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CAM A <br /> the location of every soil boring and monitoring well drilled at this site, and the location of two <br /> cross sections (discussed below) <br /> The estimated extent of TPHg and benzene in soil beneath the site is shown on Figure 3 These <br /> estimates were generated using soil data collected during previous investigations TPHg <br /> concentrations in soil greater than 100 parts per million (ppm) and all benzene detections in soil <br /> were used to create this trap All of the soil analytical data collected from borings and wells at <br /> this site is shown on Table 3 Excerpts of Table 3 (used to create this map) are shown on the <br /> neap Most of the analytical data used to create this map is four to five years old and does not <br /> represent current conditions Therefore, the estimated extent of TPHg and benzene in soil <br /> depicted on Figure 3 should be considered a conservative overestimate at this point in time, as <br /> there has likely been some natural degradation that has occurred since this data was collected <br /> The estimated extent of TPHg in groundwater is presented as Figure 4 and the estimated extent <br /> of benzene in groundwater is presented as Figure 5 These maps were created using May 14, <br /> 2003 groundwater monitoring data from the existing monitoring wells (S-1, S-2, S-3, and S-4) <br /> Each map contains two sets of concentration contour lines One is for the shallow groundwater <br /> zone and the other is for the deep groundwater zone <br /> The grab groundwater sample data for every boring at this site is presented in Table 4 Historical <br /> groundwater sampling analytical data for the monitoring wells at this site is summarized on <br /> Blaine Tech Services' table, included in Appendix A No map was created to show the estimated <br /> extent of methyl tertiary butyl ether (MTBE) because there have only been a few low level <br /> detections of MTBE at this site No map was created to show the estimated extent of <br /> dichloroethane (1,2-DCA) as the sporadic distribution of this compound does not lend itself to <br /> creating concentration contours We will attempt to contour the 1,2 DCA data once we have <br /> collected more data and have conducted further investigation to assess the extent of it Fuel <br /> oxygenate and lead scavenger groundwater sampling analytical results are summarize on Table 5 <br /> Groundwater flow direction and gradient information is shown on each site map (Figures 2, 3, 4, <br /> and 5) The flow direction information is presented in the form of a rose diagram, which shows <br /> flow direction data from every quarterly monitoring event at this site The rose diagram suggests <br /> the predominant flow direction of shallow groundwater beneath the site is toward the south- <br /> southeast The range of the groundwater gradient is presented on these traps and the average <br /> gradient is calculated from this range Flow direction and gradient data for the deep groundwater <br /> zone was not included as only two groundwater monitoring events have occurred in the deep <br /> zone Two events is not enough information to establish trends for flow direction and gradient <br /> 0797 2 <br />