HYDROGEOCHEMISTRY CHARACTERIZATION FROM ADAMTINA AQUIFER IN THE URBAN AREA OF BAURU, SP

Abstract

This work characterized the groundwater from Adamantina Aquifer in the urban area of Bauru, São Paulo State. Twenty four sampling points were established in the Adamantina Aquifer, Bauru Aquifer System, analyzing the following parameters: electrical conductivity, temperature, pH, alkalinity, phosphate, sulfate, chlorine, fluorine, nitrate, calcium, sodium, potassium, magnesium, silica, iron and aluminum. The results indicated that the groundwaters in the urban area of Bauru possess pH slightly acid and low conductivity, with the ionic composition presents low cations and anions concentration, being they classified as soft water and calcium-bicarbonated. Natural sources of elements/compounds can be attributed to the dissolution of carbonates during the water/rock interaction, controlling pH, alkalinity, electrical conductivity and hydrolysis of other mineral constituents of sedimentary rocks from Adamantina Formation, with the exception of quartz. High concentrations of N-NO3-found in some public supply wells in urban Bauru originated due to sewage. Keywords: Quality of groundwater, water/rock interactions, anthropogenic sources, Adamantina Aquifer.