Geoelectrical Resistivity Monitoring for Localizing Gas at Landfills

In order to assess the potential of electrical resistivity for imaging gas migration at landfills, two relatively well-known sites - one bioreactor landfill and a conventional landfill - have been monitored successively. A three-dimensional resistivity image could be constructed every two hour on both sites. Meteorological parameters were monitored at the same time, with one measurement taken every hour. Methane concentration was measured in the air at several occasions, the pore pressure was monitored at two locations and some relative estimations of moisture in the top layer were made at the second site. The results show imperfect but interesting correlations between the different parameters and give a hint of how the method could be refined. The resistivity depends on several parameters, but the areas where the resistivity is most variable seem to be clearly related to higher gas emissions.