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CAMBRIA collected at the conclusion of the DPE test on the well June 25, 2004 The sample contained 150,000 ppb TPHg and 6,200 ppb benzene MTBE was not detected in the sample at an elevated reporting lint of 200 ppb SVE from well VEW-1 began at 8 45 on June 24 Applied vacuum readings were measured at the wellhead Extraction flow rates were measured after the moisture separator An initial wellhead vacuum of 36 inches WC resulted from a liquid-nng pump-generated vacuum of 68 inches of mercury-gauge (Hg) The maximum wellhead vacuum achieved was 119 7 inches WC The vapor extraction flow rate ranged from 61 1 to 138 7 sctm and averaged 112 1 scfm Cambria personnel observed a maximum vacuum influence of 5 0 inches WC in observation well VEW-2 Extraction well VEW-1 was dry, therefore, groundwater was not extracted The vapor sample collected from VEW-1 at 10 05 contained 730 ppmv TPHg, 2 0 ppmv MTBE, and was below the reporting hmit (¢1 6 ppmv) for benzene The vapor sample collected at the end of the day (13 00) contained 1,400 ppmv TPHg, <3 1 ppmv benzene, and 2 5 ppmv MTBE The Solleco unit was set to operate overnight to maximize the remedial ettort . June 25, 2004 SVE from well VEW-1 continued until 11 00 An average wellhead vacuum of 109 1 inches WC was established by a liquid-ring pump generated vacuum of approximately 204 inches Hg The vapor extraction flow rate ranged from 111 2 to 133 2 sctm and averaged 123 1 sctm. The sample collected at the conclusion of interim remediation (11 00) contained 860 ppmv TPHg, [0 31 ppmv benzene, and 1 1 ppmv MTBE Cambria personnel observed a maximum vacuum influence of 6 3 inches WC in observation well VEW-2 Estimated Radius of Influence Wells VEW-1 and VEW-2 were used to measure vacuum influence or alternatively as extraction points Well MW-5 was also used to measure vacuum influence while extracting from wells VEW-1 and VEW-2 Wells VEW-I and VEW-2 are located approximately 25 feet apart When vacuum was applied to well VEW-1, a maximum vacuum of 6 3 inches WC was observed in well VEW-2 When vacuum was applied to well VEW-2, a maximum vacuum of 1 1 and 0 1 inches WC was observed in wells VEW-1 and MW-5, respectively Wells VEW-1 and VEW-2 are not screened it sirrular depths below grade, VEW-1 is screened from 5 to 20 fbg and VEW-2 is screened from 20 to 45 fbg A preferential pathway between the two wells may be present based on the induced vacuum observations during the DPE test, and may be attributed to the proximity of the wells to the former UST backfill 0854 8