Chemical quality of deep groundwaters in Yerba Buena and San Miguel de Tucumán cities

GARCIA M.G.; HIDALGO M. DEL V; APELLA M.C.; BLESA M. A

Workshop; Escuela de Ciencia y Tecnología Ambiental; 1998

            San Miguel de Tucumán and Yerba Buena are the largest cities of the province of Tucumán, with 600000 inhabitants. Main water supply is from the Celestino Gelsi dam and from small rivers of the San Javier range. A large number of wells constitute additional important source of drinking water. In this paper, we describe a study of the groundwater quality for human consumption and we analyse the reasons for the spatial variability in its ionic composition.   The hydrogeochemistry of the groundwater is presented and aanlyse, thus providing the basic information required to assess eventual pollution problems. In the recharge area, the groundwater is alkaline-earth hydrogencarbonated along its flow, the composition changes to a sodium chlorinated predominance. In the middle of the basin, the water is sodium hydrogenocarbonated and alkaline-earth hydrogenocarbonated.   An important increase in sodium concentration is observed in the San Miguel de Tucumán groundwater, probably associated with the exploitation of tertiary sediments, rich in soluble salts.