HYDRAULICFRACTURESAS ANAEROBIC AND AEROBIC BIOLOGICAL TREATMENT ZONES

Hydraulic fractures were initially developed to be used in bedrock to enhance oil recovery. We have modified the procedure for use in the environmental field in shallower subsurface soils to increase the permeability of the soils to liquids, gases, and solids. This has allowed us to significantly enhance in situ methods of soil cleaning (pump and treat, steam injection, solvent extraction) (1) and aerobic bioremediation (2). We are now concentrating on enhancing movement of contaminants between hydraulic fractures and into hydraulic fractures using electrokinetics and destruction of contaminants within the hydraulic fractures. Bioremediation, very specific to the unusual conditions that electrokinetics presents to the subsurface soil is being developed. This work is being done as a result of the RTDF and in conjunction with researchers at Monsanto, Dupont, General Electric, and DOE. Hydraulic fracturing allows for the insertion of a pancake-shaped lens of sand. The sand lens increases the soil permeability of the area allowing a 10 fold increase in the area of influence of the well allowing for a 10 fold increase in vapor extraction, and a 10 fold increase in liquid addition (such as solubilized nutrients and hydrogen peroxide), which leads to a 100 fold increase in aerobic bioremediation (1). The process also allows for other solid addition to contaminated subsurface soil