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Water Quality Standards Regulations: Assiniboine and Sioux Tribes of the Fort Peck Indian Reservation

Presented are water quality standards in effect for Clean Water Act (CWA) purposes.

EPA is posting these standards as a convenience to users and has made a reasonable effort to assure their accuracy. Also, for each document listed under "Tribe Standards in Effect for CWA Purposes", EPA has made a reasonable effort to identify parts of the standards that are disapproved or are otherwise not in effect for CWA purposes.

Authority to Administer Standards Program

These tribes were granted treatment in a manner similar to a state (TAS) on August 29, 1996.  

Tribe Standards in Effect for CWA Purposes

The Tribes’ initial water quality standards were approved on April 25, 2000. The Tribes' water quality standards are applicable to "waters of the Tribe". In some limited instances, the definition adopted by the Assiniboine and Sioux Tribes for "waters of the Tribe" as part of their water quality standards may result in water quality standards that are more comprehensive than required under section 303(c) of the Clean Water Act and the implementing federal regulations. EPA has included the Assiniboine and Sioux Tribes' water quality standards in their entirety here for context and as supplementary information for the reader.  

Federally Proposed or Promulgated Standards

At this time, there are no federally proposed or promulgated standards applicable to this tribe.

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