Comment submitted by Indiana Department of Environmental Management (IDEM)

Summary: The Indiana Department of Environmental Management (IDEM) supports the proposed revisions to New Source Review air permitting regulations because they provide clarity, reduce administrative burdens, and offer greater certainty for economic development. While supporting the rule, IDEM suggests specific language to prevent applicants from using preparatory construction costs to influence BACT/LAER analyses and recommends that Congress eventually provide legislative clarity on the "commence construction" definitions.