Evaluation of the Influence of Vinasse Diposal on Soil by DC-resistivity Data Analysis

The production of each liter of ethanol generates thirteen liters of a brown liquid waste, known as vinasse, which inappropriate disposal represents one of the biggest problems for the alcohol industry due to its elevated pollutant potential. Its chemical composition and its large available amount turns the vinasse into an alternative nutrients supplier for soils in sugarcane crops. However, this practice has great potential of pollution in both groundwater and superficial water resources, and excessive use of vinasse could change the soil behavior. The need of viable methods of detecting and evaluating such environmental contamination by vinasse has made geophysical methods to be valuable tools, thanks to their non invasive characteristics and low cost investigation. This paper reports the use of the DC-resistivity method for the evaluation of the influence of the disposal of large amounts of vinasse on soil in a storage tank. Four resistivity profiles were carried out across the study area, using the dipole-dipole array with 10m of electrode spacing. The geophysical surveys allowed us to conclude that there are lower resistivity values inside the tank compared to uncontaminated areas, showing that the method is a appropriate tool to map the soil influence caused by vinasse.