Conductive backed geomembranes are geomembranes with an electrically charged backing that allows leaks to be found without the need for a conductive subgrade or underlay beneath the geomembrane. The absence of a conductive underlay beneath a geomembrane may be a limiting factor for finding leaks in a lined system with commonly used electric leak location survey techniques. A conductive underlay is needed for current to flow from a source electrode through a leak in the liner to a receiving electrode with these survey techniques. The conductive backed geomembrane overcomes this limitation and several others that may arise with electric leak location surveys on nonconductive geomembranes, making it possible to find leaks in various site conditions. This paper reviews the benefits of conductive backed liners for leak location surveys.The review presented here was completed using results from field based leak location surveys in the literature and some pilot scale studies. One of the studies reviewed showed that zero leakage can be achieved in a containment facility when the facility is lined with conductive backed geomembranes and leak location surveys are completed on the bare geomembrane after installation and on the covered geomembrane after placing backfill material. The study also showed that the performance of conductive backed geomembranes can be enhanced with a white upper surface.
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