Consecutive geoelectric measurements reveal the downward movement of an oxidation zone.

An investigation program for monitoring pyrite oxidation on a conveyer bridge dump used geoelectric measurement for monitoring the progress of pyrite oxidation within the dump. The results of the geoelectric measurement show that low soil-pH and high pore water conductivity correlate with low soil resistivity values. The soil resistivity values are dominated by high pore water conductivity. The influence of changes in water saturation on resistivity was comparably low. An increase in pyrite oxidation was observed in areas with high porosity due to low dump density. Consecutive geoelectric measurements revealed locally differentiated downward movement of an oxidation zone caused by dump heterogeneity.