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Evaluating Implementation Issues for Six-Year Review of Drinking Water Standards

EPA considers potential issues or concerns with national primary drinking water regulations gained from EPA's or states’ experience in implementing the regulations as written.

EPA considers a possible revision based on implementation issues to be appropriate if it would present a meaningful opportunity to:
  • Improve the level of public health protection, or
  • Achieve cost savings while maintaining or improving the level of public health protection.
To evaluate potential implementation issues, EPA also considers:
  • The extent to which the issue is national in scope,
  • Whether the change would require a regulatory modification, and
  • The extent to which the problem to be resolved has been clearly defined and specific options to address the problem have been formulated.