Enhanced biodegradation of TPH and PAHs in diesel contaminated soils through bioventing
A bioventing system was designed and installed to enhance the natural biodegradation of diesel fuel residuals in soils at an underground storage tank (UST) facility in Pittsburgh, Pennsylvania. This system was designed to operate in conjunction with a groundwater pump and treatment system which exposes the more heavily contaminated soils at the capillary fringe to ambient air supplied to the subsurface at a low flow rate from a single vertical injection point. Results of a pilot study conducted at the facility indicated that an initial average biodegradation rate of 2,100 milligrams of total petroleum hydrocarbons (TPH) per kilogram of soil per year could be achieved, making enhanced in situ biodegradation a feasible and cost-effective remedial alternative for soil cleanup. Oxygen (O{sub 2}), carbon dioxide (CO{sub 2}), and hydrocarbon vapor concentrations and pressure responses were measured in vapor monitoring points constructed at various depth intervals and varying distances from the central air injection point. Results indicate that the system is capable of providing sufficient oxygen to maintain microbial biodegradation of residual petroleum hydrocarbons within a radius of 70 feet of the injection point. Soil samples were collected during the installation of the vapor monitoring points and analyzed for TPH and PAH (Polynuclear Aromatic Hydrocarbon) concentrations to provide baseline analytical data from the areas of highest known contamination. A soil sampling program will be implemented to independently confirm the amount of TPH and PAH reduction that has occurred after the initial six-months of full-scale bioventing operation.
- OSTI ID:
- 215543
- Report Number(s):
- CONF-951139--
- Country of Publication:
- United States
- Language:
- English
Similar Records
Bioventing in the subarctic: Field scale implementation of soil heating to allow in situ vadose zone biodegradation throughout the year
Application of in situ bioventing in the remediation of deep soils at arid sites