Partial Approval and Partial Disapproval of Implementation Plans; State of Iowa; Infrastructure SIP Requirements for the 2008 Ozone National Ambient Air Quality Standard

The Environmental Protection Agency (EPA) is proposing to partially approve and partially disapprove elements of a State Implementation Plan (SIP) submission from the State of Iowa for the 2008 National Ambient Air Quality Standards (NAAQS) for ozone. Infrastructure SIPs address the applicable requirements of Clean Air Act (CAA) section 110, which requires that each state adopt and submit a SIP for the implementation, maintenance, and enforcement of each new or revised NAAQS promulgated by the EPA. These SIPs are commonly referred to as ``infrastructure'' SIPs. The infrastructure requirements are designed to ensure that the structural components of each state's air quality management program are adequate to meet the state's responsibilities under the CAA.