ML24059A418
| ML24059A418 | |
| Person / Time | |
|---|---|
| Issue date: | 03/11/2024 |
| From: | King D Licensing Processes Branch |
| To: | Gerond George Licensing Processes Branch |
| References | |
| Download: ML24059A418 (5) | |
Text
March 11, 2024
MEMORANDUM TO: Gerond A. George, Chief Licensing Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
FROM: Daniel G. King, ATF Project Manager /RA/
Licensing Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
SUBJECT:
SUMMARY
OF THE FEBRUA RY 26 TO 27, 2024, PHENOMENON IDENTIFICATION AND RANKING TABLE PANEL DISCUSSION ON HIGH BURNUP FUEL DISPERSAL AND ITS CONSEQUENCES RANKINGS PUBLIC MEETING
From February 26, 2024, to February 27, 2024, the U.S. Nuclear Regulatory Commission (NRC) staff and Information System Laboratories, Inc. (ISL) held a hybrid phenomenon identification and ranking table (PIRT) panel public meeting with representatives from the nuclear industry to discuss high burnup uranium dioxide fuel fragmentation, relocation, and dispersal (FFRD). The purpose of the meeting was to provide an opportunity for the PIRT panel to complete phenomena identification and ranking tables related to reactivity-initiated accident phenomena.
This was a follow-up to the December 2023 (Agencywide Documents and Management System (ADAMS) Accession No. ML23352A274) and January 2024 (Accession No. ML24023A577)
PIRT panel meetings. The meeting notice can be found in ADAMS under Accession No. ML24057A096.
Key observations from the meeting discussions:
The PIRT panelists noted that fuel dispersal during a postulated reactivity-initiated accident (RIA) would be more limited than during a postulated loss-of-coolant accident.
Fuel rod failure during a postulated RIA depends strongly on the core loading pattern.
High burnup fuel is more susceptible to failure when placed near high-powered, lower-burnup assemblies. Existing methodologies can capture the core power distribution with a high degree of accuracy.
CONTACT: Daniel G. King, NRR/DORL 301-415-1233
James Corson, RES/DSA 301-415-2458
G. George
Transient fission gas release during an RIA both influences the likelihood of fuel rod failure and the potential magnitude of radionuclide release. While some transient fission gas release data exists, there is significant uncertainty in the results.
Fuel fragment release to the reactor coolant system could potentially result in energetic fuel-coolant interactions. Note that exis ting NRC guidance includes limits to prevent catastrophic fuel rod failure that could cha llenge core coolability. However, these limits are meant to prevent release of molten fuel and do not explicitly consider the impact of solid fuel fragments. See Section C.6 of Regulatory Guide 1.236 (Accession No. ML20055F490).
The following schedule going forward was agree upon by NRC staff, ISL, and panelists.
February 28, 2024 Panel members provide their contributions to the conclusions section of the draft report.
February 29, 2024 ISL will send an updated draft of the report to the panelists for their review.
Mid-March, 2024 The panel meets to discuss their final comments on the draft report.
Late-March, 2024 ISL submits draft final report to NRC for publication. NRC will release the draft report publicly while it prepares the report for publication as a NUREG/CR.
There were four public comments received during the public comment period. First a member of the public asked the NRC staff about the logistics of the PIRT process and the connection to previous PIRT exercises. The NRC staff noted that previous Accident Tolerant Fuel PIRTs can be found at: https://www.nrc.gov/reactors/power/atf/pirt.html, noting this exercise focused on high burnup uranium dioxide FFRD. A member of the public then asked a series of questions related to the potential development of hydrogen during hypothetical accident scenarios. Next, a member of the public commented on the higher burnup connection to increased enrichment.
Lastly, a member of the public asked several technical questions regarding the control rod drive mechanism for boiling water reactors. The PIRT panel provided additional information on the control rod drive mechanism (Accession No. ML12158A334). The NRC staff acknowledged all comments and questions from the public and will take them into consideration.
