Soil excavation and landfarming were the selected remediation and in June 2003, the soil vapor extraction system was decommissioned and CEG was contracted by the Maine DEP to supervise the excavation of the petroleum-impacted soil for landfarming. A total of 4,500 cubic yards of petroleum-impacted soil, was removed and transported to a Maine DEP approved landfarm site. The soil was mixed with compost and spread to a maximum thickness of 5 inches, in accordance to Maine DEP's landfarm guidelines. The landfarm soil was rototilled, monitored for volatile organic compounds, and sampled for gasoline range organics according to a Maine DEP approved schedule. Within 6-months of landfarming the soil, the soil was below the Maine DEP cleanup goal of 25 mg/kg for gasoline range organics in soil.
Based on these results and ongoing aeration of the landfarmed soil, CEG recommended site closure of the site, which was approved by the Maine DEP.
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