC has established the Quaternary Period (2.6 million years before present) as the time period of regulatory interest for consideration of external geophysical hazards. There was additional discussion on the distinction between DBE and BDBE related to volcanic hazards and potential effects on SSCs.
The staffs presentation on the initial screening of volcanic hazards noted that information from the regional (320 km) and site vicinity (40 km) investigations performed to satisfy the requirements of 10 CFR 100.23 could be used as reasonable screening criteria for volcanic hazards. Representatives from NEI asked the staff to clarify where the regional site investigation distance is specified. The NRC staff stated that the regional and site vicinity guidance is contained in RG 1.208 and NUREG-0800.
Following the formal staff and NEI presentations, the meeting was opened to questions from the public. One meeting participant asked the NRC staff why this action is being taken now and what the driving factors were in choosing to proceed with this DG at this time. In response, the NRC staff cited the 2017 passage of the Nuclear Energy Innovation Capabilities Act, the establishment of the National Reactor Innovation Center at the Idaho National Laboratory, and the reasonable expectation that proposed future sites may consider locations potentially affected by volcanic hazards as reasons for its decision to proceed with this action. The NRC staff also shared that a detailed regulatory analysis was performed to consider the prior reviews conducted for sites that included potential volcanic hazards to determine if the ad-hoc approach was still appropriate but determined that an RG was the optimal path forward.
Another meeting participant from the nuclear industry raised some questions about what the NRC staff would consider supplemental information to help provide greater specificity in the guidance document. The NRC staff clarified that the information provided in connection with the public meeting as well as any other available information provided would be considered supplemental information as the staff moves forward to revise and finalize the RG. Additionally, an industry attendee mentioned the possibility of some studies related to dust hazards impacts assessments that may be useful to the NRC in the revision of the DG.
Another meeting participant asked the NRC staff to clarify the timeline for revision and issuance of the guide. The NRC staff stated that the schedule for revising the guide was still under development but that a revised guide could be issued in the next 3 to 6 months, depending on several factors and internal process requirements. The NRC staff recognized the request from NEI for the opportunity for additional public comments prior to final issuance and will consider this request in the development of the schedule for completion.
The NRC staff also received several questions and comments related to the incorporation of the licensing modernization program (LMP) concepts and considerations for future 10 CFR Part 53 regulatory requirements. The NRC staff clarified that the guide is intended for use by any new reactor applicant using any reactor technology and as such, not all Part 53 concepts may be appropriate for inclusion in the guidance document. The NRC staff also received comments on how to evaluate cascading events in addition to initiating events, how a potential facility would respond not just to the initiating events but the entire event sequence, and how this could be incorporated into the guide. One meeting participant asked the NRC staff to clarify why a BDBE might be considered, noting the frequency cutoff for DBE and BDBE in RG 1.233, Guidance for a Technology-Inclusive, Risk-Informed, and Performance-Based Methodology to Inform the Licensing Basis and Content of Applications for Licenses, Certifications, and Approvals for Nin-Light Water Reactors, and NEI 18-04, Risk-Informed Performance-Based Guidance for Non-Light Water Reactor Licensing Basis Development. The NRC staff is considering all of these comments for possible incorporation in the guide.
The NRC staff also clarified that an applicant choosing to use a VHA process different from the one proposed in the draft guide would be reviewed on an ad-hoc basis because this and all RGs do not represent regulatory requirements and compliance with them is not required by potential applicants. The NRC staff also clarified that for an application that precludes consequences due to design considerations, the applicant should present an argument as to why the volcanic hazards would not affect the site for the staff to review, but again reiterated that following the guidance document is not a requirement of any new reactor applicant.
In closing, the NEI representatives reiterated the industrys desire for an additional opportunity to review and comment on the DG before issuing as final, possibly as either a second public comment period or another public meeting. The NRC staff responded that it will consider additional opportunities for public interactions as they work on the schedule to finalize the DG.
There were 24 attendees in addition to NRC staff and its contractors. Public Meeting Feedback forms were made available online to meeting participants, but no feedback forms were received.
Enclosures:
- 1. List of Attendees
ML20287A455 *via email NRR-106 OFFICE NRR/DEX/EXHB NRR/DEX/EXHB/BC NAME JThompson* MLee* (acting Branch Chief)
DATE 10/13/2020 10/15/2020 LIST OF ATTENDEES SEPTEMBER 22,2020 MEETING WITH THE NUCLEAR ENERGY INSTITUTE ON COMMENTS SUBMITTED ON DG-4028 Name Affiliation Name Affiliation Jenise Thompson NRC Jason Redd Southern Jennifer Tobin NRC Frances Pimentel NEI Miriam Juckett SwRI (Contractor to Deb Luschinger NuScale NRC)
Maryam Khan NRC Annie Nash Fluor Brittain Hill Consultant to the Joe Hegner NRC staff Laurel Bauer NRC Jana Bergman Curtiss Wright Michele Sampson NRC Cindy Williams NuScale Edward ODonnell NRC Kati Austgen NEI James Rubenstone NRC Nicole Schlichting Kairos Barbara Hayes NRC Gary Becker NuScale Dogan Seber NRC Mason Baker UAMPS Allen Fetter NRC Marc Nichol NEI Cliff Munson NRC Matt Warner Kairos Eric Oesterle NRC Mike Miller NuScale Joe Sebrosky NRC Kevin Pigg NuScale Andrea Veil NRC Jeff Perry TVA Rob Taylor NRC Rob Burg EPM-Inc John Segala NRC Richard Pease Westinghouse David Heeszel NRC Amir Afzali Southern Adam Malinowski Westinghouse Tammy Morin Holtec Jordan Hagaman Kairos Drew Peebles Kairos Dennis Henneke GE Enclosure