Geophysical Detection of Perchloroethylene in a Sandy Aquifer Using Resistivity and Nuclear Logging Techniques

The Effects of LNAPL Biodegradation Products on Electrical Conductivity Measurements

“…This "insulating layer" model has been verified in shortterm laboratory and controlled spill experiments (Schneider and Greenhouse, 1992). However, investigations at numer-ous sites with aged contamination show that the LNAPL smear zone has a lower resistivity (higher conductivity) than the bulk formation (Atekwana et al, , 1999Benson and Stubben, 1995;Gajdos and Krai, 1995;Sauck, 1998).…”

A borehole geophysical method for detection and quantification of dense, non-aqueous phase liquids (DNAPL) in saturated soils

“…Schneider and Greenhouse (1992) and Endres and Greenhouse (1996) note that DNAPL strongly attenuate the signal from a borehole thermal neutron log through neutron capture by the chlorine atoms in the chlorinated hydrocarbons. Zones of anomalously low neutron response may be associated with DNAPL concentrations.…”

The relationship of total dissolved solids measurements to bulk electrical conductivity in an aquifer contaminated with hydrocarbon

“…Until recently, it has commonly been assumed that hydrocarbon-impacted sediments can be effectively imaged only by their higher resistivities compared to bbackgroundQ due to the partial replacement of conductive soil and pore water by highly resistive petroleum compounds (e.g., Mazác et al, 1990;Schneider and Greenhouse, 1992;De Ryck et al, 1993). This premise is correct as long as the hydrocarbon is fresh, or has not been physically, chemically, or biologically altered.…”