{"data":{"id":"us/40-cfr-141.904","jurisdiction":"us","citation":"40 CFR 141.904","heading":"Reporting and recordkeeping requirements.","body":"Systems required to sample must report to the State according to the timeframes and provisions of § 141.31 and retain records according to the provisions in § 141.33.\n(a) Systems must report the information from initial monitoring specified in the following table:\nTable 1 to Paragraph (a)—Data To Report From Initial Monitoring\nIf you are a . . . You must report . . .\nSystem monitoring for regulated PFAS under the requirements of § 141.902(b)(1) on a quarterly basis 1. All sample results, including the locations, number of samples taken at each location, dates, and concentrations reported. 2. Whether a trigger level, defined in § 141.902(a)(5), was met or exceeded in any samples.\nSystem monitoring for regulated PFAS under the requirements of § 141.902(b)(1) less frequently than quarterly 1. All sample results, including the locations, number of samples taken at each location, dates, and concentrations reported. 2. Whether a trigger level, defined in § 141.902(a)(5), was met or exceeded in any samples.\n(b) Systems must report the information collected during the compliance monitoring period specified in the following table:\nTable 2 to Paragraph (b)—Data To Report From Compliance Monitoring\nIf you are a . . . You must report . . .\nSystem monitoring for regulated PFAS under the requirements of § 141.902(b)(2) on a quarterly basis 1. All sample results, including the locations, number of samples taken at each location, dates, and concentrations during the previous quarter. 2. The running annual average at each sampling point of all compliance samples. 3. Whether a trigger level, defined in § 141.902(a)(5), was met or exceeded in any samples. 4. Whether an MCL for a regulated PFAS in § 141.61(c) was met or exceeded in any samples. 5. Whether, based on § 141.903, an MCL was violated.\nSystem monitoring for regulated PFAS under the requirements of § 141.902(b)(2) less frequently than quarterly 1. All sample results, including the locations, number of samples taken at each location, dates, and concentrations during the previous monitoring period. 2. Whether a trigger level, defined in § 141.902(a)(5), was met or exceeded in any samples. 3. Whether an MCL for a regulated PFAS in § 141.61(c) was met or exceeded in any samples. 4. Whether, based on § 141.903, an MCL was violated (e.g., the results from a single sample are more than 4 times the MCL).","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER D—WATER PROGRAMS","PART 141—NATIONAL PRIMARY DRINKING WATER REGULATIONS","Subpart Z—Control of Per- and Polyfluoroalkyl Substances (PFAS)"],"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":"a604a94100c56c02b597b12fe6a6f1abd4fbea8e1294dce8da4c307d2ba4be72","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-141.903","next":"us/40-cfr-141.905"},"notice":"GroundRules: Original legal text. Not legal advice."}