The nonattainment sections of the Clean Air Act are at: 42 U.S.C. §§ 7501 - 7515 (CAA §§ 171 - 193).
Some parks are located in areas where air quality is worse than one or more standards set to protect public health. If an area is designated "nonattainment" for a particular pollutant, more stringent requirements apply for sources of that pollutant. This means an area may be subject to the PSD provisions for some pollutants and the nonattainment requirements for other pollutants. As with Class II and III areas, the CAA does not generally establish an explicit role (other than consultation) for the federal land manager. One limited exception provides for federal land manager review of a major new or modified source proposing to locate in a nonattainment area in one of the 36 states covered by EPA's visibility regulations, if the source might affect the visibility of a mandatory Class I area.
Nevertheless, the nonattainment title of the CAA provides opportunities to seek park protection in various public proceedings. For example, the state must hold a public hearing prior to promulgating a nonattainment implementation plan, which is a plan for attaining all national ambient air quality standards "as expeditiously as practicable," most primary standards by 1982, and primary standards for ozone and carbon monoxide by 1988. (Since many areas have not yet attained the ozone and carbon monoxide standards, Congress may amend the CAA to extend this deadline and possibly to revise other aspects of the act.)
The nonattainment plan must:
- demonstrate "reasonable further progress" toward the national ambient standards in the interim;
- provide for reasonable available control technology on sources in the area;
- analyze effects on air quality, welfare, health, society, and economics; and
- require a public hearing prior to issuing a permit for a new source.
To obtain a permit, new sources in urban areas must secure from other facilities "emission offsets" greater than the new source's proposed emissions unless the applicable implementation plan otherwise "accommodates" the source. In addition, a new source's control technology must comply with the "lowest achievable emission rate" (LAER) for such a source.