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sample was collected using a disposable plastic bailer The sample was collected in three 40 <br /> ml EPA vials <br /> 3.5 Monitoring Well Surveying <br /> On November 1, 1993, the casing elevation of the new monitoring well (MW-4) was <br /> surveyed relative to monitoring wells MW-1, MW-2 and MW-3 <br /> 3.6 Laboratory Analysis of Soil and Water Samples <br /> Selected soil samples were analyzed for total petroleum hydrocarbons (TPH as gasoline) <br /> and volatile aromatics (BTE&X) in accordance with EPA methods 8015m and 8020, <br /> respectively <br /> The water sample was analyzed for TPH as gasoline and BTE&X in accordance with EPA <br /> methods 8015m and 602, respectively <br /> 4 0 FINDINGS <br /> 4.1 Stratigraphy <br /> The stratigraphy appears to be relatively uniform across this site All four wells penetrated <br /> three distinct units Clayey silt to silty clay is pi esent from the surface to 26 feet in depth <br /> The silt overlies medium-grained sand that extends to approximately 32 feet Blue-green to <br /> olive gray silty clay is present from 32 feet to the bottom of the borings (50 feet, see <br /> Appendix A) <br /> 4.2 Relative Groundwater Elevation and Gradient <br /> IBefore drjlhng was initiated, groundwater depths were measured in MW-1 through MW-3 <br /> on October 11, 1993, to confirm groundwater flow direction The flow direction was <br /> determined to be northeast <br /> On October 19, 1993, the gradient was calculated to be 0 00057 directed N 66° E (Figure <br /> 3) This gradient is moi a shallow than the previous measurement of 0 004 ft/ft directed N <br /> 38° E in November 1992 Table 2 summarizes the groundwater depth and elevation data <br /> 4.3 Field and Laboratory Evidence of Contamination <br /> Hydrocarbon odors were noted in soil samples from 35 to 50 feet in MW-4 Volatile organic <br /> vapors were measured in samples from 40 to 50 feet at levels to 16 ppm <br /> 6 <br />