Visalia Landfill

Project Summary
A true double lined landfill liner system in Central Valley of California. The liner system consists of the following from the bottom up: Subgrade/GCL/White-black double sided textured HDPE geomembrane/High Flow Geocomposite/one foot of clay (low perm soil layer)/GCL/White-black double sided textured HDPE geomembrane/High flow Geocomposite/Operations soil layer. Interface shear testing was completed at loads up to 18,000 psf. A high peel strength GCL (manufactured by Ceto) and differential texturing on the top and bottom side of the geomembrane ( was required to meet the 17 degrees residual shear in the multilayer interface shear testing. The landfill when completed will be 250 feet high. A special 330 mil high flow biplanar geocomposite was necessary for the long term creep resistance under high loads. Meeting the interface shear testing requirements successfully was challenging and could only be accomplished by special texturing of the HDPE geomembrane and the use of a high peel strength double non-woven GCL.