Appraisal of groundwater vulnerability in south-central part of Bangladesh using DRASTIC model: An approach towards groundwater protection and health safety

Abstract

Groundwater intrinsic vulnerability maps are considered a promising means for forestalling groundwater resources from contamination during recent years. In the present study, the DRASTIC model was used to predict groundwater vulnerability using hydro-geochemical data and Geographic Information System (GIS). The DRASTIC vulnerability index showed that the aquifer system of the study area (57%) was at moderate risk in terms of pollution. The groundwater quality index (GWQI) indicated that 89% of the study area exhibited poor water quality and was unsuitable for drinking. The mean hazard index (HI) for three age groups was higher than the threshold limit (1), suggesting potential non-carcinogenic public health threats. Carcinogenic risk (CR) showed wide variations with ranges between 1.2 × 10−4 and 4.6 ×10−2, and all of the sampling sites exceeded the threshold limit (CR> 10−4), which suggests people might have experienced a lifetime cancer risk. Among three categorized age groups, Group 2 (6–15 years) was the most vulnerable. However, it has been expected that this work will helps the decision maker for better manage groundwater resources in the study area.