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' 23 May 2003 AGE-NC Project No 95-0184 ' Page 2 of 9 ' 21 CPT LITHOLOGIC INVESTIGATION The CPT investigation utilized a 20-ton truck-mounted CPT dnll ng equipped with 1 50-inch ' diameter h ollow-stem rods A h ydraulic ram w as utilized to advance a c one p enetrometer tip attached to the hollow-stem rod assembly to total depth of each soil boring Soil borings were advanced vertically to the following total depths at the specified locations ' • CPT-2 was advanced to 100 feet below surface grade (bsg) at the former diesel UST excavation, the twin soil boring was advanced to 157 feet bsg to collect water samples ' • CPT-3 was advanced to 176 feet bsg approximately 100 feet east of CPT-2, the twin soil boring was advanced to 180 feet bsg to collect water samples CPT-3 was terminated at the above-mentioned depths due to refusal encountered during drilling activities At each boring location,the soil parameters of cone penetrometer tip resistance, sleeve friction and ' pore water pressure were continuously measured as the cone penetrometer was advanced to depth Utilizing the soil parameters, the Hogentogler Co computer program interpreted general lithology types based on the CPT Soil Behavior Classification System (Robertson, P K , Campanella, R G, 10 Gillespie, D, and Greig, J , 1986) and displayed the interpreted lithologies on a continuous CPT boring log The CPT interpretive logs are presented in Appendix A ' Rmseate generated during drilling activities was contamenzed in properly labeled DOT-approved 55-gallon drums and was stored on-site in an area lacking public access The CPT soil borings were backfilled over their entire depth range with a bentonite/portland cement grout mix I 2 2 GROUND WATER SAMPLE COLLECTION Following advancement of the initial bonng to collect lithologic data, a HydroPunch ground water I sampling tool was attached to the hollow-stem rod assembly and utilized to collect grab ground water samples at specified depths from an immediately adjacent,twin soil boring The ground water samples were collected at selected depths based on the previously acquired CPT hthologic log indicating favorable conditions for sampling ground water The HydroPunch sample tool was pushed into the specific depth interval, then withdrawn approximately five feet to expose an inlet screen The interior of the sampling tool fills with water and a 1-inch outer diameter (O D ) stainless steel bailer was lowered and utilized to extract a ground water sample Ground water sample was collected from the CPT borings at the following intervals • CPT-2 was sampled at 72 to 76 feet, 82 to 86 feet, 92 to 96 feet, 112 to 116 feet, 143 to . 147 feet and 153 to 157 feet bsg, and IAdvanced GeoEnvironmenta[,Inc