§ 421.90 Applicability: Description of the metallurgical acid plants subcategory
§ 421.91 Specialized definitions
§ 421.92 Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available
§ 421.93 Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable
§ 421.94 Standards of performance for new sources
§ 421.95 Pretreatment standards for existing sources
§ 421.96 Pretreatment standards for new sources