SIP - General Page
SIPs & TIPs: STATE IMPLEMENTATION PLANS (SIPs) AND TRIBAL IMPLEMENTATION PLANS (TIPs)
An implementation plan is a set of programs and regulations to assure healthy air quality through the attainment and maintenance of the National Ambient Air Quality Standards (NAAQS). These plans can be developed by States, eligible Indian Tribes, or the EPA, depending on the entity with jurisdiction and the EPA’s approval in a particular area. For States, such plans, once approved by the EPA, are referred to as State implementation plans or SIPs. Similarly, for eligible Indian Tribes these plans, once approved, are called Tribal implementation plans or TIPs.
Section 110 of the Clean Air Act, 42 U.S.C. §7410, requires States to adopt Federally approved control strategies to minimize air pollution. The resulting body of regulations is known as a SIP. SIPs generally establish limits or work practice standards to minimize emissions of the criteria air pollutants or their precursors. The criteria air pollutants include sulfur dioxide, particulate matter, nitrogen oxides, lead, carbon monoxide, and ozone. The EPA has established standards, NAAQS, for these pollutants. SIPs also include special control strategies for nonattainment areas -- areas that are not meeting the NAAQS. These control strategies often include measures such as vehicle inspection and maintenance programs, lower gasoline vapor pressures, gas pump vapor recovery, and other reasonably available control technologies (RACT). SIPs also include preconstruction permit requirements for projects that may result in emission increases.
Sections 110 and 301(d) of the Clean Air Act and the EPA’s implementing regulation at 40 CFR part 49 provide for Tribal implementation of various Clean Air Act programs including TIPs. Eligible Indian Tribes can choose to implement certain Clean Air Act programs by developing and adopting a TIP and submitting the TIP to the EPA for approval.