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I ' 20 January 2005 . AGE-NC Project No 04-1045 ' Page 4 of 7 ' Monitoring wells MW-1 through MW-3 were developed utilizing a Waterra inertia pump with a hose bailer Ground water was purged from each monitoring well until ground water was visually sediment free, approximately 13 to 20 gallons of water were removed from each well During ' development, Ground water temperature, pH and conductivity were measured at regular intervals during purging using an Oakton water analyzer Purged water was stored on-site in properly labeled, 55-gallon DOT-approved drums Field sheets and data are included in Appendix C 2 2 2 Collection and Analysis of Ground Water Samples Water samples were collected from each purged well using a disposable plastic bailer after allowing the wells to achieve a minimum 80%recovery of the pre-purge water volume Each water sample was transferred into three laboratory-supplied 40-ml volatile organic analysis(VOA)vials containing 0 5 ml of hydrochloric acid as preservative and one 1-liter amber bottle After collection,the samples were properly labeled,placed in a chilled container and transported under chain of custody to CTEL for analysis The samples were analyzed for '. • TPH-g and total petroleum hydrocarbons quantified as diesel (TPH-d) in accordance with EPA Method 8015M, • BTEX and MTBE in accordance with EPA Method 8260B, and ' • Fuel additives in accordance with EPA Method 8260B I3.0. FINDINGS IGround water elevation, flow direction, and gradient were determined from field data collected on 24 November 2004 The contaminant impact to soil and ground water was quantified from the laboratory analytical data I31 STRATIGRAPHY Generally, an orange brown to light brown, moist, clayey silt to silty clay was encountered from I surface grade to approximately 25 feet bsg, and brown to gray, moist, sandy silts and sands were encountered from approximately 25 feet to 35 feet bsg Geotechnical analysis determined that • The soil sample collected from MW2 at 20 feet bsg(MW2-20) is a brown clayey sand with a porosity of 34 5%, an average permeability of 5 Ox 10-8 cm/sec and a specific gravity of 2 73 centimeters per second(cm/sec),the hydraulic conductivity ranged from 3 5 x 10-'cm/sec IAdvanced CeoEnvironmental,Inc