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'.In K.,le Christie uiv {i90 'acre y i Durine the piiot test. bad* sampies were coiiected at vapor ;:its 1. ', 1, 7 and 8 and for the ;;ombined vapor from vapor weils 3. 5,and 6. A total of six gas samples were collected over a time vain' of 8 hours and monitoring of the soii vapor was performed using a flame ionization dctemor. The vapor wells were allowed to purge for at least 30 minutes before bag sampies were taken. Table 4 presents the hydrocarbon analysts from these samples. Laboratory reports are enclosed. Table 4. Hydrocarbon Concentration in Extracted Well Vapor j Total I Total petroleum '.Tell Benzene. Toluene. xvienes. ithvlbenzene, hvdrocarbons. number pprn_v'1 I Ppm.,,. P'Pr v I ppm v pp v 1 58 50 60 14 8,400 2 78 81 100 20 15,000 4 490 740 540 100 21.000 7 380 310 200 28 71,000 S 230 220 170 32 21,000 ;• 5, and 33.000 6 870 1.300 760 110 a,pm v = parts per million of vapor volume. As shown in Tables 1 and 2, soil vapor can be extracted at high volumetric flow rates at relatively law vacuum. Vapor wells 1 and 2 are connected with a.cnmmon manifold as are - vapor wells 3, 5, and 6. and vapor wells 4, 7, and 8 (see Figure 1). gates 2, 3, and 4 indicates volumetric flow rates versus vacuum for vapor wells 112, 41718, and 31516, respectively. Figures 2,3, and 4 indicate the expected volumetric flow from the manifoldetl vapor wells at an applied vacuum. It is important to note that a very high vacuum was required to extract soil vapor from well No. 7. Thus. as shown on Figure 4,only vapor well t and vapor well will contribute to the extracted vapor from the common manifold of wells 4, 7, and 8. ,r According to the vapor well construction logs, the site is underlain by interbedded layers of jsilty ciao,clayey silt sand.and gravelly sand. The vapor wells are sealed with bentonite froth 4 to_8_feet in depth. and the wells are screened from 10 feet to 55 feet At this interval, the BrGm and Caldwell Ccnsunants