Use of Electrical Resistivity Methods (2-D and VES) in Proposed Landfill Site Investigation – A Case Study of Al Fukhari Landfill, Southeastern Gaza Strip, Palestine

Abstract

Electrical resistivity tomography (ERT) and vertical electrical sounding (VES) are widely used in environmental and engineering purposes. In the present study, both ERT and VES were used to investigate the suitability of a proposed landfill site area in south of Gaza Strip, Palestine to delineate the presence of any linear structure, depth and characterization of the unsaturated zone, layer resistivities, soil type, bedrock depth and subsurface structures with priority of groundwater protection. Measurements procedure for electrical imaging resistivity survey is taken along 9 spreads with Wenner-Schlumberger configuration with maximum spread length of 115m, in E-W and N-S direction, in addition to three VES points with Schlumberger configuration with electrode spacing (AB/2) ranging from 0.5 to 150 m. VES location has been selected much closed to the 2D lines and near the proposed boreholes to integrate all the data. Data from 6 drilling boreholes (up to 25m depth) and 14 drilling test pits (up to 5m depth) are also used to support the geophysical models. The proposed geoelectrical models show that resistivity values change horizontally and vertically as a result of  inhomogeneous of soil contents. Top soil layers and dry Sands are characterized by high resistivity values, whilst low resistivities reflect  a Clay or Silty Clay layers to Sandy Clay layers. Layer thicknesses and the subsurface structure proposed by the geoelectrical interpretation showed a good correlation with that of the boreholes and drilling test pits.

Keywords: Electrical Resistivity Tomography, VES, Landfill Investigation, Al Fukhari , Gaza Strip, Palestine.