An environmental chemistry service-learning project was implemented by Greenville University in coordination with the local county health department to test the quality of well water for residents in a five-county region of southern Illinois. Well owners attended a student run well water testing "kickoff meeting", received testing kits, collected their water samples as instructed, and returned the kits to the health department on a predetermined date. Student investigators analyzed the water samples for a range of contaminants, including the concentrations of eight different metals (including lead and arsenic), nitrate ion, and the presence of coliform and "Escherichia coli" bacteria. Values for pH and water hardness were also determined. The results were communicated to well owners through well water testing reports and at an "interpretation meeting", where students met with the well owners to help them understand and interpret their results. To date, over 130 wells have been tested. The project provided student investigators positive service-learning experiences while delivering many southern Illinois well owners important water quality information.