This paper presents the results of resistivity-IP imaging for two sites where Zn-Pb post-mining wastes are deposited. At the first one the historical washed waste and tailings were stored directly on the soil. In the second location tailings were used as filling material for the reclaimed sinkhole. For both of the investigated locations differences between the geoelectrical properties of the waste and surrounding sediments were noticed. The tailings are characterized by lower resistivity and increased normalized chargeability in comparison to the natural sediments. These features are caused by the presence of the Fe and Pb sulphides and clay minerals. Washed waste exhibited raised resistivity, but it was lower than values observed for uncontaminated sediments. This kind of waste does not show increased chargeability.