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Tribal Assumption of Federal Laws - Treatment as a State (TAS)

Several federal environmental laws authorize EPA to treat eligible federally recognized Indian tribes in a similar manner as a state (TAS) for implementing and managing certain environmental programs. The Clean Air Act (CAA), Clean Water Act (CWA), and Safe Drinking Water Act (SDWA) expressly provide the authority for Indian tribes to play essentially the same role in Indian country that states do within state lands.

The Toxic Substances Control Act (TSCA) and the Emergency Planning and Community Right to Know Act (EPCRA) are silent on the role of tribes. EPA has interpreted these acts to authorize tribal participation.

Though separate from TAS, certain other federal laws provide opportunities for tribal participation. Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) Section 126(a) states that tribes shall be given “substantially” the same treatment as a state, which EPA has interpreted to allow tribes to enter cooperative agreements and receive financial assistance under the statute. Similarly, Section 23 of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) authorizes EPA to enter into cooperative agreements with tribes for specific purposes under the Act.

The basic requirements for applying for TAS are that the tribe must:

  • be federally recognized,
  • have a governing body carrying out substantial governmental duties and powers,
  • have appropriate authority, and 
  • be capable of carrying out the functions of the program.

The Clean Air Act (CAA)

The Clean Water Act (CWA)

The Safe Drinking Water Act (SDWA)

The Toxic Substance Control Act (TSCA)