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' .. 24 July2001, . • • ' ' , .- ,•- ' ,J 1 • AGE-NC Pro'ect No. 98-0440 ' 1'P age 3 of4"", The ground water.flow direction was inferred using ground water elevation data. The,ground water at the site on 25 ,June 2001 was inferred to have been flowing to the north-northwest:under an average hydraulic.gradient of 0.009,feet/feet..Figure 4 illustrates the ground water elevation contours. `.3.2. ANALYTICAL RESULTS OF GROUND WATER SAMPLES " ' TPH-g w detected in the water les collected from monitoring wells MW2 and MW5 at . . as d, samples conceritrations-of 120 micrograms per liter,(ug/l) and 95 µg/1,respectively.'TPH-d was not detected . '"at or.above laboratory''reporting limits in.the water samples. Qne or'more BTEX,compound's were detected in the.water-samples collected'from wells MW2, '. 'MW5 and MW6 at'concentrations as ;high as- 12 µg/1 benzene, 0.59 µgll toluene,, 8' µg11, ethylbenzene and 4:3 µgh total xylenes. MTBE-was not detected at or-above laboratory,reporting s_ limits in the ground water samples: No analytes were detected at or above laboratory'reportirig limits in the water samples collected from domestic wells DW5157 and DW5055. ' 11 _Current and previous analytical results'are summarized on Table 2. The laboratory report (MAI Lab ID No. 68651; 68652 and.71062 through 71067), QA/QC report and chain-of-custody forrh are included,in' Appendix B. n . CONCI;USIONS 4.0. SUMMARY AND Based on the data collected during this monitoring period;AGE.concludes: On.. 25 June',.2001; the ground water at the' site was inferred .to be flowing .to the ' north-northwest under an average gradient of 0.009 feet/feet'. ..The. highest 'concentration',of dissolved hydrocarbons quantified as TPH=g and BTEX compounds;extends north.frorn USTs No:4 and 5.Dissolved hydrocarbons were encountered' ' in the down-gradient;direction from the former USTs in samples frorri monitoring wells MW2 and MW5: ,Dissolved petroleum hydrocarbon concentrations decreased in water samples from wells MW1, MW2, MW5 and'MW6: Dissoived•hydrocarbons decreased to, non-detectable concentrations in . wells MW1 and- MW6. ' Dissolved hydrocarbon ' concentrations remained,non-detectable in samples from wells MW3 and MW4. ` ddvunced GeoEnvironmental,Inc.