Author(s): Seyed Mahmood Sadat-Noori; Kumars Ebrahimi
Linked Author(s):
Keywords: Groundwater vulnerability; Chloride; Statistical Techniques; Improved DRASTIC Method
Abstract: The main goal of this paper has been to highlight the results gained from a newly modified DRASTIC method compared to the original method. In this paper in order to determine the potential pollution vulnerability map more accurately, the DRASTIC parameter rating function has been modified and optimized. The mentioned refinement includes the use of statistical and geostatistical techniques for the revision of the rating and weighting of the DRASTIC parameters with the help of GIS. The new rates were computed using the relationships between each parameter and the point data chloride concentration of the groundwater. The modified method has been applied to the Saveh-Nobaran basin, Iran. According to the results, although, the correlation coefficient between the points measured data and the relevant vulnerability map, before modification, was only about 52% , but after that it rose to 78% . Results of this study show that chloride concentration could be used as a modifying parameter with considerable improvement in the resulting index that could lead to a better groundwater quality management. Also, the results show that for nonpoint source pollution in agricultural areas, using this modified DRASTIC model is more efficient compared to the original method. The proposed method is suggested for agricultural areas with extensive use of chloride, where accumulation of chloride in groundwater is mainly due to leaching from the soil surface. Therefore, it is necessary to calibrate and modify the original algorithm in order to obtain more accurate results. The presented method could be very efficient for managing both land use and groundwater for a sustainable development.
Year: 2013