Dioxin/Organochlorine Center v. Environmental Protection Agency

In the 1980s, the Environmental Protection Agency (EPA) (defendant) discovered high levels of tetrachlorodibenzo-p-dioxin (TCDD), a toxic pollutant, in fish from the Columbia River basin. Studies confirmed that a significant source of the TCDD found in the fish was the pulp and paper mills (the mills) (plaintiff) upstream from the fish. The EPA determined that the concentration of TCDD in the water exceeded the permissible level of 0.013 parts per quadrillion (ppq) set by the states regulating the water quality in the Columbia River Basin. The EPA further determined that the activity of the mills was a major reason for the high TCDD concentration. In addition, the Columbia River Basin states determined that the levels of TCDD discharged into the river violated the states’ water quality standards, and designated the Columbia River as water quality limited, pursuant to the Clean Water Act (CWA). As a result of these findings, as well as the states’ designations, the EPA issued a total maximum daily load (TMDL) for TCDD discharge into the Columbia River. A TDML limits the total amount of a pollutant that can be discharged into a body of water from all sources. The EPA interpreted the act as giving it authority to establish TMDLs even without first establishing technology-based effluent limitations for TCDD. The mills challenged the TDML, arguing that the CWA requires the EPA to first establish less burdensome technology-based limitations before establishing a TDML.