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

The support documents for the third Six-Year Review of National Primary Drinking Water Standards contain extensive information including:
  • The protocol for conducting the review,
  • 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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