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Drinking Water Requirements for States and Public Water Systems

Memo Clarifying Requirements and State Reporting Guidance to Transition to the Revised Total Coliform Rule

This memorandum provides guidance to primacy agencies with enforcement responsibility under the Safe Drinking Water Act (SDWA) concerning the requirements to transition public water systems (PWSs) from the Total Coliform Rule (TCR) to the Revised Total Coliform Rule (RTCR). This transition started April 1, 2016 or on an earlier State effective date, whichever comes first.

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