Landfill Liner Systems-The Geomembrane
A geomembrane is an essentially impermeable membrane used with foundation, soil, rock, earth or any other geotechnical engineering-related material as an integral part of a structure or system designed to limit the movement of liquid or gas in the system.
liner system exposed on the side slopes.
Application of a geo-
membrane liner above
a low permeability
clay foundation.
Geomembrane liner
seams are sealed in
the field with a high
temperature "wedge weld."
Vacuum testing one
of several ways that
seams between geo-
membrane panels
are tested.
A leachate collection
layer is placed above
the geomembrane.
Very low density polyethylene (VLDPE) and polyvinyl chloride (PVC) are materials typically used in the manufacture of geomembranes for final covers of solid waste landfills. Forty mil thick VLDPE or forty mil thick PVC may be used in the final cover. (A mil is 1/1000 of an inch.)
The geomembrane used in the landfill liner systems must be 60 mil thick and must be made of a material (such as high density polyethylene (HDPE)) that is extremely low in permeability. The material must also have chemical and physical characteristics that are not adversely affected by the placement of waste or by contact with leachate.
