(a) On September 30, 1999, Indiana submitted the State plan for implementing the Federal Large Municipal Waste Combustor (MWC) Emission Guidelines to control emissions from existing MWCs with the capacity to combust greater than 250 tons per day of municipal solid waste. The enforceable mechanism for this plan is a State rule codified in 326 Indiana Administrative Code (IAC) 11-7. The rule was adopted on September 2, 1998, filed with the Secretary of State on January 18, 1999, and became effective on February 17, 1999. The rule was published in the Indiana Register on March 1, 1999 (22 IR 1967).

(b) On August 24, 2007 (with corrections submitted on July 29, 2008), Indiana submitted a revised State plan as required by Sections 129(a)(5) and 129(b)(2) of the Act. The revised (Phase II) State plan implements amendments to 40 CFR part 60, subpart Cb published in the Federal Register on May 10, 2006. The Phase II State plan includes an amendment to State Rule 326 IAC 11-7 that was adopted by Indiana on February 7, 2007.