SIPs - State Implementation Plans
States comply with Clean Air Act requirements by developing implementation plans to address specific air quality issues. There must be "state implementation plans," (SIPs) for attainment of primary and secondary national ambient air quality standards, (42 U.S.C. § 7410 (CAA § 110)), Prevention of Significant Deterioration (42 U.S.C. § 7471 (CAA § 161)), and for the protection of visibility. States are required to consult with the NPS and other federal land managers if federal lands might be affected, with more specific consultation requirements for visibility protection plans.
All states have some authority to implement the Clean Air Act within their boundaries. Information about state programs is available on the website of the State and Territorial Air Pollution Program Administrators/Association of Local Air Pollution Control Officials (STAPPA and ALAPCO). That site also contains links to all state air agencies, through which state air quality laws and regulations can be accessed.