Combining in situ technologies in low-permeability soil, a case study
- Bechtel National, Inc., San Diego, CA (United States)
- OHM Remediation Services Corp., San Diego, CA (United States)
- Kleinfelder, Inc., Diamond Bar, CA (United States)
- NAVFACENGCOM SWDIV, San Diego, CA (United States)
Three in situ technologies (multiphase extraction, pneumatic soil fracturing, and bioremediation) were used to remediate fine-grained soil and groundwater contaminated with jet fuel and gasoline at a fuel farm at the Naval Air Facility, El Centro, California. Soil contained petroleum hydrocarbon concentrations up to 600,000 mg/kg (saturated), and monitoring wells indicated an apparent free-product thickness up to 2.1 m. The site soils are characterized by a 3.6- to 4.6-m clay layer overlying a 0.6- to 1.2-m silty sand layer. The hydrocarbons were predominantly present in the clay from 2.4 to 4.6 m below grade, with the highest concentrations found within vertical or inclined fractures interpreted to be former desiccation cracks. Estimated costs to excavate, transport, thermally treat, and replace the soil at the fuel farm were prohibitive because they would involve closing, dismantling, and reassembling the fuel farm. The use of fluid injection with vacuum extraction (FIVE) was proposed as an alternative of treating the site soils without disrupting the fuel farm operations at approximately one-half of the original cost. A pilot test was conducted to assess the effectiveness of the system and calculate well and pneumatic fracture point spacing. The full-scale remediation system consisted of 122 extraction wells, a 115-m horizontal well, and 300 pneumatic fracture points over an area of approximately 300 by 180 m.
- OSTI ID:
- 567810
- Report Number(s):
- CONF-971032--
- Country of Publication:
- United States
- Language:
- English
Similar Records
Steam injection vacuum extraction technology demonstration, Naval Air Station, Lemoore, California
Potential of pneumatic fracturing to enhance in situ remediation technologies