Ind. Code § 13-17-5-10
Not later than December 31, 2025, the department shall do the following:
(2) Identify air pollution reduction or regulatory relief strategies that can do the following with respect to the federal Clean Air Act (42 U.S.C. 7401 et seq.), as amended by the federal Clean Air Act Amendments of 1990 (P.L.101-549):
(E) Result in the withdrawal of Lake County and Porter County from the Metropolitan Chicago Interstate Air Quality Control Region.
In identifying strategies under subdivision (2), the department must coordinate with the United States Environmental Protection Agency.
As added by P.L.187-2025, SEC.1.