Surface Capping of Waste Disposal Sites with Natural Liner Materials

摘要

At waste disposal sites the construction of surface caps is only efficient if the infiltration of rainwater can be reduced significantly. This is only possible with bentonite or other swelling clay soils, and in certain cases the infiltration may become even zero under field conditions. Field experiments showed no leakage at all through a 20 cm surface cap of bentonite during 3.5 years in spite of large settlements. Since the hydraulic conductivity is not a constant at low hydraulic gradients, the permeability of clay liners should be expressed as annual leakage (in mm/year) under field conditions. (Copyright (c) 1988, Institute for Land and Water Management Research.)