The U.S. Nuclear Regulatory Commission (NRC) is amending its spent fuel storage regulations by revising the Holtec International HI- STORM Underground Maximum Capacity (UMAX) Canister Storage System listing within the "List of approved spent fuel storage casks" to include Amendment No. 2 to Certificate of Compliance (CoC) No. 1040. Amendment No. 2 adds new fuel types to the HI-STORM UMAX Canister Storage System and updates an existing fuel type description. Additionally, Amendment No. 2 updates Table 3-4 of Appendix B of the CoC to reflect correct terminology and makes editorial changes to Appendix B of the CoC to clarify the description of the top surface pad. Each of these changes is described in Section IV, "Discussion of Changes," in the SUPPLEMENTARY INFORMATION section of this document.