ASSESSMENT OF THE FINAL DISPOSAL OF SOLID RESIDUES FROM TANNERIE

Abstract

This work aim to study the impacts caused by the disposal of residues from two tanneries localized in the municipalities of Cuiabá and Várzea Grande in Mato Grosso State, particularly on groundwater. In one of the tanneries (tannery 1), the final residue disposal was done over an impermeable blanket inside a trench covered with amianthus tiles while in the other (tannery 2) the residues were disposed directly on the soil covered with the impermeable blanket. To achieve this objective, physical chemical and chemical properties which could indicate alteration of groundwater quality in the areas of final disposal of tannery residues were determined. Groundwater samples were collected in monitoring wells built in those areas. The analysis of the physical chemical and chemical variables allowed the following conclusions: i) the residues disposal in tannery 1 contributed to increase chromium concentrations, pH; electrical conductivity and also total dissolved solids; ii) the residues disposal in tannery 2, contributed to increase the concentrations of chloride, electrical conductivity and as a consequence total dissolved solids. Although the two tanneries are at work for different times (tannery 1 from 2000 and tannery 2 from 1986) using different residues disposal procedures, no significant difference were observed in the alteration of groundwater quality in the two sites.