1.5 mm HDPE geomembrane was selected. The upper and lower layers of the geomembrane are covered with a geotextile layer of 300g/m2. (The geotextile for the bottom blind ditch is 400g/m2). The supporting layer is 200 mm clay layer. And the protective layer is 300 mm clay layer.
Before laying HDPE geomembrane, debris that may damage HDPE geomembrane should go out at the bottom of the landfill reservoir. Such as tree roots, broken glass, stones and so on.
When laying backfill, the compactness of backfill should be ≥ 95%. And the weld lap width of HDPE geomembrane ≥100mm.
Some areas have steeper slopes. In this case, the supporting layer and protective layer are difficult to lay. Therefore, the treatment of slope seepage prevention is different from that of ground floor seepage prevention.
Slope seepage control generally has two ways.