No regulatory decisions were made in the meeting.
Enclosures:
- 1. List of Attendees
List of Attendees
PHENOMENON IDENTIFICATION AND RANKING TABLE PANEL DISCUSSION ON HIGH BURNUP FUEL DISPERSAL AND ITS CONSEQUENCES RANKINGS PUBLIC MEETING February 26 to 27, 2024
U.S. Nuclear Regulatory Commission (NRC)
First Name Last Name Kristy Bucholtz Shawn Campbell James Corson Elijah Dickson Hossein Esmaili Daniel King Joseph Messina Carla Roque-Cruz Ashley Smith Chris Van Wert
Non-NRC First Name Last Name Organization (if provided)
Don Algama U.S. Department of Energy Kevin Barber Westinghouse Electric Company Jana Bergman Carl Beyer Pacific Northwest National Laboratory Francis Bolger Electric Power Research Institute Mary Beth Brangan Nathan Capps Oak Ridge National Laboratory Connie Kline Dave Kropaczek Veracity Nuclear Edwin Lyman Union of Concerned Scientists Wade Marcum Oregon State University Alred Meyers Brian Mount Dominion Energy Kurshad Muftuoglu EPRI Vesselin Palazov Information System Laboratories, Inc. (ISL)
Harold Scott Gretar Tryggvason Johns Hopkins University Michael Tudisco Constellation Nuclear Kalene Walker Jason Williams ISL Wolfgang
Note: Attendance list based on Microsoft Teams participant list. This list does not include individuals who did not provide their last name either in registering for the meeting or by a follow-up email.
Enclosure 1 Table of Contents for the Draft FFRD PIRT Report
- 1. INTRODUCTION
1.1 Background
1.2 Objectives
- 2. PHENOMENA IDENTIFICATION AND RANKING METHODOLOGY 2.1 Technological Scope and Licensing Events Outline 2.2 PIRT Elicitation Process Outline 2.3 PIRT Generation Approach
- 3. PHENOMENA IDENTIFICATION AND RANKING TABLES 3.1 PIRT on High Burnup FFRD and Its Consequences for Whole-Core Thermal Events 3.1.1 High Burnup FFRD PIRT for Whole-Core Thermal Events (LOCAs) 3.1.2 Summary of Panel Discussions 3.1.3 Key PIRT Panel Considerations 3.2 PIRT on High Burnup FFRD and Its Consequences for Local Core Events 3.2.1 High Burnup FFRD PIRT for Local Core Events (RIAs) 3.2.2 Summary of Panel Discussions 3.2.3 Key PIRT Panel Considerations 3.3 PIRT on High Burnup FFRD and Its Consequences for Fuel Handling Accidents 3.3.1 High Burnup FFRD PIRT for Fuel Handling Accidents 3.3.2 Summary of Panel Notes 3.3.3 Summary of Panel Deliberation Insights 3.3.4 Key FHA PIRT Panel Considerations
- 4.
SUMMARY
AND CONCLUSIONS
APPENDIX A: FFRD PIRT PANEL MEMBERS APPENDIX B: FFRD PIRT on High Burnup FFRD and Its Consequences for Whole-Core Thermal Events with All Panel Votes APPENDIX C: PIRT on High Burnup FFRD and Its Consequences for Local Core Events (RIAs) with Panel Votes APPENDIX D: PIRT on High Burnup FFRD and Its Consequences for FHAs with Panel Votes
Enclosure 2
ML24059A418 (Meeting Summary)
OFFICE NRR/DORL/LLPB PM RES/DSA/FSCB NRR/DORL/LLPB LA RES/DSA/FSCB BC NAME DKing JCorson DHarrison HEsmaili DATE 02/28/2024 02/29/2024 02/29/2024 03/11/2024 OFFICE NRR/DORL/LLPB BC NRR/DORL/LLPB PM NAME GGeorge DKing DATE 03/04/2024 03/11/2024