HYDRAULIC PERFORMANCES OF NATURAL AND POLYMER TREATED BENTONITES IN SHORT AND LONG TERM LANDFILL CONDITIONS

Summary The paper presents experimental results relative to the hydraulic performances of a natural bentonite, used in a manufactured geosynthetic clay liner (GCL). Short and long term landfill conditions are considered in order to estimate the change in hydraulic conductivity of the GCL during the whole landfill life. In order to enhance the resistance of sodium natural bentonite to sodium-calcium exchange, that causes a compression of the diffuse double layer (DDL), different polymer-treated bentonites have been prepared. Preliminary hydraulic conductivity test results are reported in order to assess the potential benefits that can be obtained by these advanced materials.