List of Approved Spent Fuel Storage Casks: Holtec International HI-STORM Flood/Wind Multipurpose Canister Storage System, Certificate of Compliance No. 1032, Amendment No. 5

The U.S. Nuclear Regulatory Commission (NRC) is confirming the effective date of July 27, 2020, for the direct final rule that was published in the Federal Register on May 13, 2020. The direct final rule amends the NRC's spent fuel storage regulations by revising the Holtec International HI-STORM Flood/Wind Multipurpose Canister Storage System listing within the "List of approved spent fuel storage casks" to include Amendment No. 5 to Certificate of Compliance No. 1032. Amendment No. 5 revises the certificate of compliance to: Add new heat load patterns and revise the minimum required cooling time for two multipurpose canisters (MPC-89 and MPC-37); add new fuel types to the approved contents; allow an exception to a code to permit use of certain duplex stainless steels; use an analysis model to revise the calculation for evaluating effective fuel conductivities; add the use of the damaged fuel isolator; add two versions of the standard variable weight transfer cask; add the option of using cyclic vacuum drying; and make changes to the final safety analysis report to add new types of fuel assemblies, add a definition to it and to the certificate of compliance, and add the required shielding evaluation to Section 5.4.8. In addition, Amendment No. 5 makes several clarifications and minor changes.