ML22133A201
| ML22133A201 | |
| Person / Time | |
|---|---|
| Site: | 99902041 |
| Issue date: | 06/02/2022 |
| From: | Ngola Otto Licensing Processes Branch |
| To: | Richard Chang Licensing Processes Branch |
| Otto N, NRR/DORL/LLPB | |
| Shared Package | |
| ML22122A048 | List: |
| References | |
| Download: ML22133A201 (6) | |
Text
June 2, 2022 MEMORANDUM TO:
Richard Chang, Chief Licensing Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM:
Ngola A. Otto, Project Manager /RA/
Licensing Projects Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
SUBJECT:
SUMMARY
OF MAY 4, 2022, PARTIALLY CLOSED MEETING BETWEEN FRAMATOME INC. AND THE U.S. NUCLEAR REGULATORY COMMISSION ON A HIGHER BURNUP TOPICAL REPORT PRE-SUBMITTAL DISCUSSION REGARDING FUEL FRAGMENTATION RELOCATION AND DISPERSAL On May 4, 2022, the U.S. Nuclear Regulatory Commission (NRC) staff held a partially closed teleconference meeting via Microsoft Teams (Open Session and Closed Session) with representatives from Framatome Inc. (Framatome). The purpose of the meeting was for the NRC staff and the Framatome representatives to conduct pre-submittal discussions on a higher burnup topical report (TR) regarding Fuel Fragmentation Relocation and Dispersal (FFRD), and impacts on the loss-of-coolant accident (LOCA) evaluation models (EMs) and rupture analysis.
The meeting notice is available in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML22109A120. Other, higher burnup TR related meetings were held with the NRC staff and Framatome representatives on August 20, 2020 (ADAMS Accession No. ML20335A115), November 16, 2020 (ADAMS Accession No. ML20343A028),
December 18, 2020 (ADAMS Accession No. ML20350B553), February 24, 2021 (ADAMS Accession No. ML21050A328), May 25, 2021 (ADAMS Accession No. ML21141A235), and September 15, 2021 (ADAMS Accession No. ML21256A006).
During the open session, the Framatome representatives provided a background of the applicable advanced codes and methods, scope of the future higher burnup TR submittal, and an introduction on the topics that would be discussed during the closed session, discussed later.
There was one question from a member of the public during the open session about the planned submittal date for the Framatome higher burnup TR. The NRC staff communicated that the TR submittal date is Framatome proprietary information.
CONTACT:
Ngola A. Otto, NRR/DORL 301-415-6695
During the closed session, the Framatome representatives and the NRC staff discussed Framatomes presentation on advanced fuel management increased burnup with FFRD, LOCA EMs, FFRD rupture analyses, and next steps including additional meetings on FFRD issues.
The NRC staff discussed a number of relevant topics during the closed session of the meeting, including the following:
Consistency of the approach with the requirement in Title 10 of the Code of Federal Regulations (10 CFR) 50.46, Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors, (b)(4), Coolable geometry, that the core remains amenable to cooling, or whether Framatome expects that an exemption to this regulation would be necessary when addressing FFRD phenomena.
Consistency of the approach with the evaluation model requirements in 10 CFR 50.46(a)(1) by either (i) applying realistic modeling approaches with an explicit estimate of uncertainty or (ii) conforming to the required and acceptable modeling features of appendix K to 10 CFR Part 50, Emergency Core Cooling System (ECCS)
Evaluation Models, or whether Framatome intends to seek an exemption to evaluation model requirements specified in 10 CFR 50.46(a)(1) when addressing FFRD phenomena.
Consistency of the material presented on slide 13 with the current ECCS acceptance criteria (e.g., 10 CFR 50.46(b)(2)).
Framatomes treatment of FFRD phenomena for the small break LOCA event.
The applicability of Framatomes existing fuel relocation model in its methodology for large break LOCA in regimes where experimental data currently available to the NRC staff is sparse or non-existent.
The consistency of Framatomes FFRD modeling with information in the NRCs Research Information Letter 2021-13 on Interpretation of Research on FFRD at high burnup (ADAMS Accession No. ML21347A940). Such as with respect to determining where fuel relocation occurs.
The proposed method of characterizing fuel assembly initial conditions with relevance to FFRD in a manner that would adequately assure compliance with the acceptance criteria of 10 CFR 50.46.
The proposed method of assuring consistency between plant operating conditions and analytical assumptions for FFRD fuel.
Consideration of rod-to-rod interactions, such as the contacting of adjacent rods following swelling and/or rupture, and the associated effects on heat transfer and subchannel flow blockage.
Consideration of core-wide impacts of high-burnup rods to experience increased swelling and rupture. Core designs supporting high-burnup operation may involve increased power levels and rod internal pressures for many average rods within the core. A large-scale increase in the swelling and rupture of such average rods could decrease the effective core flow area and increase the core pressure drop, potentially reducing the reflood rate below currently predicted values.
Code validation when addressing FFRD phenomena.
While Framatome responded verbally to most of the above issues during the meeting, the meeting purpose was to assist the NRC staff in understanding Framatomes planned submittal rather than achieving agreement and resolution of all issues. The NRC staff expects to continue dialogue with Framatome on these and other issues during future pre-submittal discussions and
the review of Framatomes planned TR. Framatome intends further interactions with the NRC staff as its TR is developed.
A list of the attendees is enclosed. The Framatome presentation materials, including this meeting summary can be found at ADAMS Package Accession No. ML22122A048.
Docket No. 99902041
Enclosure:
As stated
ML22122A048 (Package)
ML22133A201 (Summary)
ML22109A120 (Notice)
ML22122A051 (Open Session Presentation)
ML22122A049 (Closed Session - Proprietary Presentation)
ML22122A050 (Closed Session - Nonproprietary Presentation)
- via email OFFICE NRR/DORL/LLPB/PM*
NRR/DORL/LLPB/LA*
NRR/DORL/LLPB/BC*
NRR/DORL/LLPB/PM*
NAME NOtto DHarrison RChang NOtto DATE 05/16/2022 05/18/2022 06/02/2022 06/02/2022
Enclosure List of Attendees Partially Closed Meeting with Framatome and the Nuclear Regulatory Commission on Increased Burnup Topical Report Pre-Submittal Discussions on Fuel Fragmentation Relocation and Dispersal (FFRD)
May 4, 2022 2:00 pm - 5:00 pm NAME ORGANIZATION Kent Abel Framatome (Framatome)
Bob Baxter Framatome Andrei Burghelea Framatome Morris Byram Framatome Lisa Gerken Framatome Nathan Hottle Framatome John Klingenfus Framatome Will Maxson Framatome Jeff Reed Framatome Carl Stebbings Framatome Gordon Wissinger Framatome Matthew Bernard U.S. Nuclear Regulatory Commission (NRC)
Andrew Bielen NRC Mark Blumberg NRC Kristy Bucholtz NRC Richard Chang NRC James Corson NRC Elijah Dickson NRC Joseph Donoghue NRC Michael Franovich NRC Kevin Heller NRC NAME ORGANIZATION Todd Hilsmeier NRC Kevin Hsueh NRC John Lehning NRC Robert Lukes NRC Joseph Messina NRC Ngola Otto NRC Mathew Panicker NRC John Parillo NRC April Pulvirenti NRC Mary-Jane Ross-Lee NRC Ashley Smith NRC Michael Wentzel NRC Josh Whitman NRC Brandon Wise NRC Kent Wood NRC Don Algama Department of Energy (DOE)
Frank Goldner DOE Andrea Jennetta S&P Global - Platts