The NRC is issuing an Environmental Assessment and FONSI for an exemption request by Constellation Energy Generation, LLC (CEG) at LaSalle County Station (LSCS) in Illinois, approximately 75 miles southwest of Chicago. CEG seeks to maintain four already-loaded MPC-68M with continuous basket shims (CBS) in the HI-STORM 100 Cask System and to load four additional such canisters beginning June 2025, even though the CBS variant design was not properly authorized under CoC No. 1014, Amendment No. 8, Revision No. 1. The NRC concluded that the CBS basket change produces no significant radiological or non-radiological environmental impacts, issued a FONSI, and determined no EIS is warranted.12