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i 10 May 2004 AGE-NC Project No 96-0229 IPage 7 of 8 I4.0. SUMMARY AND CONCLUSIONS The results of the July and October 2003 multi-level well installation are as follows • AGE installed, developed and surveyed seven multi-level ground water monitoring wells (MW-13 through MW-19),generally,screen intervals were installed at depths between 35 to 40 feet (First Water Zone), 62 to 67 feet bsg (First Confining Unit), 79 to 84 feet bsg ' (Second Water Zone), 95 to 100 feet bsg (Second Confining Unit), and 120 to 125 feet bsg (Third Water Zone) ' Generally, saturated soil at the site was first encountered at between 35 and 40 feet bsg The static water level was generally measured at approximately 34 feet below the tops of the monitoring well casings • Cross sectional views B-B'and F-F'were generated from current and previous investigation and depict general lithology beneath the site(Figures 3 and 4,respectively) Less permeable, very stiff to hard, fine-grained, sandy, clayey SILT/silty CLAY was generally observed between surface grade and 10 feet bsg, 50 to 65 feet, 80 to 100 feet and 100 to 110 feet bsg, a permeable,medium dense to dense,poorly graded, fine to medium SAND/silty SAND was I generally observed at depths between 15 to 45 feet bsg, 70 to 95 feet bsg and 115 to 125 feet bsg The modeled site stratigraphy is shown in Figures 3 and 4 • Soil samples collected from MW-13 detected low concentrations of TPH-g and BTEX ' between 75 feet and 105 feet bsg, low concentrations of TPH-g, BTEX and MTBE were detected from MW-17 at a depth of 45 feet bsg (Table 2, Figures 19 and 20) ' Based on current and previous soil data, the distribution of contaminants at the site, in conjunction with the site stratigraphy as described above, suggests a narrow, vertical plume of impacted soil descending from the easter edge of the former UST area and the eastern ' edge of the fuel dispenser island area to depths of approximately 60 feet bsg(MW-13) The contaminated soil plume spread laterally upon encountering the ground water table at approximately 35 feet bsg The lateral extent of the plume extends approximately 190 feet ' toward the northeast, 80 feet toward the southwest and 130 feet toward the east This model is shown in Figures 19 and 20 5.0. RECOMMENDATIONS With the addition of multi-level wells MW-13 through MW-19, AGE recommends continued quarterly ground water monitoring at the site ' Advanced CeoEnwronmental,Inc 1