Whether a defendant's addition of pollutants to a navigable water from a point source via groundwater conduits may ever violate the Clean Water Act's prohibition on the unpermitted 'discharge of a pollutant'

QUESTION PRESENTED Absent authorization by permit, the Clean Water Act prohibits the “discharge of a pollutant,” defined as “any addition of any pollutant to navigable waters from any point source.” 33 U.S.C. § 1362(12)(A). In County of Maui v. Hawaii Wildlife Fund, No. 18-260 (U.S. filed Aug. 27, 2018) (Maui), the Court granted certiorari to determine “whether the [Clean Water Act] requires a permit when pollutants originate from a point source but are conveyed to navigable waters by a nonpoint source, such as groundwater.” In this case, after a trial, the district court found that Respondent Tennessee Valley Authority is violating the Clean Water Act by adding toxic coal ash pollutants to the Cumberland River via a network of pipe-like conduits in the bedrock through which groundwater flows. The Sixth Circuit reversed, holding as a matter of law that the Clean Water Act never applies to any pollutant that travels from a point source through groundwater before polluting navigable waters. The question presented is: Whether a defendant’s addition of pollutants to a navigable water from a point source via groundwater conduits may ever violate the Clean Water Act’s prohibition on the unpermitted “discharge of a pollutant.”