EFFLUENT LIMITATIONS GUIDELINES AND STANDARDS: 30 YEARS OF DECISIONS BASED ON CLEAN WATER ACT MANDATED FACTORS

Congress passed the Federal Water Pollution Control Act (1972), also known as the Clean Water Act (CWA), to “restore and maintain the chemical, physical, and biological integrity of the Nation's waters.” (33 U.S.C. 1251(a)). The CWA establishes a comprehensive program for protecting our nation's waters. Among its core provisions, the CWA prohibits the discharge of pollutants from a point source to waters of the U.S. except as authorized by a National Pollutant Discharge Elimination System (NPDES) permit. The CWA also requires EPA to establish national technology-based effluent limitations guidelines and standards (effluent guidelines or ELGs) for different categories of sources, such as industrial, commercial and public sources of waters. Effluent guidelines are implemented when incorporated into an NPDES permit, and can include numeric and narrative limitations, including Best Management Practices, to control the discharge of pollutants from categories of point sources.