Adventures in designating the Mahomet Aquifer of Illinois as a sole source aquifer

The Sole Source Aquifer (SSA) Program was an original part of the Safe Drinking Water Act of 1974. SSA designation is intended to protect critical groundwater resources for public health and long-term economic development and is designed to protect aquifer quality by adding a USEPA review component to certain federally-funded projects. Some 73 aquifers have been designated as Sole Source Aquifers, but none in almost 20 years. Recent threats to the Mahomet Aquifer in Illinois spurred a coalition of communities to seek ways to protect the aquifer, one of which was to seek designation of the aquifer as an SSA. The Mahomet provides drinking water to an estimated 700,000 people including ~120 communities and thousands of rural residents. SSA designation efforts were initiated when application to USEPA Region V was submitted in December 2012. On a purely technical level, the aquifer clearly falls within the definition of a SSA. However, concerns have been raised regarding possible unintended consequences resulting from designation. A discussion of the designation process and pitfalls, and the importance of public education and input, will be presented. As of November 2013, no decision on designation had been made.