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Drinking Water Requirements for States and Public Water Systems

Compliance Determination for Inactivation Requirements of the National Primary Drinking Water Regulations when a Public Water Systems Uses Dichlor and Trichlor for Primary Disinfection

This memorandum has been developed to assist SDWA primacy agencies (EPA Regions, states and territories) when considering inactivation/disinfection compliance requirements for those water systems that choose to use Dichloroisocyanuric acid (Dichlor) or Trichloroisocyanuric acid (Trichlor) for primary disinfection.

View other Public Water System Supervision Program Water Supply Guidance.

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Compliance Determination for Inactivation Requirements of the National Primary Drinking Water Regulations when a Public Water Systems Uses Dichlor and Trichlor for Primary Disinfection (PDF)(2 pp, 469 K, April 18, 2018, WSG 203)