Assessing aquifer vulnerability in Khazarabad plain with DRASTIC method

Surface contaminants entering into groundwater resources, especially in arid and semi-arid regions that faced with quality and quantity restrictions on water resources, is a serious problem. Therefore, identifying vulnerable areas and driven development programs to low-risk areas is essential to achieving sustainable development in water resources management. Hence, this paper tries to zoning aquifer vulnerability to contaminant factors based on hydrological and hydrogeological features of the study area. For this aim drastic model and geographical information system has been used for processing and analysis of groundwater quality. Drastic model is used from effective characteristics in aquifer vulnerability assessment including: aquifer depth, aquifer recharge, aquifer type, soil type, slope, topography, Ingredients unsaturated zone and electrical conductivity that provided in Arcview software as 7 layers. Finally the Map of aquifer contaminant was provided according to ranking, weighting and combining layers and drastic index for the whole area was estimated at 45 to 142. The result showed that 11.75% of the study areas in South and South West are highly vulnerable and 42.99% are moderate vulnerability.