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7 : 19 June 2000 iAGE-NC Project No 96-0232 Page 12 of 35 4.0. SOIL CHARACTERIZATION On 15 May 2000, three soil samples (P21-20, P25-15 and P27-20) were submitted for laboratory analysis of porosity, moisture and density Porosity of P21-20 was measured at 37 8 percent, moisture at 212 percent and the soil was characterized as a sandy clay Sample P25-15 had 37 8 percent porosity, 22 6 percent moisture, and was a sandy clay Analysis of P27-20 measured a porosity of 34 9 percent,moisture content of 19 8 percent,and classified the soil type as a sandy clay Copies of the laboratory reports are in Appendix F On 28,29 and 30 March 2000, CPT soil borings P13, P14, P15,P16 and P17 were advanced on and off-site(see Figures 3)to characterize the geological and hydro-geological framework and to assess potential migration pathways 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 a cone penetrometer was advanced to depth A continuous boring log was generated utilizing a 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 continuous log of lithology types(See Appendix B) Based on the lithology logs generated from CPT soil borings P13, P14, P15, P16 and P17, cross sections C-C,D-D'and E-E'were generated to depict general lithology beneath the site(see Figures 21, 22 and 23) Gravelly, fine to coarse sand generally was logged between 35 and 50 feet bsg, between 70 and 75 feet bsg and between 85 and 115 feet bsg, silty clay and clayey silt generally were logged between 15 and 35 feet bsg, between 60 and 80 feet and between 115 and 120 feet bsg 5.0. AQUIFER STEP DRAW-DOWN PUMP TEST On 14 March 2000, an aquifer step draw-down pump test (pump test) was performed at the site to evaluate general ground water aquifer characteristics and to evaluate ground water draw-down at various pumping rates The pump test consisted of extracting ground water from well MW-1 utilizing a 2-inch diameter Grundfos Redi-flo pump The first stage of the pump test consisted of pumping ground water at a rate of 3 GPM,the second stage of the pump test consisted of pumping ground water at a rate of 3 5 GPM, the third stage of the pump test consisted of pumping ground water at a rate of 3 GPM The pump test utilized pressure transducers that were deployed in well MW-1 at a depth of 18 5 feet bsg and in wells MW-2, MW-4 and MW-6A at a depth of 14 5 feet bsg Draw-down versus time for well MW-1 was graphed on semi-logarithmic paper for stages 1, 2 and 3 of the pump test, utilizing the Jacob straight-line method, the transmissivity for each stage of the pump test was determined (Appendix G) Ground water levels from wells MW-2, MW-4 and MW- 6A did not appear to be influenced during the pump test Advanced GcoEm ironmental,Inc