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BIa@S Envrronmenial Managenrend Inc 002-70950-03 U-HauE#709 50 Work Plan 11/8101 measurements in July or September 2001 Groundwater level measurements collected since January 2000 are presented in Table 3 The data from the middle "B" and lower "C" well casings were used to create a groundwater condition maps showing the groundwater flow direction across the site On September 12, 2001, the average groundwater flow direction using data from the middle"B"well casings was toward southwest (Figure 5) The groundwater flow direction of water in the lower "C" well casings was toward the north from monitor well MW-7 and toward the west and southwest from the central portion of the site (Figure 6) Laboratory analytical results of the September 2001 groundwater sampling event, which included two sample groups (the middle "B" casing and lower "C" casing samples), revealed substantial variation between sample groups A summary of analytical results for the September 2001 sampling event is presented in Table 4 Analytical results of groundwater samples collected from the well casings screened across the groundwater interface (middle "B" casings) revealed the highest concentrations of hydrocarbons in groundwater from wells MW-3B, MW-2B, MW-4B, and MW-613 The concentrations of hydrocarbons in groundwater from MW-313 (170,000 micrograms per liter[µg/L] TPHg and 40,000 gglL benzene) and MW-213 (59,000 gg/L TPHg and 18,000 gg/L benzene) suggest that the source area of hydrocarbons was near MW-3B and MW-213 The elevated concentrations of hydrocarbons in water from MW-413 and MW-613 suggest that the hydrocarbon plume has spread across the site between the eastern and western property boundaries The non-detect levels of benzene in groundwater from monitor wells MW-513 and MW-8A suggests that the boundary of the hydrocarbon plume has not spread to the northern portion of the site The analytical results of the sample from well MW-9B indicated a non-detect level of benzene and the detection of 140 gg/L TPHg This result suggests that the southern extent of the hydrocarbon plume is near well MW-9B The approximate extent of hydrocarbons in groundwater associated with the middle`B"casings is shown on Figures 7 and 8 Analytical results of groundwater samples collected from the lower "C" casing wells, screened between approximately 60 and 100 feet bgs, revealed the highest concentrations of hydrocarbons in groundwater from wells MW-6 and MW-4 The detection of hydrocarbons in groundwater from wells MW-6 and MW-4, and the absence of hydrocarbon in groundwater from well MW-3, indicated a shift in the 7