{"data":{"id":"us/40-cfr-57.401","jurisdiction":"us","citation":"40 CFR 57.401","heading":"General requirements.","body":"Except as provided in subpart E, each NSO shall require the smelter owner to prevent all violations of the NAAQS in the smelter's designated liability area (DLA) through the operation of an approved supplementary control system (SCS).","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER C—AIR PROGRAMS","PART 57—PRIMARY NONFERROUS SMELTER ORDERS","Subpart D—Supplementary Control System Requirements"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-40.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:04Z","sha256":"4d7297ac6131a0ed530cd867348b461f277923e2e5b59def9932f14d595389bf","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-57.305","next":"us/40-cfr-57.402"},"notice":"GroundRules: Original legal text. Not legal advice."}