Low-intensity Bioventing for Remediation of a JP-4 Fuel Spill at Site 280, Hill Air Force Base, Ogden, Utah

Site Name:

Hill Air Force Base

Location:

Ogden, Utah

Period of
Operation:

Status - Ongoing
Report covers - 12/90 to 6/94

Cleanup
Type:

Full-scale cleanup (interim results)

Vendor:

Not Available

Technology:
Bioventing - System consists of 1 injection well and 10 monitoring wells - Air flow rate on blower discharge ranged from 20 to 117 acfm; operated since 11/93 at 20 acfm - Blower discharge pressure of 2 in. of Hg

Cleanup Authority:
State: Utah

SIC Code:
9711 (National Security)
Point of Contact:
William James
Remedial Project Manager
Hill Air Force Base
Ogden, Utah

Contaminants:
Total Petroleum Hydrocarbons (TPH) and Benzene, Toluene, Ethylbenzene, Xylenes (BTEX) - Soil TPH concentrations measured as high as 5,040 mg/kg - Soil gas TPH concentrations measured as high as 11,200 ppm

Waste Source:
Spills and other releases of JP-4 jet fuel

Type/Quantity of Media Treated:
Soil - Soil-gas permeability value - 0.057 darcy - Porosity 30 to 50%; moisture content 1.4 to 18%; air conductivity 4.7 to 7.8 darcies; particle density 0.3 to 0.5 gm/cm[Sup 3] and particle diameter 0.8 to 10 mm; soil bulk density 0.37 to 0.48 gm/cm[Sup 3]; soil organic content 0.08 to 0.86%

Purpose/Significance of Application:
Bioventing to remediate soils contaminated with JP-4 jet fuel.

Regulatory Requirements/Cleanup Goals:
No specific cleanup goals established at this time - Cleanup assessment will be conducted subject to "Guidelines for Estimating Numeric Cleanup Levels for Petroleum Contaminated Soils at Underground Storage Tank Release Sites," which are established by Utah Department of Health

Results:
Bioventing project was not complete at time of this report - Respiration rate tests from 4/91 to 11/93 indicate hydrocarbon degradation is occurring - As of 11/92, soil gas TPH concentration reduced to less than or equal to 2,600 ppm - Estimates of the mass of contaminants removed have not yet been reported

Cost Factors:
Total Capital Cost (estimated) - $115,000 (including construction of piping system, buildings, process equipment, and startup) - Total Annual Operating Cost (estimated over 4 years) - $24,000 (including labor, electricity, lab charges, maintenance, and monitoring)

Description:
As a result of spills and other releases of JP-4 jet fuel at the 280 Fuel Storage Lot at Hill Air Force Base in Ogden, Utah, soil was contaminated with total petroleum hydrocarbons (TPH) and benzene, toluene, ethylbenzene, and xylenes (BTEX). TPH concentrations were reported as high as 5,000 mg/kg in the soil and 11,200 ppm in the soil gas. A low-intensity bioventing system was installed at the site and has been in operation since December 1990. No specific cleanup goals have been established at this time. The final cleanup assessment will be conducted subject to "Guidelines for Estimating Numeric Cleanup Levels for Petroleum Contaminated Soils at Underground Storage Tank Release Sites", which are established by the Utah Department of Health.

The bioventing system includes one injection well (100 ft. depth) and 10 monitoring wells (varying depths). During the operation of this system, the air flow rate of the blower discharge had been varied between 20 and 117 acfm (at a discharge pressure of 2 in. of Hg) in order to optimize air flow rates while eliminating volatilization. Available data from respiration rate tests (4/91 to 11/93) indicate that hydrocarbon degradation is occurring. As of November, 1992, soil gas TPH concentrations had been reduced from 11,200 mg/kg to below 2,600 mg/kg. Estimates of the mass of contaminants removed have not yet been reported.

The estimated total capital cost for this application is $115,000. The total annual operating cost, estimated over 4 years, is $24,000 exclusive of final site characterization. During this application, it was noted that biodegradation is enhanced by maintaining adequate soil oxygen, moisture, and nutrient levels and that estimates of biodegradation are more accurate if oxygen depletion is used instead of carbon dioxide formation. In addition, it was noted that air flow rates can be optimized to low levels ranging from 40 to 67 acfm.