SOLE SOURCE AQUIFER (SSA)

An aquifer that is the sole or principal source (50 percent or more) of drinking water for a geographical area, as established under Section 1424(e) of the Safe Drinking Water Act (SDWA). This designation bars the use of federal funds for projects in the Recharge Zone that may lead to a significant hazard to the public health by degrading groundwater quality in the aquifer. Also see Critical Aquifer Protection Area (CAPA).