Assessment of aquifer vulnerability for pollution for middle delta in Egypt using Geographic Information System and DRASTIC technique

Abstract

Egypt is one of the countries suffering from water poverty, so researches must be increased about groundwater as a clean source of water. Aquifer vulnerability has assessed using the DRASTIC method, based on a Geographic Information System (GIS) to evaluate the relative importance of the model parameters for aquifer vulnerability in middle Delta Gharbiya Governorate (Egypt). An additional objective is to demonstrate the combined use of the DRASTIC with GIS system as an effective method for groundwater pollution vulnerability. The DRASTIC model uses seven hydrological factors (Depth to water, net Recharge, Aquifer media, Soil media, Topography, Impact of the vadose zone, and hydraulic Conductivity) to characterize the hydrogeological setting and evaluate aquifer vulnerability. A DRASTIC vulnerability map, verified by nitrate in groundwater data, shows that the defined areas are compatible with land-use data. It is concluded that these values were reclassified into four classes, low (132-146) "24%", medium (146-159) "30%", high (159-172) "35%", and very high "11%”, of the study area, respectively.