Investigation of thermal water disposal impact in the Caiuazinho River, Presidente Epitácio – SP

Abstract

The thermal water of the Guarani Aquifer located in the municipality of Presidente Epitacio / SP, previously used for recreational purposes, is now ruled out for  Caiuazinho River, tributary of the Paraná River. The water temperature measured at the wellhead is 70 ° C and physicochemical characteristics different from those observed in Caiuazinho River. Considering the uncertainties of the influence of the hot water discharge quality of the river, this work aimed to use stable isotopes and measurement of water physical-chemical parameters, to evaluate the influence of thermal water in the Caiuá Aquifer and surface water in the area of interest. To achieve the proposed objectives were collected 32 samples of surface water for isotopic analysis and performed the measurement of physical-chemical parameters in 48 different points of Caiuazinho River at 3 different depths (totalizing 224 measurments). The isotopic results together with the measurement of physical and chemical parameters indicate that the flow of thermal water discarded, i.e. 34.5 m³ / h, not promote significant changes in the river's characteristics.