Waste Disposal Sites Investigation by the Use of Electrical Resistivity Tomography

Management of waste disposal is a major issue that authorities had and still have to deal with. The construction of landfills used to be the main way to manage the great volume of waste. At the present time, the construction of sanitary landfills is the dominant option in Greece, while old waste disposal sites where no protection standards had been followed still exist. In both cases, geological and hydrogeological setting of these areas is of a major importance. In this paper, two cases studies are presented. One case refers, to the active sanitary landfill of Thessaloniki where during the remediation of a new cell, underground water has been found. This was a major problem for the construction of the new landfill since water flow beneath the geomembrane can be destructive. The detection of the flow path and the confrontation of the problem was very important. Resistivity survey allowed the mapping of the underground water flow and appropriate measures have been taken according to the suggestions of the geophysical results. In the second case, an old waste disposal site has been investigated since outflows of leakage occurred. The flow paths of the leakage have been detected and remediation measures have been suggested.