Application of electrical resistivity tomography and hydro-chemical analysis for an integrated environmental assessment

Abstract

Municipal solid waste disposal sites generate groundwater contamination through leachate release to the surrounding environment, causing various harmful and deleterious effects. Thus, an integrated assessment of landfilling impact on the environment via the combination of electrical resistivity tomography (ERT) and hydro-chemical analysis from existing wells was undertaken to ascertain the contamination of both surface and groundwater near the Bizerte landfill site, northeastern Tunisia. The ERT measurement indicated a polluted depth of over 20 m beneath the surface which coincides with marly substratum.Similarly, hydro-chemical analysis showed that continuous leachate generation obviously affected chemical properties of surface and groundwater, especially an increase in heavy metals contents (lead, cadmium and nickel contents). The results also indicated significant microbiological contaminations of the water samples. Nemerow pollution index (WQI) for water classification indicated that all sites had clean water with respect to metal contamination, except for R1 and R2 (surface water), which have WQI values of 2.5 and 2.1, respectively. Based on those results, it is recommended to strictly monitor leachate generation, surface water and groundwater quality in the Bizerte landfill for an integrated sustainable environmental assessment.