{"data":{"id":"us/40-cfr-141.604","jurisdiction":"us","citation":"40 CFR 141.604","heading":"Very small system waivers.","body":"(a) If you serve fewer than 500 people and you have taken TTHM and HAA5 samples under subpart L of this part, you are not required to comply with this subpart unless the State notifies you that you must conduct standard monitoring under § 141.601 or a system specific study under § 141.602.\n(b) If you have not taken TTHM and HAA5 samples under subpart L of this part or if the State notifies you that you must comply with this subpart, you must conduct standard monitoring under § 141.601 or a system specific study under § 141.602.","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER D—WATER PROGRAMS","PART 141—NATIONAL PRIMARY DRINKING WATER REGULATIONS","Subpart U—Initial Distribution System Evaluations"],"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":"575b78b48cdca7452870daf4079fd2b41117ef1767b432028ce1c16392a3c8fa","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-141.603","next":"us/40-cfr-141.605"},"notice":"GroundRules: Original legal text. Not legal advice."}