Technology:
Air Sparging and Soil Vapor Extraction (AS/SVE)
- Equipment included 23 air injection wells, 10 extraction wells, and 5 French drains
- Air was pumped into the aquifer through the injection wells, and removed as soil vapor from the extraction wells and French drains
- The air sparge system operated at 15 cfm from December 1997 to February 1998, and then shut down due to screen fouling
- The SVE system removed soil gas at rates ranging from 475 to 625 scfm, and operated at a relatively high vacuum (13 inches Hg)
- Extracted vapors were treated with carbon prior to release to the atmosphere
Type/Quantity of Media Treated:
Soil and Groundwater
- Bedrock at the site is overlain by 15-20 ft of glacial outwash materials, primarily gravel and sandy gravel; the aquifer is contained in the outwash materials, varies from 0 - 40 ft thick, and is relatively free of fine-grained till layers
- Hydraulic gradients are nearly flat
- A surficial deposit ranging from 24 - 31 ft thick, composed of glacial till and artificial fill, caps the site - the till and fill are silty clay to sandy clay
- Vadose zone contamination occurs at a depth of less than 20 ft.
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