ML23097A061

Enclosure - Clarification Call 04-03-2023

ML23097A061
Person / Time
Site:	Holtec
Issue date:	04/03/2023
From:	Storage and Transportation Licensing Branch
To:	Holtec
Shared Package
ML23097A059	List: ML23097A060 ML23097A061
References
Download: ML23097A061 (1)

Text

Summary of phone call with Holtec International (Holtec) on April 3, 2023, regarding request for additional information (RAI) on Holtecs application for HI-STORM 100 Amendment No. 18:

RAI discussed below:

• RAI 4-1, specifically item e - Holtec needed some clarification regarding all 72.48 changes, including those made for prior fuel patterns. Holtec just wants to make sure they understand exactly what the NRC reviewer is asking. Holtec thinks they agree in principle, but would like to confirm their understanding.

NRC seeking that all 72.48 changes related to the TR be considered for the cumulative effects of those 72.48 changes and their impact on component temperatures and PCT, considering that there potentially could be multiple successive uses of the TR to develop new heat loading patterns.

Resolution: The 72.48 changes are just for use in the systems being loaded.

• RAI 4 Holtec wanted to confirm unique values for loading patterns.

NRC not sure if Holtec is confirming that that unique values will be bounded by existing values in the TR? Or if existing bounding values in TR will be changed to unique values?

Resolution: Holtec to provide clarification in FSAR Section 1.0.3.1.

• RAI 4 Holtec requested clarification of use of 72.48s and existing process for changes involving technical discipline reviews.

NRC seeking clarification in the FSAR. Not seeing in Section 1.0.3.1.

Resolution: Holtec will follow 72.48. That process will determine if amendment is needed or not.

If cannot meet 72.48 conditions, process stops. Holtec will add this clarification.

• RAI 4 Holtec stated that existing FSAR has mesh studies, and asked if TR approved methodology didnt require uncertainty evaluation?

Is Holtec stating that the TR approved methodology didnt require uncertainty evaluation, and thus the FSAR has mesh studies to account for the uncertainty?

Resolution: Holtec has conducted mesh studies and sensitivity studies for PCT limits. Holtec stated that the TR did not require uncertainty evaluations. Holtec will provide brief summary and pointers in the FSAR as to what mesh studies were conducted and whether grid convergence index (GCI) will be recalculated.

• RAI 4 Holtec requested minor clarification on backfill for heat load limits.

NRC asked if Holtec is providing clarifications (that Holtec believes is minor)? Or is Holtec requesting NRC to provide minor clarification?

Resolution: Similar concept to RAI 4 -2. TR states how the backfill limits will be calculated in

Enclosure accordance with Section 2.3.6 of the TR. Holtec will provide within the TS bases by pointing to specific sections of the TR for clarification.

• RAI 4 Holtec clarified their understanding that the TR approved the thermal model for a list of MPCs and describes the methodology for vacuum drying / cyclic drying.

NRC requesting further clarification during call on what Holtec is asking.

Resolution: Holtec stated that Table 2.3 of the TR provides values for PWR and BWR, which are bounding for the systems referenced in the TR SE.

• RAI 4 Holtec clarified their understanding that the effects of elevation are already addressed in FSAR and not required to be re-evaluated as part of the TR methodology.

Holtec states effects of elevation are addressed in the FSAR.explain that. How is this addressed in CoC implementation?

Resolution: Holtec stated that every loading pattern will be evaluated for the effect of site elevations as described in FSAR section 4.4. Holtec will expand on FSAR section 4.4. 4.3 that will consider the effects of the TR methodology.

• Holtec stated that they will request separate clarification call for RAI 6-1.