Environmental Defense Fund v. Environmental Protection Agency

Polychlorinated biphenyls (PCBs) were a group of toxic chemicals used in many industrial processes, most often in electrical devices to aid in the storage of electrical charge without creating a fire hazard. Beginning in the mid-1960s, the presence of leaked PCBs in the environment and the harm PCBs caused to living organisms began to be known. In the early 1970s, manufacturers began to take steps to reduce the dangers presented by PCBs by moving from more chlorinated PCBs to less chlorinated PCBs. Section 307 of the Clean Water Act (CWA) enunciated the considerations and procedures that the Environmental Protection Agency (EPA) (defendant) was required to use in arriving at standards for toxic chemicals, including that the standard be set at a level that provided an ample margin of safety. With the passage of the Toxic Substances Control Act of 1976 (TSCA), Congress included a special provision directing the EPA to publish a list of toxic substances within 90 days, propose effluent standards for the listed substances within 180 days after listing, and promulgate final effluent standards within six months after the proposed standards were issued. The TSCA specifically addressed PCBs, providing for a gradual phasing out of PCBs over a two-and-a-half-year period, with limited exemptions. Pursuant to this authority, the EPA issued final standards prohibiting any PCBs in discharges by manufacturers of electrical equipment. The EPA relied on a variety of studies and types of evidence to determine that no safe level of PCBs could be determined. The evidence included consideration of PCBs’ effects on aquatic organisms, effects on human health, and the special quality of carcinogenicity. Industry members (plaintiffs) argued that the TSCA preempted the EPA’s authority under the CWA to issue effluent standards for PCBs. The industry members further argued that the EPA lacked a reasonable basis for the regulations because of the incomplete scientific knowledge concerning any dangerous effects of less chlorinated PCBs.