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1 - ' 30 June 2003 AGE-NC Project No 98-0433 ' Page 3 of 4 ' The ground water elevation in wells MW-6 Increased 0 63 feet since the previous monitoring event, somewhat due to the free phase product Depth to ground water and calculated elevation date are presented In Table 1 ' Ground water flow direction and gradient were calculated from the May 2003 gauging data Ground water flow was Inferred to be toward the northwest at wel1SMW�l, - s figure 3) �MW-1) -2 3 �1�1 9 '9 r ` 0-p 00, v��sl°y 32 ANALYTICAL RESULTS OF GROUND WATER SAMPLES Cynn 9 , TPH-g was detected In the ground water samples collected from MW-1 MW-2,MW-6 and MW'All ' at concentrations ranging from micrograms per liter 1,700(�Ig/l) (MW-36to 180,000 EIg/1 (MW-1) TPH-d was detected In the ground water samples collected from wells MW-1 and MW-6 at ' concentrations of 250 milligram per liter (mg/1) and 7 6 mg/l, respectively One or more BTEX compound were detected In samples MW-1,-#A*A-20and MW-6, the maximum, lie concentrations were 270µg/1 benzene(MW-1),3 80 p,g/1 ethylbenzene(MW-1)and 790 ug/l xylenes (MW-1) MTBE was detected by EPA method 8260 In samples MW-1, MW-8 and MW-9 at concentrations of 1,100 gg/l, 49 }Ig/1 and 3,000 gg/l, respectively TAME were detected in sample ' MW-9 at 33 gg/l Target analytes were not detected at or above laboratory reporting limits In the water sample collected from the domestic well (DW-1) on-site ' Analytical results from ground water samples are summarized In Table 2 The laboratory report (CalTech ID CT214-0305086),quality assurance and qualltycontrol(QA/QC)and chain-of-custody are Included In Appendix B The distribution of dissolved hydrocarbons Is depicted in Figure 4 ' 4.0. SUMMARY AND CONCLUSIONS Based upon the data collected during the May 2003 monitoring event, AGE concludes ' Ground water at the site was encountered at approximately 23 to 25 feet below the casing tops The prevailing ground water flow direction from the former UST area was generally AV� toward the northwest at a gradient of 0 004 ft/ft ' �� • The highest concentration of TPH-g was In the area of monitoring wells MW-1 located adjacent to the former UST area and' well y�MW-6,In which free phase product was observed TPH-g concentrations m ground water deA{'4' m the samples from well MW-1, and the TPH-diesel concentrations decreased In wells on the site (Figure 4) TPH concentrations In • ground water decreased drastically In the sample collected from well MW-6 over the quarter Advanced GeoEnvironmental,Inc