Abstract: Koçpınar springs emerge on strike - slip Hasandağı Fault Set (HFS) along Tuzgölü Fault Zone (TFZ) which extends in northwest - southeast direction. The exposed rocks, most of which are volcanic, exhibit different hydrogeologic properties in the studyarea. As meteoric waters rise to the surface ion concentration occurs through water - gas - rock interaction. Marbles of Paleozoicage form the aquifer of the springs. The CO2 gas content of the springwaters is high enough to produce dry ice (solidified carbon dioxide). The CO2 gas is also responsible for the calcite dissolution in the marbles forming carbonic acid through reactions with water. On the basis of ion concentrations, two hydrochemical fades have been identified as Ca - Mg - HCO3 andNa - HCO3 springwaters meet the drinking water standards. Three protection zones are suggested against the external effects in the spring area.