甘肃某生活垃圾填埋场地下水污染特征及污染途径分析

依据实际调查数据，采用单因子污染指数分析法确定了生活垃圾填埋场地下水中主要污染物、污染程度和污染范围，并进行了土壤和地下水污染耦合性分析，研究结果表明：该生活垃圾填埋场地下水污染物主要为氨氮、总氮、高锰酸盐、锰、挥发酚和氟化物，其污染指数最大值分别为1 407.24、745.00、137.12、97.50、3.60和1.68，污染区总面积0.168 km²；填埋场下游沟谷纵向上，总氮、锰两项指标在土壤中的含量与地下水中浓度变化趋势一致；其污染途径主要为库区防渗层破损，渗滤液垂向沿基岩风化裂隙进入地下含水层，以连续渗漏的方式不断污染地下水，污染物在地下水径流作用下向拦挡坝下游不断迁移。

Groundwater Pollution Characteristics and Pollution Paths of A Houosehold Waste Landfill in Gansu Province

With mutual-coupling analysis of soil and groundwater contamination employed, single factor pollution index analysis has been used to deal with accurate data for determination of most pollutants, pollution levels and scope in the groundwater under a household waste landfill. The results have demonstrated that most groundwater pollutants in the household waste landfill are ammonia nitrogen, total nitrogen, hypermanganate, manganese, volatile phenol and fluoride. The maximum pollution indexes of them are 1407.24, 745.00, 137.12, 97.50, 3.60 and 1.68 respectively, with the total area of 0.168 km² contaminated zone. The contents of total nitrogen and manganese in the soil is consistent with change of concentrations of those in groundwater. The major paths to pollution result from the damaged impermeable layers in the landfill, and then landfill leachate flowing vertically into sub-surface aquifers along weathering fissures of bedrock. The latter successively pollutes groundwater because of unremitting leakage, and these pollutants keep moving toward the downstream of the retaining dam by groundwater runoff.