关键词: 地下水, 重金属, 垃圾焚烧, 风险评价

Abstract: To understand the groundwater environmental status around waste incineration plants in Xi’an, pH and the contents of Fe, Mn, Cu, Cd, Pb， Ni, As， Se in the collected groundwater samples were measured. The Nemerow comprehensive pollution index and entropy weight water quality index were used to evaluate the pollution status, and the health risk model was combined to assess the health risks caused by different exposure pathways. The results showed that in groundwater during the wet season, normal season and dry season in this area, Cd had the lowest content, while Fe had the highest content. In the study area, the Fe and Mn contents at the GL-N groundwater point exceeded the standard, while the other points did not exceed the standard. The pH value ranged from 6.88 to 8.16, all complying with class Ⅲ standards specified in GB/T 14848—2017 Standard for Groundwater Quality. According to the Nemerow index, only the GL-N point showed mild pollution due to the exceedance of Fe and Mn standards, while other points were in a clean level. The entropy weight water quality index indicated that the overall water quality in the region was excellent, and Fe and Mn contributed 78.6% to the pollution at the GL-N point. Health risk assessment showed that in non-carcinogenic risks, As and Cd had the highest hazard quotients,but both were less than 1. All carcinogenic risk values were below the threshold 10-6, with the carcinogenic risk of As being higher than that of Cd. Drinking water was the main exposure pathway for Cd, and children were more sensitive to Cd.

Key words: groundwater, heavy metals, waste incineration, risk assessment