Water Quality Standards; Establishment of Numeric Criteria for Priority Toxic Pollutants; States' ComplianceRevision of Metals Criteria

EPA is promulgating new aquatic life metals criteria for nine States, Puerto Rico, and the District of Columbia, that are subject to EPA's 1992 National Toxics Rule (``NTR''). These new metals criteria reflect EPA's current policy for setting water quality criteria for metals. This interim final rule establishes metals criteria that are protective of aquatic life and approximate, better than the 1992 criteria, the biologically available fraction of water borne metals to aquatic organisms. Use of the new metals criteria will allow permitting authorities in the nine States, Puerto Rico and the District of Columbia, to establish effluent limitations based on the new metals criteria rather than the 1992 criteria which EPA now considers to be more stringent than may be necessary to protect designated uses for aquatic life. The interim final rule will be in effect while EPA considers public comments and develops a final rule. This rule terminates the Administrative Stay published elsewhere in this issue of the Federal Register.