The process for treating environmental contaminants in the soils located between the ground surface and the water table by inducing aerobic biodegradation. Air is introduced into the contaminated soils, providing oxygen for native soil bacteria to use in the biodegradation of organic compounds. The process is typically accomplished by extracting and/or injecting air from trenches or shallow wells which are screened within the unsaturated soils. The systems are similar to those used in vapor extraction. The main difference is that air extraction rates are low to minimize physical removal (stripping) of volatile organic compounds (VOCs) reducing the need for expensive treatment of the off-gases. The process may include the addition of nutrients such as common fertilizers, to provide nitrogen and phosphate for the bacteria. Bioventing is particularly attractive around buildings and actively used areas because it is relatively nonintrusive and results in minimal disturbance during installation and operation. The process is most suitable for petroleum hydrocarbon blends such as gasoline, jet fuel, and diesel oil, for petroleum distillates such as toluene, and for nonchlorinated solvents.

See Also

Biodegradable; Bioremediation; Vapor Recovery System