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increases in water levels versus distance (Appendix F), indicates a maximum radius of influence of approximately 46 feet (MW-1) The maximum increase in water level was at observation well MW-13A (0 1 feet), located approximately 16 feet from the AS well Water levels measurements at the end of the AS test (23 5 hours) had equilibrated to within 0 01 to 0 03 of a foot of initial readings, indicating that water levels in the nearby diverting canal may have had some influence on the water level measurements collected during the pilot test The dissolved oxygen measurements showed no consistent trends during the pilot test (Table 5), therefore, the data was not used as a determining factor in predicting the radius of influence Graphs of pressure influence,VOC concentrations, water levels, and dissolved oxygen versus time were also prepared and are presented in Appendix F In each of the monitored parameters, except for dissolved oxygen content, a response was measured in both observation wells MW-13 and MW-13A(Table 5) A comparison of the data indicates that the responses were less pronounced in MW-13A than in MW-13 This is apparently due to both the greater distance from the AS well (MW-13 @ 9ft and MW-13A @ 16 ft) and the location of the screen sections (MW-13 @ 39-59 ft and MW-13A @ 71-76 ft) Based on the measured responses in these wells, both a vertical and horizontal influence was produced across the unsaturated zone • during the pilot test Combined AS/SVE Test A combined soil vapor extraction/air sparging pilot test was performed using VE-1 as the SVE well and IAS-1 as the AS well The pilot test was operated at three different extraction and infection rates Existing monitoring wells MW-1, MW-3A, MW-4, MW-13, and MW-13A and newly installed dual-completion well VE-2 were used as observation wells during the test (Table 6) The monitoring points were selected to provide multi-directional data at varying distances from the infection point Vacuum and flow readings were measured with magnehelic gauges Off-gas concentrations were measured with a PID prior to treatment with the VACLEAN unit One off-gas sample was collected in a Tedlar bag at the end of the combined pilot test for laboratory analysis The combined soil vapor extraction/air sparging pilot test determined that a net vacuum was maintained at approximately 30 feet from the SVE well at a vacuum of 92 in w c and a sparging pressure of 3 psig The results are presented in a graph(Appendix F) showing the pressure versus distance from the SVE well This data documents the capture of the AS off-gases within the design SVE radius of influence • The vapor analytical results showed a TPH(g)concentration of 62,000 pg/L, a benzene concentration of 85 µg/L, and a total BTEX concentration of 8,345 µg/L A copy of the analytical report is III-5