Abstract：
Landfill is an important means of municipal solid waste treatment. Previous studies have shown that the combination of \"cut-off wall and pumping well\" technology is an effective measure to deal with the leachate emission reduction and pollution control of landfill, and has been widely used in plain areas. However, for landfills in hilly areas with complex terrain and geological conditions, there is still a lack of clear and referable ideas and operational strategies for leachate emission reduction and pollution control. In this study, we proposed strategies for determining the position and depth of cut-off walls and pumping wells and reasonable combinations of the cut-off wall depth and pumping quantity for leachate reduction and pollution prevention of landfills in hilly areas. The determination of leachate reduction and pollution control strategy need to be achieved in two stages, qualitative and quantitative: (1) In the qualitative stage, the natural conditions (Weathering degree, groundwater flow characteristics, topography condition, hydrometeor condition, and aquifer thickness) and engineering conditions (Operation status, landfill location, and excavation status) of the study area are analysed in detail, and then the depth range and location of the cut-off wall and pumping well are determined. (2) In the quantitative stage, we need to quantify the combination of the cut-off wall depth and pumping quantity by using profile particle tracing and pollutant transport modelling. A reasonable cut-off wall depth needs to control the leakage of pollutants inside the wall, and a reasonable pumping quantity needs to ensure that the depth of the pollutant distribution is equivalent to the depth of the separation line, which separates the water flow towards the pumping well and the water flow downstream. (3) The effectiveness of the leachate reduction and prevention strategies proposed in this study was verified through an example of a landfill in Northeast China. This study provides a reference and operation method for leachate emission reduction and pollution control of landfills in hilly areas.
摘要：
填埋是城市生活垃圾处理的重要手段。以往的研究表明，“防渗墙和抽水井”技术相结合是应对垃圾填埋场渗滤液减排和污染控制的有效措施，在平原地区得到了广泛的应用。然而,对于地形和地质条件复杂的丘陵地区的垃圾填埋场，渗滤液减排和污染控制仍然缺乏明确和可参考的思路和操作策略。在这项研究中,我们提出了确定防渗墙和抽水井位置和深度的策略，以及防渗墙深度和抽水量的合理组合，以减少山区垃圾填埋场的渗滤液和污染。渗滤液减少和污染控制策略的确定需要分两个阶段来实现，定性和定量：(1)在定性阶段，自然条件(风化程度，地下水流特性,地形条件,水星条件，和含水层厚度)和工程条件(运行状态，填埋位置,和开挖状态)对研究区进行了详细分析，然后确定了防渗墙和抽油井的深度范围和位置。(2)在定量阶段,我们需要通过使用轮廓颗粒追踪和污染物传输模型来量化截止墙深度和泵送量的组合。合理的隔墙深度需要控制墙内污染物的泄漏，并且合理的泵送量需要确保污染物分布的深度等于分离线的深度，它将流向抽水井的水流和下游的水流分开。(3)通过东北地区某垃圾填埋场的实例,验证了本研究提出的渗滤液减量防治策略的有效性。该研究为丘陵地区垃圾填埋场渗滤液减排和污染控制提供了参考和操作方法。
