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23 March 2001 <br /> • AGE-NC Project No 95-0130 <br />' Page 2 of 6 <br />' 21 CPT LITHOLOGIC SOUNDINGS <br /> Soil borings P-10, P-11 and P-12 were advanced vertically to total depths of approximately 120 feet <br />' bsg utilizing a 25-ton truck-mounted CPT drill rig equipped with 2-inch diameter hollow-stem rods <br /> A hydraulic ram was utilized to advance a cone penetrometer tip to total depth of each CPT boring <br /> Soil parameters such as cone penetrometer tip resistance, sleeve friction, friction ratio (ratio between <br />' sleeve friction and tip resistance) and pore water pressure were continuously measured as the cone <br /> penetrometer was advanced to depth A continuous boring log was generated utilizing the <br /> Hogentogler Co CPT computer program The Hogentogler Co computer program utilized the CPT <br />' Soil Behavior Classification System (Robertson, P K , Campanella, R G, Gillespie, D and Greig, J , <br /> 1986), to generate a general lithology type and display on CPT boring logs (See Appendix A) <br /> Rinseate generated during drilling activities was containerized in properly labeled DOT-approved <br />' <br /> 55-gallon drums, and stored on-site in an area lacking public access All soil borings were backfilled <br /> by inserting hollow rods to total depth of each boring and backfilling with a portland cement grout <br /> mix <br />' • 2 2 STRATIGRAPHY <br /> Based on the findings from CPT soil bonngs P-10, P-I1 and P-12, cross sections D-D' and E-E' <br /> were constructed to depict general lithology beneath the site (Figures 3 and 4) Generally, gravelly, <br /> fine to coarse sand layers were observed at depths between 35 and 47 feet bsg, 62 and 65 feet bsg, <br /> 90 and 108 feet bsg and 116 feet bsg to total depth Generally, fine grained, silty clay and clayey silt <br />' layers were encountered at depths between 25 and 30 feet bsg, 64 and 70 feet bsg, 80 and 85 feet bsg <br /> and between 106 feet and 112 feet bsg Variable lithology including silty fine sand, sandy silt and <br /> clayey silt to silty clay were observed at all other depths CPT computer generated boring logs are <br />' included in Appendix A, geologic cross sections D-D' and E-E' were generated from CPT data <br /> collected at P-10, P-I 1 and P-12 and depict general lithology beneath the site in cross sectional view <br /> (Figures 3 and 4, respectively) <br /> 1 <br /> 23 CPT DRILLING AND GROUND WATER COLLECTION PROCEDURES <br />' A 25-ton truck-mounted CPT drill rig equipped with 2-inch diameter hollow-stem rods fitted with <br /> a HydroPunch ground water sampling tool utilized a hydraulic ram to advance to specified depths <br />' in each soil boring A HydroPunch sample tool was pushed into the specified zone, then withdrawn <br /> approximately three feet to expose an inlet screen The interior of the sampling tool filled with water <br /> and a 1/z-inch outer diameter(O D )stainless steel bailer was lowered and utilized to extract a ground <br />' water sample Ground water samples were collected from each selected depth interval (zone) based <br /> • on previously acquired CPT-lithology data indicating favorable conditions for sampling ground <br /> IAdvanced GeoEnvironmental,Inc <br /> I <br />