京津冀典型区域地下水污染风险评价方法研究

Groundwater Pollution Risk Assessment Method in a Typical Area of Beijing-Tianjin-Hebei Region

地下水污染风险评价是开展京津冀地区地下水污染防控工作的基础,对于保障京津冀地下水环境安全至关重要.为了有针对性地开展京津冀地区地下水污染防控工作,以京津冀地区内某典型区域为研究区,提出了一种基于HYDRUS-2D软件的地下水污染风险评价方法,并以研究区内特征污染物硝酸盐为对象进行地下水污染风险评价.结果表明:①研究区内地下水污染荷载主要受垃圾填埋场分布影响,其次为工业源和农业面源;②包气带结构类型不变的情况下,污染源荷载的变化只会导致进入含水层中的污染物浓度不同,不会改变包气带硝酸盐折减系数;③污染源类型、包气带介质岩性及厚度是造成研究区内地下水硝酸盐污染风险评价存在差异的主要原因.研究显示,采用基于HYDRUS-2D软件的地下水污染风险评价方法,能够有效地降低地下水污染评价过程中的主观性,对于确定京津冀地区地下水污染重点防控区域,提高地下水环境管理水平具有重要的参考价值.

Groundwater pollution risk assessment is the basis of groundwater pollution prevention and control in the Beijing-Tianjin-Hebei Region,which is essential for ensuring the safety of the groundwater environment in Beijing-Tianjin-Hebei Region.In order to prevent and control groundwater pollution in the Beijing-Tianjin-Hebei Region,a groundwater risk assessment method using HYDRUS-2D software was established for a typical area in the Beijing-Tianjin-Hebei Region.This method was used to assess the groundwater nitrate pollution risk in the typical area.The results show that:(1)Groundwater pollution load in the study area is mainly affected by the distribution of landfills,followed by industrial sources and agricultural non-point sources.(2)Under the condition that the structure of the aeration zone remains unchanged,changes in the load of the pollution source will only cause different concentrations of pollutants to enter the aquifer and will not change the reduction factor of the aeration zone.(3)The main reason for the difference in groundwater pollution risk assessment results was the type of pollution source,the lithology and thickness of vadose zone.The research shows that the groundwater pollution risk assessment methods based on HYDRUS-2D software can effectively reduce the subjectivity of the groundwater pollution assessment process,which has important reference value for determining the key prevention and control areas of groundwater pollution and for improving the level of groundwater environment management in the Beijing-Tianjin-Hebei Region.