ML24157A052
| ML24157A052 | |
| Person / Time | |
|---|---|
| Site: | Holtec |
| Issue date: | 06/17/2024 |
| From: | Holtec |
| To: | Office of Nuclear Material Safety and Safeguards |
| Shared Package | |
| ML24157A048 | List: |
| References | |
| EPID L-2024-LRM-0051 | |
| Download: ML24157A052 (1) | |
Text
www.holtecinternational.com HI-STORM 100 Amendment 19 Pre-Application Presentation to NRC April 2024
l Page 2 Presentation Agenda Summary of Amendment Request Discussion of Expedited Amendment Questions Page 2-Holtec Information
l Page 3 Summary of Amendment Request HI-STORM 100 Amendment 19 request will be a small focused amendment relating to the tipover methodology for Metamic-HT baskets Amendment request is a corrective action from the inspection action related to the CBS baskets HI-STORM FW Amendment 7 provides the road map for this amendment
l Page 4 Summary of Amendment Request The amendment request will update Chapters 2 and 3 of the SAR to include a revised methodology for the tipover calculations for Metamic-HT baskets (MPC-68M and MPC-32M, all variants)
A new acceptance criteria based on stress will be added LS-DYNA models will be used to show compliance with this new criteria
l Page 5 Summary of Amendment Request Stress criteria based on 90% of ultimate stress Details of LS-DYNA model and combinations of canisters and overpacks to be discussed in proprietary session No change to any other analyses, very narrow focus on non-mechanistic tipover
l Page 6 Expedited Amendment This amendment request is needed due to the enforcement action related to the CBS variant baskets Sites are interested in loading these baskets and cannot without licensing action Exemption requests are on-going for near term users Efficient approval of this amendment will prevent additional exemption requests Using the same methodology as HI-STORM FW Amd 7 that is hopefully in the final steps of NRC approval Want to figure out the best process to move forward efficiently considering the safety significance to resolve the compliance issue Focus is on quickly resolving this issue, but could inform a future process for resolving non-safety significant compliance issues
l Page 7 Expedited Amendment Office of Nuclear Reactor Regulation (NRR) has a process called Risk-Informed Process for Evaluations RIPE to address low safety significance issues Reviewed presentations and NRC memo on that process May be difficult to apply directly to Part 72 scenario, relies heavily on PRA results PRA evaluated prior to submittal to demonstrate that it is in fact a very low safety significance issue Part 72 does not have individualized cask design PRAs
l Page 8 Expedited Amendment Part 72 doesnt have PRA in the same way as Part 50 However, we have a memorandum from NRC staff concluding, the consequences of a basket failure have a very low safety significance provided the confinement boundary is maintained.
The revised tipover analyses do not make any changes related to the confinement boundary Is there a way to use this safety conclusion approved by NRC staff to expedite the technical review process similar to RIPE?
l Page 9 Expedited Amendment Holtec understands that NRC has been implementing a risk tool on new applications The use of that tool is slightly unclear to applicants, but can that be used to expedite review time of a very low safety significant change?
Can Holtec help by including evaluation of the application against that risk tool at submittal?
This would somewhat echo the RIPE process where the applicant does the work up front to demonstrate low safety significance Would need some clearer examples of how NRC staff has implemented risk tool to date Risk tool might be an option to leverage existing work and not create a new process from scratch
l Page 10 Schedule Holtec is committed to submitting this application by the end of June Given the high interest levels and need for the approved amendment to avoid future exemption requests, requested schedule is fully effective by May 2025 This would mean a completed technical review by approximately December 2024
l Page 11 Questions and Discussion Page 9-Holtec Information