Aplicação de métodos geofísicos para identificar áreas contaminadas por resíduos de um curtume

Abstract

The main problem on environmental investigations is the determination of contaminated extension area. This work exhibit some results obtained with the geophysical methods applied to locate potentially contaminated areas with tanning residues. The area is located near to the city of Várzea Grande, Mato Grosso State. It was now interdicted and disabled for the residues deposition. The data were acquired from electrical profiles, with inline dipole-dipole array and 4 m spacing electrodes, allowing 5 investigation depths. The data of apparent electric conductivity were acquired in 2 dipole modes (horizontal and vertical coplanar) with intercoil spacing of 10 meters. The 200 MHz unshielded antennas were used to collect GPR data. The station interval to each 0.25 meters and 128 stacks. The areas were classified in Contaminated Area - AC - (σa > 40 mS/m, ρ < 30 ohm.m and high attenuation of GPR), Suspect Area - AS - (σa of 20 to 40 mS/m, ρ of 30 to 50 ohm.m) and Without Contaminated - AN - (σa < 20 mS/m, ρ > 50 ohm.m and low attenuation of GPR). The integrated results allow the contamination maps elaboration, indicating a potentially contaminated area with a preferential NW-SE flux. The geophysics and geological information showed an efficient preliminary analysis in the identification of contaminated areas. © 2006 Sociedade Brasileira de Geofísica Contamination, industrial residues, tanning, EM-34, resistivity, GPR, Várzea Grande.