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I07 September 2005 i AGE-NC Project No 98-0540 ' Page 5 of 9 ' monitoring wells MW-1 through MW-5 relative to the tops of the well casings The ground water elevations and gradient were determined from this data (Table 1) I After depth to ground water measurements were collected, approximately 6 to 9 gallons of water(a minimum of three casing water volumes per well) were purged from wells MW-1 through MW-5 using a Waterra inertia pump and dedicated tubing Ground water temperature,pH,and conductivity ' were measured for stability at regular intervals during the purge process using an Oakton water analyzer Field data sheets are Included in Appendix E Purged ground water was containerized in properly labeled, DOT-approved 55-gallon drums and stored on-site 2 3 2 Collection and Analysis of Ground Water Samples Ground water samples were collected from each purged well using the Waterra Inertia pump and dedicated tubing Each water sample was transferred Into three laboratory-supplied, 40-m1 VOA vials containing 0 5 ml 18% hydrochloric acid solution as a sample preservative At the request of the EHD, ground water samples from on-site domestic well DW-1 and off-site domestic wells DW-2 through DW-5, were also collected and analyzed To ensure that formation water was being produced, water was allowed to run out of the well for approximately 10 minutes, I which was long enough to automatically turn on the well pump Ground water was poured directly Into the 40-m1 VOA vials from a valve at the well heads Locations of domestic wells are Illustrated on Figure 3 ' After collection, all ground water samples were properly labeled, placed in a chilled container, and transported under chain of custody to CTEL for analysis for the constituents listed in Section 2 12 3.0. FINDINGS The computer-generated CPT lrthologic log and soil descriptions from the monitoring well installations were integrated with previous subsurface soil descriptions to construct geologic cross- sections A-A'and 13-13'(Figures 4 and 5,respectively) The hydrocarbon impact to groundwater and soil was quantified by laboratory analysis of the ground water and soil samples 31 STRATIGRAPHY IGenerally,alternating layers of clayey soil(clayey silt, silty clay, clay,and sandy clay)and silty and • sandy soil (silt, sandy silt, silty sand, sand, and clayey sand) were encountered in borings CPT-1, MW-4, and MW-5 to approximately 95 feet bsg In boring CPT-1, stiff, fine-grained material and Advanced GeoEnvironmental,Inc.