The U.S. Supreme Court held, 6-3, that the "functional equivalent of a direct discharge" of pollutants requires a CWA permit, and remanded for consideration of whether a discharge of pollutants into groundwater that later discharged into the Pacific Ocean meets this standard.

The U.S. Supreme Court affirmed in part and vacated in part the Montana high court's ruling in a lawsuit concerning cleanup actions across a 300-square-mile Superfund site in Butte.

The D.C. Circuit affirmed dismissal of an environmental group's request to compel EPA to produce guidelines for commercial or industrial solid waste incinerators (CISWI) and other categories of solid waste incinerators (OSWI).