ML24149A368

Request for NAC International Magnastor Cask System Amendment 15 - Accepted for Review - Cost Activity Code/Enterprise Project Identification Number 001028/L-2023-LLA-0143

ML24149A368
Person / Time
Site:	07201031
Issue date:	06/05/2024
From:	Donald Habib Storage and Transportation Licensing Branch
To:	Baldner H NAC International
References
CAC 001028, EPID L-2023-LLA-0143
Download: ML24149A368 (1)

Text

Heath M. Baldner, Director Licensing Engineering NAC International 2 Sun Court, Suite 220 Peachtree Corners, GA 30092

SUBJECT:

REQUEST FOR NAC INTERNATIONAL MAGNASTOR CASK SYSTEM AMENDMENT NO. 15 - ACCEPTED FOR REVIEW - COST ACTIVITY CODE/ENTERPRISE PROJECT IDENTIFICATION NOS. 001028/

L-2023-LLA-0143

Dear Mr. Baldner:

By letter dated August 29, 2023, (Agencywide Documents Access and Management System (ADAMS) Accession Number ML23241B053), as supplemented on October 26, 2023 (ML23300A138), you submitted an application to the U.S. Nuclear Regulatory Commission (NRC) for the amendment of the MAGNASTOR Cask Storage System certificate of compliance.

In your application you requested that the NRC amend the certificate of compliance with the following changes:

Add a new variation of the Lightweight MAGNASTOR Transfer Cask (LMTC) Reduced Width LMTC.

Add a new concrete cask design known as CC8. CC8 is based on the CC7 configuration and uses high density concrete for enhanced shielding.

Increase the maximum system heat load capacity.

Add new pressurized-water reactor (PWR) loading patterns L, M, and N, (Pattern N is a short loading pattern).

Add a Thermal Shunt to allow for short loading patterns.

Add new BWR loading patterns E, and F.

Remove 5 percent Burn Up "penalty".

Increase PMTC Heat Load (30kW to 35.5kW including Preferential Loading Pattern B)".

Revise previously approved drawings for the; Concrete Cask for CC8, PMTC, and LMTC.

Revise Technical Specification, Appendix A to include increased heat loads and loading patterns.

Revise Technical Specification, Appendix B to include increased heat loads and loading patterns and removal of cool time tables B2-13 through B2-43.

We have completed the acceptance review of your application and determined that it contains sufficient technical information in scope and depth. Therefore, your application has been accepted for detailed technical review. Your application has been assigned Cost Activity Code (CAC) No./Enterprise Project Identification (EPID) No. 001028/L-2023-LLA-0143. Please June 5, 2024

H. Baldner 2

reference these numbers and Docket No. 72-1031 in future correspondence associated with this request.

The acceptance review identified the following observation:

RSI 1 Provide calculations and analysis results of the MAGNASTOR PWR configuration during long term storage and short term-operations that justify the assumption of turbulent flow in the Transportable Storage Canister (TSC) downcomer region as well as bottom and top plenums.

Section 4.14.1.1.1 of the safety analysis report states that the helium downcomer region is modeled as turbulent for the TSC models of the PWR configuration. The staff reviewed MAGNASTOR computational fluid dynamics model (CFD) and noticed that, in addition to the downcomer region being characterized as turbulent flow, the bottom and top plenum are also assumed to be in the turbulent flow regime. In order to properly characterize and justify the use of turbulent model in these TSC regions, the applicant needs to obtain Rayleigh and Reynolds numbers for helium flow. For proper helium flow regime characterization, both numbers are needed because this is a buoyancy-driven flow. A Reynolds number of at least 2300 and Rayleigh number of at least 1x109 would indicate the flow is in the turbulent regime. Otherwise, the flow would be laminar.

The staff needs this information to have assurance that predicted temperatures remain below allowable limits during long term storage and short-term operations. The staff noticed that the results provided in the amendment application show very small margin against the allowable limit. Predicted temperatures did not include any uncertainty quantification (such as modeling error, numerical error, or input error).

This information is needed to determine compliance with Title 10 of the Code of Federal Regulations (10 CFR) Section 72.236(b), and 10 CFR 72.236(f)

Please note that the NRC staffs technical review of your submittal may identify issues that could require that you provide additional information. Based on our preliminary evaluation and projection of current review schedules, we anticipate completing our formal review by [month, year]. The schedule includes the issuance, if needed, of a request for additional information (RAI) by September 10, 2024, and, provided that we receive your responses to the RAI within 30 days after its issuance, we anticipate issuing the certificate of compliance/safety evaluation report by June 2025. Please note that these dates could change depending on the findings of our technical review, urgent assignments, or other factors, such as whether your responses to the RAI are or not adequate. The NRC staff estimates that completing the review of your submittal will require approximately 1,570 staff hours which corresponds to about $471,000. We will promptly communicate significant schedule and/or cost changes, if any.

In accordance with 10 CFR Part 2, Agency Rules of Practice and Procedure, a copy of this letter will be available electronically for public inspection in the NRC Public Document Room (PDR) or from the Publicly Available Records component of the NRCs ADAMS. ADAMS is accessible from the NRC website at http://www.nrc.gov/reading-rm/adams.html. The PDR is open by appointment. To make an appointment to visit the PDR, please send an email to PDR.Resource@nrc.gov or call 1-800-397-4209 or 301-415-4737, between 8 a.m. and 4 p.m.

eastern time (ET), Monday through Friday, except Federal holidays.

H. Baldner 3

If you have any questions regarding this communication, please contact me at 301-415-1035, or via email to Donald.Habib@nrc.gov.

Sincerely, Donald Habib, Project Manager Storage and Transportation Licensing Branch Division of Fuel Management Office of Nuclear Materials Safety and Safeguards Docket No.: 72-1031 Certificate No.: 1031 CAC No. 001028 EPID No. L-2023-LLA-0143 Signed by Habib, Donald on 06/05/24

H. Baldner 4

SUBJECT:

REQUEST FOR NAC INTERNATIONAL MAGNASTOR CASK SYSTEM AMENDMENT NO. 15 - ACCEPTED FOR REVIEW - COST ACTIVITY CODE/ENTERPRISE PROJECT IDENTIFICATION NOS. 001028/

L-2023-LLA-0143 DATED: June 5, 2024 DISTRIBUTION:

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CTCFB BC (A)

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