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The vapor analytical results showed a TPH(g) concentration of 86,000 pg/L, a benzene concentration of 2,800 µg/L, and a total BTEX concentration of 11,160 µg/L Based on the analytical results, approximately 15 4 pounds of hydrocarbon vapors per hour (lbs/hr) were extracted from VE-1 A copy of the analytical report is included in Appendix G Aar Sparging Test The air sparging test was performed on injection/sparging well IAS-1, located near the source area of the former UST excavation Existing monitoring wells MW-1, MW-4, MW-13, and MW-13A and newly installed dual completion well VE-2 were used as observation wells during the test The monitoring points were selected to provide multi-directional data at varying distances from the injection point The pilot test involved injecting air into the saturated zone through the infection well using an Emglo Model M800HC4V compressor with a maximum flow rate of 4 9 cfm The pilot test was operated at a gauge pressure of 4 pounds per square inch(psig) Observation wells MW-1, MW-4, MW-13, and MW-13A were monitored for pressure influence, VOC concentrations, dissolved oxygen content, and depth to water (Table 5) Dual-completion well VE-2, a vadose zone well, was monitored for pressure responses and VOC concentrations only (Table 5) Pressure readings were • measured with a magnehelic gauge, VOC concentrations were measured with a photoionization detector (PID), dissolved oxygen concentrations were measured with a YSI Model 55 meter, and water levels were measured with a Solinst gauging probe The air sparging test was evaluated through each of the monitored parameters indicated above Pressure responses were measured in three observation wells (MW-13, MW-13A, and VE-2) Observation well VE-2 was installed as a dual-completion vapor extraction well monitoring point with a screen section that does not extend into the saturated zone The pressure response data from, this well was not used in determining the radius of influence of the sparging test A graph presenting the natural log of the pressure versus distance from injection well IAS-1 (Appendix F) shows a maximum radius of mfluence of approximately 10 feet(MW-13) A pressure response of 0 1 in w c was selected to define a significant response The pressure response measured in observation well MW-13A (0 02 in w c ), located approximately 16 feet from IAS-1, was Iess than 0 1 in w c Increases in VOC concentrations were measured in three observation wells (MW-13, MW-13A, and VE-2) A graph showing VOC concentrations versus distance (Appendix F) indicates a maximum radius of influence of approximately 10 feet (MW-13) • Maximum changes in water levels were measured in four observation wells (MW-1, MW-2, MW-13, and MW-13A) after 7 to 8 hours into the sparging test (Table 5) Using this data, a graph showing III-4