Groundwater vulnerability assessment using a GIS-based DRASTIC method in Erbil Dumpsite area (Kani Qirzhala), Central Erbil Basin, North Iraq

Abstract

Abstract Groundwater vulnerability assessment is an essential step for the efficient management of groundwater resources, especially in areas with intensive anthropogenic activities and groundwater pollution. In the present study, the DRASTIC method was applied using geographic information system (GIS) to evaluate groundwater vulnerability zones in Erbil Dumpsite area, Central Erbil Basin, North Iraq. Results showed that the area was classified into the following vulnerability classes: very low (16.97%), low (27.67%), moderate (36.55%) and high (18.81%). The southern, south-eastern and northern part of the study area had the highest vulnerability potential, whereas the central-northern, northern and north-western portion of the study area revealed the lowest vulnerability potential. Moreover, results of the single-parameter sensitivity analysis showed that amongst the seven DRASTIC parameters the unsaturated zone and the aquifer media were the most influencing parameters. Finally, the correlation of 25 nitrate concentration values with the final vulnerability map, using the Pearson correlation coefficient, gave a satisfactory result equal to R = 0.72.