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Soil Remediation The soil remediation process will encompass the following steps • Excavation, • Excavation confirmation sampling, • Excavation backfilling, and • Transportation and disposal at a Class II landfill These steps are described in more detail below Excavation Affected soils from Site #2 will be excavated and transported to a Class II landfill Because the maximum depth of the affected soil is predicted to be no greater than 11 feet bgs, excavation will be conducted with conventional excavation equipment (backhoes) The excavation sidewalls will be sloped at a 21 slope If affected soil extends below the water table, an attempt will be made to remove these affected soils Because the ground water horizon is located within the clay/silt layer, it is anticipated that the first several feet will be dry enough to excavate Near the clay/slit layer and sand layer interface, the soil will most likely be much too wet to excavate, due to lack of ' cohesion and expected sloughing Based on previous investigations, the extent of the affected soil is expected ' to be minor (approximately 210 cubic yards) The goal of the remediation is to remove the majority of TPH-affected soils containing more than 100 mg/kg TPH as gasoline, or 10 mg/kg total BTEX compounds Based on previous experience at the site, TPH-impacted soils are readily apparent by visual and other field observations ERM will use this visual evidence and measurements from a direct-reading instrument such as a Flame Ionizing Detector (FID) to identify the appropriate excavation boundaries and to segregate non-impacted from impacted soils Stockpiles that appear to consist of non-impacted soils will be sampled to confirm that TPH and BTEX concentrations are below action levels, and will be used as backfill in the excavated areas Stockpiles consisting of impacted soils will be sampled and analyzed for profiling purposes 5-2