Semi-automatic Mobile Equipment Test for Detecting Holes in Geomembranes – the Prototypes Evolution

Landfills contain basal lining systems that include composite liners, among which a geomembrane (GM). The success of these systems depends mainly on the GM performance, which acts as the primary barrier to contaminants migration. GM performance is conditioned by the presence of holes, which represent preferential pathways for leachate migration. An equipment was developed to detect holes in geomembranes. It is based on the geophysical resistivity method and aims to overcome the main disadvantages of the existing methods for GM holes detection, mainly time spent to perform the tests and the associated high costs. Several prototypes were already developed and were tested at small scale in laboratory. The final version, which is the model for the equipment under construction, was already successfully tested at laboratory small scale pilot plant and in a large pilot plant at Laboratorio Nacional de Engenharia Civil, I.P. (LNEC) campus. This paper presents the prototypes development and results so far obtained.