Air Plan Approval; Indiana; Base Year Emissions Inventory and Emissions Statement Rule Certification for Lake and Porter Counties for the 2008 Ozone Standard

The Environmental Protection Agency (EPA) is proposing to approve two State Implementation Plan (SIP) submissions from the Indiana Department of Environmental Management (IDEM), both dated June 15, 2016. The first addresses emissions inventory requirements for the Indiana portion of the Chicago-Naperville, Illinois-Indiana-Wisconsin (IL-IN-WI) ozone nonattainment area under the 2008 ozone National Ambient Air Quality Standard (NAAQS). The Clean Air Act (CAA) requires emissions inventories for all ozone nonattainment areas. The documented emissions inventory included in Indiana's June 15, 2016, submission meets this CAA requirement. The second submission provides Indiana's certification that its existing Emissions Reporting Rule, previously approved by EPA under a prior ozone standard, satisfies the CAA emissions statement rule requirement for Lake and Porter Counties under the 2008 ozone standard.