IN-SITU REMEDIATION OF CONTAMINATED HETEROGENEOUS SOILS

A process for the in-situ remediation of a contaminated heterogeneous soil region comprising: (a) introducing material for treating contaminants in a contaminated heterogeneous soil region into at least one liquid permeable region within the contaminated heterogeneous soil region to form at least one treating zone within the contaminated heterogeneous soil region, (b) transmitting direct electric current through at least one low permeability soil region within the contaminated heterogeneous soil region between a first electrode and a second electrode having opposite charge, wherein (i) the first electrode is located at a first end of the contaminated heterogeneous soil region and the second electrode is located at the opposite end of the contaminated heterogeneous soil region or (ii) the first electrode is located at a first end of each of the low permeability soil regions and the second electrode is located at the opposite end of each of the low permeability soil regions, (1) to cause an electroosmotic flow from the second electrode to the first electrode, (2) to cause an electromigratory movement of ionic contaminants in a direction toward the electrode of opposite charge, or (3) to cause an electroosmotic flow from the second electrode to the first electrode and an electromigratory movement of ionic contaminants in a direction toward the electrode of opposite charge, and (c) applying a hydraulic gradient across the contaminated heterogeneous soil region to cause a hydraulic flow from the high pressure end of the contaminated heterogeneous soil region to the low pressure end of the contaminated heterogeneous soil region.