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3 � 19 July 2004 • AGE -NC -Project No 95-0121 Page 2 of 9 21 CPT LITHOLOGIC SOUNDINGS Soil bonngs CPT -1 through'CPT-4 were advanced vertically to total depths of 100 -feet bsg utilizing ' a 25 -ton truck -mounted CPT drill rig equipped with 2 -Inch diameter hollow -stem rods A hydraulic " ram was utilized to advance a cone penetrometer tip to total depth of each CPT boring Soil parameters such as cone penetrometer tip resistance, sleeve friction, friction ratio (ratio between ' sleeve friction 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 CPT drilling activities was containerized In properly labeled DOT- ' approved 55 -gallon drums, and stored on-site in an area lacking public access Soil borings utilized , -for soil and ground water sampling were backfilled by Inserting hollow steel rods to total depth of each boring and backfilling with a portland cement grout mix CPT soil borings were backfilled Iutilzmg a grout sleeve during rod removal, a portland cement/bentonite slurry was pumped through the grout sleeve during rod removal Instantaneously filling the void leis by the rods 22 SOIL DISTRIBUTION ' Based on the findings of CPT soil borings (CPT -1 through CPT -4) and of previous soil sample observations made from EW -1, MW -3, MW -4, MW -6, VW -1, VW -6 and VW -8, cross section AW " 1 was constructed and depicts the general lithology beneath the site (Figure 3) Although soil distribution may vary at each boring, AGE Interprets the CPT data collected from soil bonngs CPT -1 through CPT -4 to represent the typical soil types beneath the'site ' ' Generally, less permeable, silty clay and clayey silt with so-meJ fine sand was encountered from surface grade to depths of approximately 25 feet bsg, permeable, fine to medium sand was generally I observed at depths between 25 feet and 32 feet bsg, less permeable, silty clay and clayey silt was generally encountered at depths between 32 and 40 feet bsg Also, permeable to semi -permeable, fine sand/silty fine sand with some silt and clay was generally encountered at depths between 40 and 60 " feet bsg Lastly, less permeable clayey silt and silty clay with some fine' sand was generally encountered at depths between 60 feet and 100 feet bsg A significant layer of confining silty clay and clay was observed at 70 to 80 feet bsg, the layer appears to be continuous and was encountered throughout the site CPT computer generated boring logs are Included in Appendix B , Advanced GeoEnvironmental, Inc