Risk assessment of sources of groundwater pollution, groundwater vulnerability, and groundwater value: A case study in the plain area of Northeast Beijing

Abstract

There is growing evidence of increasing pollution threats to groundwater resulting from anthropogenic activities. Assessments of the risk of groundwater contamination are useful for preventing and controlling groundwater pollution. This study established a quantitative evaluation model based on the origin–pathway–target model. The target, guideline, and indicator layers were established through a comprehensive analysis of the distribution of pollution sources, hydrogeological conditions, and other conditions in the northeastern plain area of Beijing by applying the hierarchical analysis method. Each assessment index was quantified and analyzed based on the groundwater pollution risk assessment index system, and the risks associated with pollution sources, groundwater susceptibility to pollution, and groundwater value in the study area were evaluated. The comprehensive assessment results were superimposed by the matrix method and the pollution risk classification was conducted using the ArcGIS platform. Grade Ⅰ to Ⅴ pollution risk areas accounted for 12.5%, 28.5%, 23.2%, 26.1%, and 9.7% of the total area, respectively. The V pollution risk area was mainly in the central and northeastern part of the Beijing plain area and agriculture and industry were the main sources of pollution in the central and northeastern areas, respectively. The study area had a large net recharge, soils were dominated by sand and gravel, and there was a high permeability coefficient. The study area also showed poor groundwater pollution prevention performance, which resulted in the infiltration of pollutants into the groundwater environment. The V pollution risk area contained sensitive groundwater targets, and the pollution index, groundwater richness, annual average groundwater extraction, and risk of pollution were high.