Installation of geosynthetic clay liners at California MSW landfills

The California regulations for liner systems at municipal solid waste (MSW) landfills require that alternatives to the prescriptive federal Subtitle D liner system have a containment capability greater than that of the prescriptive system. Regulators may also require a demonstration that use of the prescriptive system is burdensome prior to approval of an alternative liner design. This paper presents seven case histories of the design and installation of geosynthetic clay liners (GCL) as an alternative to the low-permeability soil component of the prescriptive Subtitle D composite liner system at MSW landfills in California. These case histories cover GCLs from different manufacturers and landfill sites with a wide range of conditions including canyon landfills with slopes as steep as 1H:1V.