![[logo] US EPA](https://webarchive.library.unt.edu/eot2008/20090511013633im_/http://www.epa.gov/epafiles/images/logo_epaseal.gif){kind=logo}
Sole Source Aquifers
National Information
Mid-Atlantic Sole Source Aquifers
Map of Mid-Atlantic Sole Source Aquifers
The Sole Source Aquifer (SSA) Program, which is authorized by Section 1424(e) of the Safe Drinking Water Act, allows communities to petition the US Environmental Protection Agency for protection when a community is dependent on a single source of drinking water and there is no possibility of a replacement water supply to be found. EPA regional offices review the petitions and, if merited, the Regional Administrator will designate an area as a Sole Source Aquifer. The SSA program provides federal overview of federally-funded projects within the designated area. Projects and land uses which are not federally-funded are not subject to federal overview.
EPA defines a sole or principal source aquifer as one which supplies at least 50% of the drinking water consumed in the area overlying the aquifer. EPA guidelines also stipulate that these areas can have no alternative drinking water source(s) which would physically, legally, and economically supply all those who depend upon the aquifer for drinking water. Usage data and other technical and administrative information are required for assessing designation criteria. In general, the designation decision process takes a minimum of 6 months from the time that the petitioner submits a completed petition to EPA.
SSA designations increase the public's awareness on the nature and value of local ground water resources by demonstrating the link between an aquifer and a community's drinking water supply. Often the realization that an area's drinking water originates from a vulnerable underground supply can lead to an increased willingness to protect it. The public also has an opportunity to participate in the SSA designation process by providing written comments to EPA or by participating in an EPA sponsored public hearing prior to the designation decision.
Although designation aquifers have been determined to be the "sole or principal" source of drinking water for an area, this does not imply that they are more or less valuable or vulnerable to contamination than other aquifers which have not been designated by EPA. Many valuable and sensitive aquifers have not been designated simply because nobody has petitioned EPA for such status or because they did not qualify for designation due to drinking water consumption patterns over the entire aquifer area. Furthermore, ground water value and vulnerability can vary considerably both between and within designated aquifers.
