Detecting organic chemical contaminants by spectral-induced polarization method in glacial till environment

We present results that considerably extend the range of applications of spectral induced polarization (IP) measurements in surveying soil contaminated by organic chemicals. Soil/organic mixtures are polarizable even with very low contents of clay minerals, even though the use of spectral IP has so far been restricted to soils consisting predominantly of clay minerals.Laboratory measurements made on contaminated (toluene, heptane, ethylene glycol) and uncontaminated glacial till samples show that organic chemicals have a distinct effect on the phase spectra. Theoretical modeling further indicates that the phenomena measured in the laboratory are also relevant and detectable in field investigations.