
To address this question at a former dry-cleaning site in Jackson, Tennessee, scientists turned to advanced geophysical electrical resistivity imaging (ERI) to assess whether earlier cleanup efforts had successfully reduced DNAPL impacts, specifically trichloroethene (TCE) and tetrachloroethene (PCE). In the years leading up to the study, the site had undergone multiple remediations, including injections of corn syrup, vegetable oils, and Simple Green®, excavation of approximately 200 cubic yards of contaminated soil, and application of sodium lactate within the excavation zone
GeoTrax Survey™ technology, an enhanced, high resolution ERI tool, was employed for the assessment. The geophysical images revealed a striking patchwork underground: highly electrically conductive zones suggested bustling microbial activity where amendments were doing their work (purple zones in the image below) and highly electrically resistive spots flagged places where dense, undegraded DNAPL still clung to the subsurface matrix (orange zones in the below image).
By pairing these images with soil and groundwater data from targeted confirmation borings, the team created a detailed 3D picture of the site’s subsurface conditions, offering a smarter way to direct future remediation. In this case, GeoTrax Survey™ data told a story of both progress and persistence—showing exactly where nature’s cleanup crew was winning and where the contaminants were holding their ground.









