Geochemical composition of water at the Syri i Kalter springs and in the Bistrica river (south Albania)

Analyses of waters from Syri i Kalter (Blue Eye) spring and from the Bistrica river show relatively high concentrations of calcium, sulphate and alkalinity, with a minor magnesium content and low concentrations of alkali-ions and chloride. From the geology of the area surrounding the spring, it can be acknowledged that minerals within the aquifer are represented mainly by calcite, dolomite and gypsum (or anhydrite). Calculations of minerals equilibrium display that all samples are undersaturated with respect to gypsum, and supersaturated with respect to calcite. As to saturation with respect to dolomite, samples from Syri i Kalter spring result close to equilibrium. Dissolution and precipitation reactions of these minerals provide an adequate description of the geochemical composition of the water at the spring and in the different parts of the Bistrica river.