Use of the geophysical method EM 34-3 in the study of groundwater contamination by coal waste and ashes

The main objective of this paper is to evaluate the efficiency of the geophysical technique EM – 34 – 3 in the study of the groundwater contamination by residues from coal processing. It was applied, in the coal waste and ashes disposal site – CH 20, located in the municipal district of Charqueadas, the electromagnetic geophysical method EM – 34 – 3, which measures the electric conductivity of the medium in subsurface. It was noticed that the highest anomalous electrical conductivity values and ions content were placed inside the disposal site with the most significant contamination situated in the phreatic aquifer. Besides, it was verified an incipient pollution plume in the direction of groundwater flow (to SW). The methodology presented good results in the delimitation of the polluted area, supplying a guiding character for posterior sampling campaigns of contamination groundwater degree and indicating the concentrations of the pollutant elements in subsurface.