典型场地地下水污染源强分级评价方法研究

Study on groundwater pollution source intensity rating assessment method of typical contaminated sites

地下水污染程度评价是地下水研究领域的研究热点。以场地浅层地下水为研究对象,基于目前国内工业场地有无防渗措施的分类原则,综合考虑污染源和场地包气带特征因子,构建了地下水污染源强分级评价指标体系。将修正的内梅罗污染指数法应用于污染源危害性分级,并将改进后的DRTAS模型应用于包气带阻控性分级,利用矩阵法构建两方面多因素耦合模型,最后形成了适合典型工业场地的地下水污染源强分级评价的方法。选择4个典型污染场地对评价方法进行实地验证,分析结果表明,对于已建的或拟建的有防渗措施的项目,污染源危害性是造成场地地下水污染的主因;对于已建的无防渗措施项目,污染源危害性和包气带阻控性共同决定地下水污染源强。场地评价结果与水质监测报告结论相符,说明本研究建立的分级评价方法对于地下水污染的预防和控制具有借鉴意义。

Groundwater pollution degree assessment is the hot spot in groundwater pollution research. Field shallow groundwater is taken as research object. Based on the current classification principles with /without antiseepage measures in the domestic industrial sites,characteristic factors of pollution sources and field vadose zone are considered,and the grading evaluation index system of groundwater pollution source intensity is constructed.The amendment Nemerow pollution index is applied to hazard gradation of pollution sources,and improved DRTAS model is applied to resistance gradation of vadose zone. Accordingly,two aspects multi-factor coupling model by matrix method is formulated,and grading evaluation method of groundwater pollution source intensity suitable for typical industrial sites is finally presented. Four typical contaminated sites are selected to verify the evaluation method,and the analytic results show that the hazard of pollution sources is the main cause of groundwater contamination for already built or proposed projects with anti-seepage measures; the groundwater pollution source intensity is jointly decided by the hazard of pollution sources and the resistance of vadose zone for already built projects without anti-seepage measures. The evaluation results of these sites are consistent with the conclusions of water quality monitoring report,which means that the presented grading evaluation method in this paper is an important reference for the prevention and control of groundwater pollution.