40 CFR 141.531
§ 141.531 What criteria must a State use to determine that a profile is unnecessary?
United States · 40 CFR — Protection of Environment · Status: effective
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- Citation
- 40 CFR 141.531, § 141.531 What criteria must a State use to determine that a profile is unnecessary?, United States, version 1 as recorded 2026-07-09, yourstate.us, https://yourstate.us/provision/182010
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Full text
States may only determine that a system's profile is unnecessary if a system's TTHM and HAA5 levels are below 0.064 mg/L and 0.048 mg/L, respectively. To determine these levels, TTHM and HAA5 samples must be collected after January 1, 1998, during the month with the warmest water temperature, and at the point of maximum residence time in your distribution system. Your State may approve a more representative TTHM and HAA5 data set to determine these levels.
Legislative history
This is a federal regulation, adopted through agency rulemaking under the Administrative Procedure Act — not enacted by a recorded vote of Congress.