{"data":{"id":"us/40-cfr-142.304","jurisdiction":"us","citation":"40 CFR 142.304","heading":"For which of the regulatory requirements is a small system variance available?","body":"(a) A small system variance is not available under this subpart for a national primary drinking water regulation for a microbial contaminant (including a bacterium, virus, or other organism) or an indicator or treatment technique for a microbial contaminant.\n(b) A small system variance under this subpart is otherwise only available for compliance with a requirement specifying a maximum contaminant level or treatment technique for a contaminant with respect to which;\n(1) a national primary drinking water regulation was promulgated on or after January 1, 1986; and\n(2) the Administrator has published a small system variance technology pursuant to Section 1412(b)(15) of the Act.\nNote to paragraph (b)(1):\nSmall system variances are not available for public water systems above the pre-1986 maximum contaminant level even if subsequently revised. If the Agency revises a pre-1986 maximum contaminant level and makes it more stringent, then a variance would be available for that contaminant, but only up to the pre-1986 maximum contaminant level.","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER D—WATER PROGRAMS","PART 142—NATIONAL PRIMARY DRINKING WATER REGULATIONS IMPLEMENTATION","Subpart K—Variances for Small System"],"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":"5733e2c5af262effa6422ab2affe112e74c5c0c76ff3f99b4204101c9cfcff87","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-142.303","next":"us/40-cfr-142.305"},"notice":"GroundRules: Original legal text. Not legal advice."}