A Study on Arsenic Distribution Characteristics in Groundwater of Western Jilin Province, P. R. China

The study area is physiogeographically located along the western flank of Songnen Plain, and hydrogeochemically distinguished as a basin with groundwater generally flowing easterly. A total of 196 groundwater samples were collected to not only cover the whole study area but also to extend in different aquifers that include Quaternary phreatic groundwater, Quaternary Baitushan Formation confined groundwater and Neogene confined groundwater. Simulated and depicted by GIS spatial data overlay technique, the analytical data indicated that arsenic distribution is naturally controlled by the hydrogeochemical environment of the basin. The centralized hotspot pattern of the arsenic distribution in groundwater, especially in the depressed area, appears to originate in the very thick silty mud sediments of lacustrine origin which is rich in organic matter. The simulation results confirmed that the arsenic presence and its distribution in the area groundwater are largely formed by the leaching-migration-accumulation from the edge to the central area of the basin. The study finally concludes that the presence of arsenic in the regional groundwater flow regime exhibits the highest concentration in chloride-sodium bicarbonate groundwater in the central area and is consistent with the above findings and many previous studies in this special field of the international community.