ML21298A222
| ML21298A222 | |
| Person / Time | |
|---|---|
| Issue date: | 10/25/2021 |
| From: | Holtec |
| To: | Office of Nuclear Material Safety and Safeguards |
| C JACOBS NRC/NMSS/DFM/STLB 3014156825 | |
| References | |
| Download: ML21298A222 (8) | |
Text
www.holtec.com Amendment to Incorporate Topical Report For Allowance of Candidate Heat Load Patterns - HI-STORM 100
www.holtec.com l Page 2
Background
Holtec submitted the request for approval of a topical report Report outlines a methodology for the thermal evaluation of heat load patterns in the MPC Approved in September 2021 Holtec now plans on submitting an amendment to incorporate this topical report
www.holtec.com l Page 3 Proposed CoC Changes -
App A/C
www.holtec.com l Page 4 Proposed CoC Changes -
App A/C
www.holtec.com l Page 5 Proposed CoC Changes -
App B/D
www.holtec.com l Page 6 Proposed FSAR Updates Added a section for Topical Report Implementation Covers impacts of the Topical Report on:
Structural FSAR structural analyses use calculated temperatures If heat load patterns developed under topical report calculate increased temperatures, these temperatures should be reviewed under provisions of 72.48 to determine if change to structural analysis is acceptable without NRC approval Shielding - FQTs in CoC apply regardless of heat load pattern Change Control
www.holtec.com l Page 7 Proposed FSAR Updates -
Change Control Topical Report SER - Limitation 4.2 describes the model reviewed for the scope of the topical report as invariant FSAR and FSAR thermal model are allowed to be modified under 10CFR72.48 Therefore, change can be made to FSAR without NRC approval, if it meets the 10 CFR 72.48 criteria Then the topical report methodology can be applied Additional restriction applied that the results from the revised model must be demonstrated to have a lower PCT than those in the topical report when run for identical heat loads If this criterion is met, then the topical report can be applied to updated FSAR model
www.holtec.com l Page 8 Summary Candidate Heat Load Pattern Will the heat load pattern be used in a canister model identical to that identified in the TR?
Yes No Can the canister model be added to the FSAR under 72.48?
No Obtain NRC Amendment or utilize a different canister model Yes Update FSAR in accordance with 72.48 process Does the updated model calculate equal to or lower PCT than the TR model when run for the same heat load pattern?
No Yes Evaluate the candidate heat load pattern using the approved TR methodology Are the temperature results from the TR bounded by those used in the FSAR structural analysis No Can the structural evaluations in the FSAR be modified under 72.48?
No Obtain NRC Amendment or utilize a different heat load pattern Yes Document 72.48 screening/evaluation and update FSAR if necessary Are all TR acceptance criteria met?
No Yes Yes Document thermal heat load pattern in technical report Site choses fuel to meet allowable heat load pattern, confirming that fuel also meets all other applicable CoC requirements (for example, shielding)