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02 May 2008 AGE-NC Project No. 98-0440 Page 2 of 4 Soil Behavior Classification System(Robertson,P.K.,Campanella,R-G,Gillespie,D.and Greig,J., 1986), to generate a general stratigraphic and prepares a field CPT boring log (See Appendix A). Rinseate generated during drilling activities was containerized in properly labeled Department of Transportation(DOT)-approved 55-gallon drums and was stored on-site in an area lacking public access.All CPT soil borings were backfilled by inserting hollow rods to total depth of each boring and backfilling with a portland type H cement grout mix. 2.2. STRATIGRAPHY Based on the findings from soil boring CPT-1, clay and silty clay were encountered from surface grade to approximately 60 feet bsg and from 86 feet to 88 feet bsg. Sandy silt and clayey silt were encountered from 72 feet bsg to 86 feet bsg and from 88 feet bsg to 110 feet bsg. Sand and stiff fine- grained material were encountered from 60 feet bsg to 72 feet bsg.A computer-generated boring log of CPT-1 is included in Appendix A. 2.3. PORE PRESSURE DISSIPATION TESTING Pore pressure dissipation tests were taken at 58.56 feet bsg,61.84 feet bsg,and 110.07 feet bsg from soil boring CPT-1 to measure hydrostatic water pressures and approximate depth to ground water. The approximate depth to ground water was calculated using the following equation(Appendix B): Dw=D. -Hwa. where: DW=Depth to Ground Water(ft) D,C=Depth of CPT Tip Hwater=Hydrostatic Water Head(1 psi=2.31 ft) After 60 seconds,pore pressure stabilized at approximately 22.5 psi in the test performed at 61.84 feet bsg; depth to ground water was calculated at 37.03 feet. 2.4. CPT DRILLING AND GROUND WATER COLLECTION PROCEDURES A 25-ton truck-mounted CPT drill rig 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ram to advance to specified depths in each soil boring.A HydroPunch sample tool was pushed into the specified zone,then withdrawn approximately two to four feet to expose an inlet screen.The interior of the sampling tool filled with water and a V2-inch outer diameter stainless steel bailer was lowered and utilized to extract a ground water sample.Ground water samples were collected from 64 feet bsg to 69 feet bsg and from 75 feet Advanced GeoEnvironmentay Inc.