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" 1 i 12 August 1996 AGE-NC Project No 95-0120 ' Page 3 of 4 ground water samples collected from MW-1 through MW-3 at concentrations of 92 Pg/1, 270 erg/l, ' and 130 ,ug/l, respectively z ' BTE&X and MTBE were not detected in any ground water samples collected in June 1996 The laboratory report (AAL Laboratory Batch No 96-0613-010-01 through 03) and chain-of-custody form are included in Appendix B i 4.0 CONCLUSIONS & RECOMMENDATIONS ' Ground water flow direction remained relativelyconstant at the site over the past two ears, flowing p Y g to the south to southeasterly direction Under that condition, monitoring well MW-1 is consistently ' located in an up-gradient location from the former UST area, while monitoring wells MW-2 and MW-3 are situated in the down-gradient position ' During this monitoring period,the ground water surface was between 0 88 feet and 144' feet above the top of screen intervals in monitoring wells MW-1 through MW-3 Typically, the sand filter pack of these ground water monitoring wells extend between 2 and 3 feet above the slotted interval Therefore, the analytical results of the samples are considered representative of the aquifer ' Based upon the low to moderate concentrations of hydrocarbon compound in the ground water over the monitoring periods since 1993,the concentration of hydrocarbon compounds leached from the vadose (soil) zone, reaching and impacting the water table appears to be relatively,minor The majority of the hydrocarbon-impacted soil was previously removed As hydrocarbons commonly are held by adsorption to clay and silt, most of the hydrocarbons remaining in the soil are probably adhering to the fine soilp articles and have little mobility ` We recommend further monitoring and sampling of the ground water monitoring wells for two ' periods If the monitoring results indicate that the hydrocarbon concentrations are decreasing and/or stable, a consideration for site closure is recommended 5.0. LIMITATIONS ' Our professional services were performed using that degree of care and skill ordinarily exercised by environmental consultants practicing in this or similar localities The findings were ibased upon analytical results provided by an independent laboratory Evaluations of the geologic/hydrogeologic ' conditions at the site for the purpose of this investigation are made from a limited number of available data points (i a monitoring wells) and subsurface conditions may vary away from these data points No other warranty, expressed or implied, is made as to the professional t