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National Pollutant Discharge Elimination System (NPDES)

Guidance Memorandum: Applying the Supreme Court’s County of Maui v. Hawaii Wildlife Fund Decision in the Clean Water Act Section 402 National Pollutant Discharge Elimination System Permit Program

This memorandum provides focused guidance to the regulated community and permitting authorities, including the U.S. Environmental Protection Agency, on applying the recent decision of the United States Supreme Court in County of Maui v. Hawaii Wildlife Fund, 140 S. Ct. 1462 (2020), on a case by case basis, in the Clean Water Act Section 402 National Pollutant Discharge Elimination System (NPDES) permit program.

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