场地平整前后地下水流场变化对预测结果影响研究

Study on Prediction about Groundwater Flow Field and Pollutants Migration Characteristics Caused by Topography Changes

在地下水环境影响评价中,往往会忽略地形地貌改变导致的地下水流场变化,由此可能造成影响预测结果的偏差。以某新建石化项目为例,利用GMS软件分别建立项目建设前、后所在水文地质单元的数值模型,对两者的地下水源汇项及流场变化进行对比分析,并预测事故工况下污染物泄漏对地下水及环境敏感目标的影响变化情况。研究结果表明,项目场地地形地貌发生改变,会导致局部地下水流场特征发生一定程度的变化,产生不同的预测结果,从而影响后续的减缓措施及监测方案设计。

In the process of groundwater environment impact assessment of project, the change of groundwater flow field which caused by topography change used to be ignored and the impact prediction deviation would also appear as a result. A new petrochemical project was taken as an example and GMS software was used as a tool to set up a numerical model of the hydrogeological unit in which the project site located. Variations of the source and sink item of groundwater and the flow field before and after site formation were compared and analyzed. The different influence on groundwater sensitive targets under accident conditions was also predicted and evaluated. The results indicate that groundwater flow field characteristics will change in a certain degree due to the change of site topography, and pollutant migration and the environmental impact will show different characteristic and extent.