A major goal of the Clean Air Act 1 (hereinafter CAA or Act ) is to protect and enhance the quality of the Nation\u27s air resources. 2 The Act uses a two tiered approach to accomplish this goal. First, the Act focuses on the national attainment and maintenance of National Ambient Air Quality Standards (NAAQS) for criteria pollutants, 3 and second, the Act also sets specific standards for known hazardous air pollutants (HAPS) 4 . The Act emphasizes throughout its text that air quality problems are national in scope and often cross state boundaries. 5 Congress clearly intended that enforcement of programs to improve air quality be a cooperative effort of state and federal governments. 6 Courts also have recognized for decades the necessity of a federal enforcement presence in the effort to improve air quality nationally. As the D.C. Circuit Court noted, EPA ... is the ultimate supervisor, responsible for approving state plans and for stepping in, should a state fail to develop or to enforce an acceptable plan... EPA is to ensure national uniformity where needed, for example, to ensure that states do not compete unfairly for industry by offering air quality standards that are too lax to bring about needed improvement in the air we breathe. 7 An important component of many federal environmental laws is federal enforceability. The federal enforceability 8 of state air quality limitations or controls on sources requires that the Administrator of the EPA, not solely state or local authorities, enforce emission ..
