HAN Cong1，GAO Zongjun1，LIU Jiutan2，LI Fuquan3，ZHANG Yongshuai3，LIU Ruinan1，FENG Chaochen3
（1.College of Earth Science and Engineering，Shandong University of Science and Technology，Qingdao Shandong 266590，China;
2.College of Energy and Mining Engineering，Shandong University of Science and Technology，Qingdao Shandong 266590，China;
3.Seventh Geological Brigade，Shandong Bureau of Geology and Mineral Exploration and Development，Linyi Shandong 276006，China.）
Abstract: Based on the monitoring data of 100 groundwater samples in Tancheng area, the chemical characteristics of water were summarized, the contributing factors were analyzed, and the health risk assessment of nitrate was carried out in view of the problem of nitrogen pollution. The results show that groundwater in Tancheng area is weakly alkaline, with low salinity and medium hardness. The hydrochemical types are mainly HCO3-Ca type, but nitrogen pollution is serious. The chemical composition of groundwater is mainly controlled by rock weathering and agricultural fertilization, and the weathering dissolution of carbonate and silicate rocks and the application of nitrogen fertilizer are the main causes of the current situation of hydrochemistry. The entropy water quality index (EWQI) show that the groundwater in the area's overall water quality is good, while, Ⅳ classes and class Ⅴ accounted for 11% and 2% of the samples. In the northwest and east areas, where agricultural activities are strong, nitrate levels exceed the standard that accounts for about 60% of the total area. Based on the health risk assessment model, four groups of people, namely infants, children, adult male and adult female, were evaluated respectively. The results show that long-term consumption or exposure to groundwater with excessive nitrate content in this area will bring great risk to infants and children.
Key word: Tancheng area; hydrochemistry characteristics; groundwater quality assessment; nitrate health risk
EARTH AND ENVIRONMENT Vol.49, No.4, Tot No.342, 2021, Page 436-446