Organic contamination characteristics of shallow groundwater in a study area of the Taihu Lake basin,Jiangsu,China

The authors have summed up the characteristics of organic contamination of shallow groundwater in a study area of the Taihu Lake basin and studied the contamination sources,pathways and characteristics of organic contamination of shallow groundwater near typical contamination sources. The results show that the detection probabilities of compounds in groundwater are higher but the concentrations of the compounds are lower. The concentrations of all the components of BTEX and halocarbons are lower than the standards set by the U.S. Environmental Protection Agency (EPA) for drinking water except for benzene in a few sampling sites. In plan views,the higher concentration points are mostly found in the southeastern industrial zone of the study area. Such spatial distribution characteristics are apparently consistent with the distribution of the industrial zone. Vertically,the contamination of shallow groundwater is stronger,while that of deep groundwater is weaker. The contamination in shallow wells around typical contamination sources is more serious. However,as the distance of the sampling sites away from the typical contamination sources increases,the concentrations of various organic contaminants decline rapidly.