垃圾填埋场地下水污染风险分级评价

为了更有针对性地解决垃圾填埋场造成的地下水污染问题，有利于分级管理及合理安排资源，构建包括垃圾填埋场特征、含水层脆弱性和受体暴露情况的风险评价指标体系，使用AHP（层次分析法）确定各指标的权重，采用加权求和的方法计算垃圾填埋场地下水污染风险指数，并将垃圾填埋场的地下水风险分为“低”“中”“高”三级，针对不同风险等级提出相应的管理建议.以北天堂垃圾填埋场的4个填埋地块为例，运用所构建的风险评价模型对其进行风险评价.结果表明:4个填埋地块的风险指数分别为5.307、5.845、7.001和7.413.位于东北部和北部的填埋地块1和2风险等级为“中”，位于西北部和南部的地块3和4风险等级为“高”.研究显示，通过垃圾填埋场地下水污染风险评价体系，可以识别出填埋场污染的关键环节，对风险等级为高、已经造成污染的填埋场污染提出有针对性的治理和修复措施，对风险等级为低和中的填埋场，制订相应的监测和管理方案，防止污染发生. 

Risk Assessment System for Groundwater Pollution from Landfills

Landfills could cause serious groundwater pollution. Groundwater risk assessment for waste landfills could recognize the hazard status of groundwater and surroundings, and benefits level-to-level administration and intelligently resources usage. It could help solving the groundwater pollution caused by waste landfills specifically. Based on the factors of groundwater pollution, a risk assessment index system including landfill characteristic, aquifer vulnerability and exposure of evaluation objects was established. Analytical hierarchy process (AHP) was used to determine weights of each evaluation index, and sum operation with confident was used to calculate the risk index of groundwater pollution for landfills. According to the calculation results, risk of groundwater pollution was graded in low, medium and high levels, and management suggestions was put forward according to the different levels. Four landfills in Beitiantang were studied to evaluate the pollution risk using risk assessment. The four landfills'' risk indexes are 5.307, 5.845, 7.001 and 7.413. The result showed that the risk level of the northeast landfill 1 and northern landfill 2 were medium, and the northwest landfill 3 and the south landfill 4 were high.