Geosynthetic Clay Liners (GCLs) are frequently used in place of compacted clay liners. GCLs are composed of layers of geosynthetics surrounding a layer of low-permeability sodium bentonite. The layers are needlepunched together in to a lining material that is resistant to shear forces. GCLs are optimal solutions for steep slopes and are resistant to fluctuating weather conditions. These products offer quick and easy installation with a self-seaming capability that reduces the need for bagged bentonite and additional labor.