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' Mr Harlan Knoll <br /> September 20, 1993 <br /> Page 3 <br />' recent basin deposits of the Great Valley Sequence Near-surface sediments include <br /> interbedded sands, silts, below grade clays and gravels Groundwater is present beneath <br /> the site at approximately 40 ft below grade and is inferred to flow in a northeasterly <br />' direction <br />' SCOPE OF WORK <br /> Further evaluation of the extent of soil and groundwater contamination along the <br />' western border of the site is required to evaluate appropriate soil and groundwater <br /> remedial options We propose a subsurface environmental investigation which will include <br />' drilling three soil borings and installing monitoring wells in two of those borings The first <br /> boring/well will be drilled and installed adjacent to the diesel excavation near the western <br /> edge of the former center tank location The second bonng/well will be drilled and <br />' installed near the eastern property boundary near a former pump island The third boring <br /> will be angle-dnlled beneath the sidewalk on the western property boundary near the <br />' former central diesel tank and pump islands Soil samples will be selected from each <br /> boring for laboratory analysis <br /> The boring locations have been selected to provide representative samples in the <br /> assumed downgradient and crossgradient directions of groundwater flow Groundwater is <br /> Iinferred to be approximately 40 ft below ground surface and flow is inferred to be <br /> northeasterly Because of local irregularities in the groundwater surface, groundwater <br /> flow direction beneath the site may vary from this general direction and additional wells <br /> may be required <br /> Soil Borings <br /> The borings will be drilled by a licensed well-driller using a drilling rig equipped <br /> with 8-in hollow-stem augers Soil samples will be collected at maximum 5-ft intervals <br />' and/or at lithologic changes in all borings using a California-modified split-spoon sampler <br /> containing clean stainless steel sleeves Soils will be logged as encountered in the borings <br /> and a photoionizing organic vapor meter (OVM) will be used during sampling to detect <br /> Ipotential hydrocarbon concentrations in the soil samples Drilling operations will be <br /> conducted under the direction of a qualified environmental geologist Drill cuttings will be <br /> placed on and covered with plastic sheeting and Ieft onsite Proper disposal of the drill <br /> ROGER <br /> I 323-001 ww FQDT T <br /> ASSOCIATES <br />