Abstract:
<p align="justify"> This paper presents a comparative hydrogeochemical characterization on the predominant ions of the underground water that flow the Cocal vein, in the Mina 3 (Companhia Nitroquímica Brasileira), Fluorine Distritic of Santa Catarina, Morro da Fumaça Co., Santa Catarina, Brazil. Four samples were selected: P1 – underground water to 300 m of depth; P2 –underground water to 150 m of depth; P3 – water of the dam of reject; P4 – treated water of provisioning of Companhia Catarinense de Águas e Saneamento (CASAN). In the water sample collected in the selected sources, quantitative determinations of physical-chemical parameters (pH and electric conductivity) and of cations (Al, Ca, Cl, Li, Mg, Mn, K, Si, Na, and Zn) and anions (sulfate, chloride, bicarbonate, and fluorine) were performed. The results obtained revealed that most of the analyzed ions are related to the representatives that originated from rocks that constitute the pools where the studied water flow. The hydrogeochemical classification was obtained starting from the miliequivalence pattern among the main elements, in the cations and anions form being used the triangular diagram of Piper. The underground water of the point 1 presented a hydrogeochemical characterization compatible with is geological environment occurrence and being perceptible the characterization of an interrelation among the rock and the water that circulate within and they also presented an amount of larger ions than the water of the point 2, in since it flow through a mineralized pool. The underground water of the point 2 presented good potable conditions, with some restrictions. In the water of the point 3 there is a larger ions concentration by due to the washing of the mineral, that allows a larger solubilization of the elements, and the time of permanence of the water in the lake also causes larges concentration. The water collected in P4 point exhibit good water potability parameters and absence of conditions that favor fluorosis. </p>