Approval of Implementation Plans; State of Iowa; Elements of the Infrastructure SIP Requirements for the 2010 Nitrogen Dioxide National Ambient Air Quality Standard (NAAQS)

The Environmental Protection Agency (EPA) is taking direct final action to approve elements of a State Implementation Plan (SIP) submission, and an amended SIP submission from the State of Iowa for the 2010 Nitrogen Dioxide (NO2) National Ambient Air Quality Standard (NAAQS). 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.