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' I -11-ml #709 i0 E Il l n 01 IIII(IIl'll ].c UM11,1l 1 L ISII)IIM l c til Rcpm I }(hi a 1n 2 i 200, 423 Vapor Extraction Test Results ' The induced vacuum and flow rate achieved from each test well was similar VE testing of VEW-1 during the fourth and final step yielded a maximum flow rate of approximately 175 cfm at a corresponding vacuum of approximately 75 inches of water column Similarly, VE testing of VEW-2 during the fourth and final step yielded a maximum flow rate of approximately 170 cfm at a ' corresponding vacuum of approximately 77 inches of water column This equates to a vapor flow rate of approximately 8 75 cfm per linear foot of well screen in VEW-1 and approximately 8 5 cfm per linear ' foot of well screen to VEW-2 These values represent the maximum well performance achievable utilizing the test system's PD blower set up The well performance curves (induced vacuum versus flow rate) for extraction test wells VEW-1 and VEW-2 are presented in Figure 5 ' Each monitoring point well demonstrated an effective vacuum response at their respective lateral point distances from the nested extraction wells Generally, a vacuum response of greater than 0 1 inches of ' water in a lateral monitoring point well is considered effective At the fourth and final step of each VE test, each monitoring point well demonstrated a vacuum response of greater than 0 10 inches of water ' column (Tables 6 and 7) Monitoring point well MW-IA (screened from 30 to 50 feet bgs), located the furthest from the nested extraction wells (approximately 57 feet away), demonstrated a vacuum response ' of 100 inches and 0 80 inches for testing of VIEW-1 and VEW-2, respectively Similarly, MW-lB (screened from 52 to 77 feet bgs and nested with MW-1A) demonstrated a vacuum response of approximately 3 10 inches and 150 inches for testing of VEW-1 and VEW-2, respectively Based on monitoring point well response during the fourth step of each test, an estimated effective VE ROI of greater than 60 feet exists at the site (Figure 6) The induced vacuum versus lateral distance from VEW- ' 1 and VIEW-2 is graphically presented to Figures 7 and 8,respectively ' 424 Mass Extraction Estimates Laboratory analysis of the vapor samples collected during the VEW-1 (lower soil horizon) test indicated ' volatile fuel hydrocarbons (VFH) were extracted at concentrations of approximately 28,000 ppmv Additionally, BTEX concentrations were present at concentrations of 1,200 ppmv benzene, 1,900 ppmv ' toluene, 200 ppmv ethylbenzene, and 710 ppmv total xylenes, respectively Analytical results of soil ' 13 1