Study on subsurface contamination flow path distribution using Electrical Resistivity Imaging (ERI) technique at waste disposal site: Taiping, Malaysia

Abstract

This study focuses on the effect of the leachate to the surface and groundwater pollution at Taiping landfill site. The site was previously used for tin ore and other alluvial ore minerals mining. Consequently, the soil stratification of the area was extensively disturbed by tin mining activities in the past. Geologically, the area consists of mainly recent alluvium of Quaternary in aged. Electrical Resistivity Imaging (ERI) technique is used in mapping the pollution distribution in the form of leachate plumes. Results show that groundwater at depth of 5 to 15m was contaminated by the leachate from the dumping site as indicated by resistivity values less than 10 Ohm-m in the pseudosections. In addition, leachate plumes appeared to have seeped to about 30-50m in depth. Resistivity of the backfill surface covering material is found greater than 100 Ohm-m. The study has led to the delineation of the groundwater contamination zones within the study area as well as the distribution of the pollutant in the soil strata at depth less than 30m. This implies that the ERI technique is an effective tool in detecting contaminated groundwater zones or layers.