A GIS-based analysis of intrinsic vulnerability, pollution load, and function value for the assessment of groundwater pollution and health risk

Abstract

Groundwater pollution risk assessment is an effective tool for the control and prevention of groundwater pollution. However, the risk is generally difficult to interpret because it is affected by both natural and anthropic factors such as topography, aquifer characteristics, land-use changes, and mining process. In this study, a GIS-based analysis of aquifer vulnerability (V), groundwater pollution load (L), and groundwater function value (F) were combined to comprehensively evaluate the groundwater pollution risk in a typical mixed land use area of Chengdu Plain, in China. Groundwater pollution risk assessment was then validated by a groundwater quality evaluation using the comprehensive water quality index method. A health risk assessment was conducted to evaluate the susceptible population exposed to the groundwater pollution. The results showed that the estimated ‘high’ and ‘very high’ pollution risk areas together accounted for 24.85% of the study area, mainly located in the southeast and southwest of the plain area with highly permeable aquifer, abundant amounts of groundwater storage, a shallow water table, and near pollution sources. In addition, our results revealed that 14% of groundwater in the study area posed an unacceptable non-carcinogenic health risk to children. The risk assessment of groundwater pollution and human health in the study area can provide effective support for strengthening groundwater management and pollution control.