Detailed Mapping of a Leachate Plume from a Landfill Using Full-decay Time-domain DC-IP

摘要

Leaching of organic and inorganic contamination from landfills are a serious environmental problem as surface waters and aquifers are being contaminated. In order to assess these risks and investigate the migration of leachate from the landfill, several time-domain DCIP profiles have been collected at a heavily polluted landfill in Grindsted, Denmark. The DCIP data were inverted using a new 2D DCIP inversion code inverting for a full cole-cole model while modelling the full system transfer response including waveforms, gates and low-pass filters. The inverted profiles describe both the variations along the groundwater flow as well as the plume extension across the flow directions. Chemical analysis of borehole data agrees well with the observations indicating a leachate plume which gradually sinks and increases in size while migrating from the landfill in the groundwater flow direction. High chargeabilities are seen on the landfill itself but there are only small IP effects in the leachate migrating from the landfill. The information obtained from the DCIP results will be combined with chemical analysis in order to compute contaminant mass discharge. Hence, the DCIP data provides invaluable spatial information on the leachate characteristics, which cannot be obtained from boreholes alone