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INTERNATIONAL TECHNOLOGY CORPORATION <br /> 3.0 Results <br /> 3.9 Test Data <br /> Table I contains the soil gas flow rate and well vacuum data obtained from the test. Table 2 <br /> contains the hydrocarbon concentration data obtained from the PID and from the laboratory <br /> tanalyses. Laboratory reports are contained in Appendix B. <br /> Figure 2 depicts the assumed area of impacted soils and the observed zone of influence <br /> calculated based on the SVE test. Figure 3 shows the measured stabilized vacuum data as a <br /> function of radial distance from the center of the backfill area. The radius of influence for <br /> each flow rate is determined from a best-fit line through the test data. <br /> Figure 4 is a plot of the measured extraction well head vacuum versus the measured soil gas <br /> flow rate. Figure 5 represents the relationship between radius of influence and soil gas flow <br /> rate. <br /> 3.2 interpretation of Data <br /> Test results were examined to p--ovide an esthna?e of the zone of influence of the horizontal <br /> pipe and an idea of the concentration of hydrocarbons that can be extracted. The effective <br /> radius of influence was estimated based on the nest-fit line through a plot of vacuum vs. <br /> distance data. While the radius of influence is defined as the radius at which no vacuum is <br /> finduced, a practical design approach is to use the radius at which the vacuum induced is 0.05 <br /> inches of water as the effective radius of influence. This conservative assumption is <br />' necessary due to the inherent error in field measurements of very small vacuums and the need <br /> for movement of soil gases at the periphery. Figure 3 is the plot of the vacuum vs. distance <br /> data. Error bars of+/- 0.01 inches of water were used for the best-fit since the precision of <br /> the field vacuum measurements are limited to this amount. The error bars for data points <br /> above 0.05 inches of water are relatively small because the vertical axis is a log scale and are <br /> therefore not shown. <br /> While the standard data analysis does not apply strictly, due to the fact that the configuration <br /> of the "well" is not typical, the data indicate that significant contaminant removal is feasible <br /> at the flow rates observed during the pilot test - the influence of the system was observed in <br /> all wells found within the known contaminated zone, so extrapolations to higher flow rates <br /> are not necessary. <br /> MZ/03_1a9WSTM7M M 5 <br />