Qualidade da água em região alterada pela mineração de carvão na microbacia do rio Fiorita (Siderópolis, Estado de Santa Catarina, Brasil)

Abstract

Coal mining is an important economical activity in the south of Santa Catarina, Brazil. The Fiorita River basin (municipality of Siderópolis) was heavily mined out and nowadays several places with mining spoils and sterile soil, as well as acid lakes, can be found in its area. This study aimed to carry out an environmental diagnosis on the water bodies quality in that region. Graphic and cluster analysis suggested that the Fiorita River basin was compartmented. It seemed that there was a deterioration gradient in water quality toward the lower portion of the basin, with pH decrease and a rise in values of total acidity, electric conductivity, Eh, total solids contents, sulphate, aluminium, calcium, iron II and totals, manganese and magnesium. Data suggested concentration effect, mainly of metals. As a first approach, according to Conama 20 (1986), water quality of Fiorita River basin is low and restricted to use. Subsidies to environmental recuperation of the area are also contemplated.