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I 31 July 2000 AGE-NC Project No 95-0130 IPage 2 of 9 ' 2 1 CPT LITHOLOGIC SOUNDINGS Soil bonngs CPT-1, CPT-1A, CPT-2, CPT-2A and CPT3 were advanced vertically to maximum ' depths of 105 feet bsg utilizing a 25-ton truck-mounted CPT drill ng equipped with 2-inch diameter hollow-stem rods (See Figure 2) Each CPT soil boring utilized a hydraulic ram to advance a cone penetrometer tip to total depth of each soil boring Soil parameters such as cone penetrometer tip resistance, sleeve friction, friction ratio (ratio between sleeve fraction and tip resistance) and pore water pressure were continuously measured as the cone penetrometer was advanced to depth A continuous boring log was generated utilizing the Hogentogler Co CPT computer program The Hogentogler Co computer program utilized the CPT Soil Behavior Classification System (Robertson,P K,Campanella,R G,Gillespie, D and Greig,J , 1986),to generate a general lithology type and display on a CPT boring log(See Appendix A) Rinseate generated during drilling activities ' was containerized in properly labeled DOT-approved 55-gallon drums, and stored on-site in an area lacking public access All soil borings were backfilled over their entire depth with a portland cement grout mix Drilling refusal was encountered at soil borings CPT-1 and CPT-2 at depths of 76 and 70 feet bsg, respectively Therefore, replacement soil bonngs CPT-IA and CPT-2A were advanced at the site to maximum depths of 105 feet bsg 22 STRATIGRAPHY Based on the findings from CPT soil bonngs CPT-1, CPT-1A, CPT-2, CPT-2A and CPT3, cross sections A-A' and B-B' were constructed and depict general lithology beneath the site(Figures 3 and 4) Generally, a gravelly, fine to coarse sand layer was observed at depths between 85 and 90 feet bsg, silty fine sand was observed at depths between 12 and 23 feet bsg, and between 55 feet and 65 feet bsg, silty clay and clayey silt were observed between 1 and 12 feet bsg, between 23 and 43 feet bsg and between 77 and 120 feet bsg Variable lithology including silty fine sand, sandy silt and clayey silt to silty clay was observed at all other depths CPT computer generated boring logs are included in Appendix A 23 CPT DRILLING AND GROUND WATER COLLECTION PROCEDURES A 25-ton truck-mounted CPT drill ng equipped with 2-inch diameter hollow-stem rods fitted with a HydroPunch ground water sampling tool utilized a hydraulic ram to advance to specified depths in each soil boring A HydroPunch sample tool was pushed Into the specified zone, then withdrawn approximately four feet to expose an inlet screen The interior of the sampling tool filled with water and a 1-inch outer diameter(O D ) stainless steel bailer was lowered and utilized to extract a ground Advanced GeoEnvi ron mental,Inc