SIPs are submitted by individual states in accordance with explicit requirements set forth in the Clean Air Act (CAA). The requirements have been interpreted via regulations and guidance promulgated by EPA. The CAA requires each state to produce a single comprehensive SIP; however, in practice, each state produces a separate implementation plan for each criteria pollutant, because of the timing and pollutant-specific requirements set
There are more than 550 federally recognized tribes and more than 300 reservations in the United States. Indian tribes and individuals own approximately 55.4 million acres of land in the contiguous United States (Getches et al. 1998). The 1990 CAA Amendments authorized EPA to “treat tribes as states” for purposes of developing, administering, and enforcing air quality regulations within reservation boundaries, irrespective of land ownership (42 USC § 7601(d)(2)(B)). In doing so, Congress recognized the inherent sovereignty of tribes with respect to their land and members. Congress also delegated to the tribes regulatory authority over nonmembers operating on land within reservation boundaries.
Pursuant to the CAA, in February 1998, EPA promulgated its tribal authority rule, specifying requirements for tribal eligibility to administer air programs (40 CFR 49). To be eligible, a tribe must apply to the EPA regional administrator and demonstrate that it is “reasonably” capable of administering its program in a manner consistent with the terms and purposes of the CAA. Tribes may develop a full tribal implementation plan (TIP) and seek authority to carry out all the functions that states perform under the act, but they are not required to do so. EPA’s regulations allow tribes to assume primacy over a subset of regulatory functions and to expand their authority gradually. EPA also has the flexibility to alter deadlines for plan submittal and other regulatory requirements.
In 1999, the Gila River Indian Community became the first tribe to become eligible for “treatment as a state” status. To date, 14 tribes have received eligibility to implement parts of the CAA. The Mohegan tribe submitted a TIP to EPA in FY 2002, while the Pequot, St. Regis Mohawk, and Gila River have TIPs in progress (EPA 2003d). The tribal council of the Gila River Indian Community adopted ordinances in March 2002 comprising the first section of its TIP.
On the basis of a telephone survey of 156 of the 237 federally recognized tribes in the Western Regional Air Partnership (WRAP) region, 60 tribes in this region have some form of air quality program. The scope of activities ranges from education and outreach to monitoring, emissions inventory development, and source permitting (ITEP 2001). Twenty-eight of the surveyed tribes had an emissions inventory and 51 tribes performed some air quality or meteorological monitoring. The survey suggested that if resources were available, the level of activity could double in the next few years. For example, 62 tribes indicated an interest in starting an air monitoring program in the next few years (ITEP 2001).
Tribes, like states, are eligible under the CAA for federal grants to support air quality monitoring and management efforts. EPA began seeking tribal participa-