Due to the difficulty of constructing a single large scale impermeable layer without any defects, a double liner system is more robust, as it can deal with leakage through the primary liner.
A double liner system is required by the United States EPA for landfill, surface impoundments, and waste piles.
[2] The first double geomembrane liner system was designed by geosynthetics pioneer J.P. Giroud, and installed in 1974 in Le Pont-de-Claix, France to serve as a water reservoir; this is still in service today.
This system was composed of an early form of a bituminous geomembrane as the secondary liner, gravel as the drainage layer, and a butyl rubber geomembrane as the primary liner.
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