Evaluation of aquifer vulnerability of Jovein Plain using DRASTIC and GODS methods

Aquifer vulnerability assessment is useful to development, management and landuse decision, quality monitoring and contamination prevent of water resource. The DRASTTIC and GODS methods have used increasingly for vulnerability assessment in regional scale. Objects of this research are aquifer vulnerability mapping of the Jovein plain, sensitivity analysis of the DRASTIC model to determine the parameter effects on the model and comparison of the DRASTIC and GODS results. The aquifer vulnerability of the Jovein plain in the both methods is categorized in the low and moderate vulnerability groups. Area of low and moderate vulnerability in the GODS method respectively is 35 and 65 percent of the plain area and for DRASTIC method is 49 and 51 percent of the plain area. Then the DRASTIC method underestimate aquifer vulnerability to GODS method. Sensitivity analysis has done with two methods of single-parameter and map removal. Sensitivity of vulnerability index respectively decrease to vadose zone, aquifer media, soil type, topography, depth to water, net recharge and hydraulic conductivity in the single-parameter method. Sensitivity of aquifer vulnerability respectively decrease to vadose zone, depth to water, net recharge, hydraulic conductivity, aquifer media, topography and soil type.