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  2. Six-Year Review of Drinking Water Standards

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

Related Information

Contaminant Occurrence Data
for Six-Year Review 4

The support documents for the fourth 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.
  • EPA Protocol for the Fourth Review of Existing National Primary Drinking Water Regulations (pdf) (1.01 MB, February 2024, EPA-815-R-24-018)
  • The Data Management and Quality Assurance/Quality Control Process for the Fourth Six-Year Review Information Collection Request Dataset (pdf) (2.68 MB, February 2024, EPA-815-R-24-017)  
  • Chemical Contaminant Summaries for the Fourth Six-Year Review of Existing National Primary Drinking Water Regulations (pdf) (880.48 KB, February 2024, EPA-815-S-24-002)
  • Analytical Feasibility Support Document for the Fourth Six-Year Review of Existing National Primary Drinking Water Regulations: Chemical Phase Rules and Radionuclides Rules (pdf) (2.67 MB, February 2024, EPA-815-R-24-015)
  • Analysis of Occurrence Data from the Fourth Six-Year Review of Existing National Primary Drinking Water Regulations: Chemical Phase Rules and Radionuclides Rules (pdf) (4.09 MB, February 2024, EPA-815-R-24-014)
  • Occurrence Analysis for Potential Source Waters for the Fourth Six-Year Review of National Primary Drinking Water Regulations (pdf) (15.18 MB, February 2024, EPA 815-R-24-019)
  • Consideration of Other Regulatory Revisions in Support of the Fourth Six-Year Review of the National Primary Drinking Water Regulations (pdf) (540.07 KB, February 2024, EPA-815-R-24-016)
  • Support Document for the Fourth Six-Year Review of Drinking Water Regulations for Acrylamide and Epichlorohydrin (pdf) (637.58 KB, February 2024, EPA-815-R-24-023)
  • Review of Fluoride Occurrence for the Fourth Six-Year Review (pdf) (495.77 KB, February 2024, EPA-815-R-24-021)
  • Six-Year Review 4 Technical Support Document for Microbial Contaminant Regulations (pdf) (2.87 MB, July 2024, EPA 815-R-24-022)

  • Results of the Health Effects Assessment for the Fourth Six-Year Review of Existing Chemical and Radionuclide National Primary Drinking Water Standards (pdf) (3.91 MB, February 2024, EPA-815-R-24-020)

Six-Year Review of Drinking Water Standards

  • Statutory Requirements
  • Learn About Six-Year Review Elements
  • Six-Year Review 4
  • Six-Year Review 3
  • Six-Year Review 2
  • Six-Year Review 1
Contact Us About the Six Year Review of Drinking Water Standards
Contact Us About the Six Year Review of Drinking Water Standards to ask a question, provide feedback, or report a problem.
Last updated on July 22, 2024
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