Geophysical identification of leachate levels and refuse characterization in a landfill at Argonne National Laboratory, Illinois

摘要

Magnetic and electrical geophysical techniques were used to survey the 800 Area landfill at Argonne National Laboratory as part of an environmental site assessment. This landfill was opened in 1966 and has accepted non-radioactive laboratory, office, food service and construction wastes. Magnetic profiles and electrical resistivity surveys using Wenner, Schlumberger and dipole-dipole arrays were made primarily over the northern portion of the landfill and long its margins. Mounding of leachate to within 5 ft. (1.5 m) of the surface was identified within the north-central and northeastern portions of the landfill using resistivity soundings and dipole-dipole surveys. Soundings also suggest refuse thickness varies from 10--30 ft (3--10 m) south to north across the landfill. Both dipole-dipole and magnetic profiles have identified conductive and insulating objects in the refuse. Areas of low resistivity flanking the northeastern and eastern margins of the landfill may represent migration of leachate to the north and east. High resistivity layers detected beneath the landfill suggest little or no downward percolation of mineralized leachate. Such high resistivity layers, however, may indicate the presence of sand and gravel layers/lenses embedded in the drift which are potential contaminant pathways. The geophysical results are presently being used in optimum placement of monitoring wells, soil gas probes and future remediation planning. 5 refs., 6 figs.