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Guidance on Petitioning for Sole Source Aquifer (SSA) Designation

EPA published the Sole Source Aquifer (SSA) Designation Petitioner Guidance in 1987 to assist interested parties in submitting SSA designation petitions to EPA regional offices.

The guidance provides procedures and criteria for:

  • Proposing aquifer boundaries
  • Determining whether an aquifer is the sole or principal source of drinking water
  • Evaluating alternative sources of drinking water

Read the sole source aquifer designation petitioner guidance.

Any individual, corporation, company, association, partnership, state, municipality, or federal agency may petition EPA for SSA designation. A petitioner is responsible for providing EPA with sufficent data and information. EPA may also initiate SSA designations.

If the petition is approved, EPA publishes a Federal Register notice that:

  • Announces EPA's decision to designate the aquifer as an SSA
  • Summarizes the basis for the decision

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