Water Quality Standards; Establishment of Numeric Criteria for Priority Toxic Pollutants; States' ComplianceRevision of Polychlorinated Biphenyls (PCBs) Criteria

The Clean Water Act (CWA) requires States to adopt numeric criteria for priority toxic pollutants for which EPA has published criteria guidance if the discharge or presence of such pollutants could reasonably be expected to interfere with the designated uses of the State's waters. In 1992, EPA promulgated the National Toxics Rule (NTR) establishing numeric water quality criteria for toxic pollutants in fourteen States and jurisdictions to protect human health and aquatic life. These States and jurisdictions had not adopted sufficient chemical-specific, numeric criteria for toxic pollutants necessary to comply with the Clean Water Act. Among the criteria promulgated in the NTR were human health and aquatic life water quality criteria for polychlorinated biphenyls (PCBs). Today, EPA is issuing revisions to the human health water quality criteria for PCBs in the NTR, based on the Agency's reassessment of the cancer potency of PCBs. The revised criteria will apply in: Alaska, District of Columbia, Kansas, Michigan, Nevada, New Jersey, Puerto Rico, Rhode Island, Vermont and Washington.