Sealing of waste disposal sites

摘要

Waste disposal sites are sealed, from underlying soil, with a primary sealing layer covered with a secondary sealing layer, eg. of plastics sheeting. The primary layer comprises a combination of gravel or broken stone, sand, silt and clay cold-mixed with a bituminous binder to give a mixt. with a clay content above 3%, a water permeability of 5 x 10<-10> m/sec or less, and sufficient stability and water resistance to support the secondary layer.Pref. the mineral/bitumen mixture is prepared on site by a `mix-in-place' process. This provides a watertight seal.