The U.S. Nuclear Regulatory Commission (NRC) is amending its spent fuel storage regulations by revising the NAC International, Inc. MAGNASTOR[supreg] Storage System listing within the "List of approved spent fuel storage casks" to include Amendment No. 9 to Certificate of Compliance No. 1031. Amendment No. 9 revises the certificate of compliance to add a new concrete storage overpack; four new heat load zone patterns and their associated decay heats that are specific to Babcock and Wilcox 15x15 fuel assemblies; a new Babcock & Wilcox 15x15 hybrid fuel assembly type (BW15H5); and a new maximum enrichment for the BW15H2 hybrid fuel assembly, including a new minimum soluble boron concentration during loading and unloading operations and neutron absorber areal density. In addition, Amendment No. 9 makes non- technical changes to reorganize Appendix B of the technical specifications. These changes are discussed in more detail in the "Discussion of Changes" section of this direct final rule.