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EPA Determinations that New or Revised Water Quality Standards are Necessary

EPA has issued the following determinations under Clean Water Act section 303(c)(4)(B) that new or revised standards are necessary.

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National Toxics Rule

National Toxics Rule Promulgation and Withdrawals (promulgated in 1992, proposed in 1991).


Colville Confederated Tribes





Mississippi River segment near St. Louis
Mississippi River segments upstream and downstream of St. Louis
141 Water Body Segments in the State of Missouri


Federal Water Quality Standards for Indian Country

On January 18, 2001, the EPA Administrator, Carol Browner, signed a proposed rule to promulgate federal water quality standards for certain waters in Indian country that did not have applicable Clean Water Act standards. However, after signature EPA never published it in the Federal Register or requested public comment upon it. The proposal was based on the Administrator’s determination that such standards are necessary.

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