American Paper Institute, Inc. v. United States Environmental Protection Agency

The Clean Water Act (CWA) prohibited the discharge of pollutants from any point source into the nation’s waters unless the discharge was permitted under the National Pollutant Discharge Elimination System (NPDES). The Environmental Protection Agency (EPA) (defendant) authorized 40 states to administer the NPDES program in those states and administered the program for remaining states. Under § 301 of the CWA, NPDES permits were required to contain limitations that sufficiently assured that the receiving waterway satisfied water-quality standards. Water-quality standards were principally set by states. The standards could be stated in narrative form, e.g., “no toxic pollutants in toxic amounts,” or as numerical limitations, e.g., “no more than .05 milligrams of chromium per liter.” NPDES-permit writers encountered significant difficulties in translating narrative water-quality standards into effluent limitations for specified pollutants and sometimes simply ignored the narrative criteria. As a result, the EPA promulgated an interpretive rule that required permit writers to use one of three methods to translate narrative criteria into precise pollutant-specific numerical effluent limitations in NPDES permits. A group of corporations, a city, and utilities (collectively, the challengers) (plaintiffs) petitioned the court for review of the EPA’s rule, arguing in essence that the rule contravened the division of responsibility between states and the EPA to achieve clean water.