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Support Documents for EPA’s Second Review of Existing Drinking Water Standards

The support documents for the second Six-Year Review of existing National Primary Drinking Water Standards contain extensive information including:
  • the protocol for conducting the review,
  • chemical contaminant health effects, 
  • availability of improved laboratory analytical methods, 
  • occurrence of regulated contaminants in source water and public water systems,
  • availability of improved water treatment processes, and
  • consideration of other regulatory revisions.
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