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Sole Source Aquifer Project Review

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Project review coordination

Proposed projects for federal financial assistance within the project review area of a designated SSA which have the potential to contaminate the aquifer are subject to EPA review.  Projects are not subject to EPA review if they either:

  • Lie outside the SSA project review area
  • Do not receive federal financial assistance

EPA may negotiate agreements, sometimes called Memoranda of Understanding (MOUs), with federal agencies that offer financial assistance for projects.  The MOUs list criteria and project types to help the financing agency identify projects that may need SSA review.   

EPA has established MOUs with the:

  • U.S. Federal Highway Administration
  • U.S. Department of Housing and Urban Development
  • U.S. Department of Agriculture - Rural Development

Project review steps

Once a project is identified, the financing agency sends project information to the appropriate EPA regional office for review and evaluation. If the evaluation indicates that the project does not have significant potential to contaminate the SSA, EPA notifies the financing agency that the project may continue as planned.

If there is insufficient information to evaluate the project, EPA will request further information. 

If the project has potential to contaminate the aquifer, EPA will begin negotiations to modify the project. If negotiations are not successful, federal funding can be denied.


Examples of projects EPA reviews 

Examples of types of projects, and their funding agencies, that EPA has reviewed include:

  • Major highway improvement projects: U.S. Department of Transportation (USDOT) Federal Highway Administration (FTA)
  • New transit centers and park-and-ride lots: USDOT FTA
  • Public water supply improvements and wastewater treatment facilities: U.S. Department of Agriculture (USDA) Rural Development Authority (RDA)
  • Housing subdivisions and other building construction projects not served by public water, sewer and storm water drainage systems: U.S. Department of Housing and Urban Development (USHUD) and USDA RDA
  • Light rail projects: USDOT FTA
  • Agricultural projects that involve management of animal waste: USDA RDA
  • Projects funded through Community Development Block Grants: USHUD

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Projects excluded from review:

Projects excluded from review under the SSA program include those that are funded:

  • Entirely by state, local or private entities
  • Solely with federal funds for federal agencies

The SSA program applies to federal assistance, but not to direct federal actions. Work performed for or by the federal government is not included among the projects EPA reviews. This includes work on military bases and other federal facilities.

Projects undertaken within a designated SSA area without federal funds must still comply with all federal, state and local water quality requirements.

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Opportunities for public awareness and participation:

The public may participate in the SSA designation decision process by providing written comments to EPA during a formal comment period. If there is significant interest or a request, EPA may hold a public meeting or hearing.

EPA takes interest in public comment on potential SSA designations.  The Safe Drinking Water Act requires EPA to make decisions on SSA designation based on its analysis of the scientific and economic data presented. 


Limitations of the SSA program

Sole source aquifer designation provides limited protection of ground water resources which serve as drinking water supplies. The SSA program is not a comprehensive ground water protection program. Protection of ground water resources can best be achieved through an integrated and coordinated combination of federal, state, and local efforts.

SSAs are determined to be a "sole or principal" source of drinking water.  This does not, however, imply that they are more or less valuable or vulnerable to contamination than other aquifers which EPA has not designated as SSAs.  Many valuable and sensitive aquifers are not designated because no petition was filed or because the aquifier did not qualify as an SSA.

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