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Environmental Programs and Technical Assistance on Tribal Lands

Tribes play a primary role in protecting air on their reservations.

Clean Air Act and Tribal Authority Rule

Tribes have authority to manage air quality on their reservations under the Clean Air Act. Their role is set forth in the Tribal Authority Rule (TAR). TAR sets forth the following:

Tribal Implementation Plans

A tribe with TAS eligibility may develop its own plan for implementing national ambient air quality standards. These plans are called Tribal Implementation Plans (TIP). A TIP must be approved by EPA.  A TIP is legally binding under both tribal and federal law and may be enforced by the tribe, EPA, and the public.  

Besides TIPs, tribes may also implement the Title V permit program, New Source Performance Standards, and National Emission Standards for Hazardous Air Pollutants.

Voluntary Programs

In addition to their obligations under the Clean Air Act, tribes engage in a number of voluntary programs, including:

  • monitoring for visibility and air pollutants (including particulate matter, ozone, ammonia, mercury, etc.);
  • smoke management programs;
  • indoor air quality programs, addressing issues like tobacco smoke and mold;
  • replacing woodstoves with cleaner models;
  • testing homes for radon;
  • reducing greenhouse gas emissions through energy efficiency and renewable energy use;
  • preparing for and building resiliency to the impacts of climate change;
  • reducing diesel emissions.

Technical Assistance and Air Program Resources

EPA’s Office of Air and Radiation (OAR) provides tribes with technical assistance and resources. It does this through both Headquarters and Regional Offices. It also works with Northern Arizona University’s Institute for Tribal Environmental ProfessionalsExit which provides air quality training and technical assistance to tribes. 

OAR is also developing Tribal New Source Review rules. These rules will help EPA address air quality problems in Indian country in cases where a tribe may be unable to do so themselves.