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SOH, VAPOR EXTRACTION TEST A short term soil vapor extraction pilot test was conducted on October 26, 1993 to determine the effectiveness of soil vapor extraction as a remediation technology Relevant information obtained during the testing included tsoil vacuum pressures and response characteristics vapor analytical data flow rates • estimated radius of influence from the extraction point ' Test Configuration The soil vapor extraction test system consisted of one extraction point (vadose well VW-1), a ' Sutorbilt positive displacement blower with a flow capacity of 120 cfm at over 150 inches of water, flexible PVC suction hose, a water knockout drum and two 200-Ib Granular Activated Carbon (GAC) canisters for emissions control The existing two-inch diameter monitor wells ' on site (MW-1, MW-2, MW-4 and MW-5) were used as vacuum monitoring points (The screened interval of MW-3 was below the current groundwater elevation and could not be used a monitoring point for the pilot test) The four vacuum monitoring points were equipped with ' Magnehelic gages to constantly measure vacuum pressure Sampling ports were located before, in between, and after the carbon canisters to verify that no TPH emissions were released to the atmosphere Test Procedures ' The soil vapor extraction test was performed on October 26, 1993 for a duration of 339 minutes. Several different extraction scenarios were run to assess the variabilities of air flow: • Vapor extraction well VW-1 was tested from start up for a duration of 36 minutes with an average blower flow rate of 30 cubic feet per minute (cfm), and an average extraction vacuum pressure in excess of 5.5 pounds per square inch (150 inches of water column) ' At this vacuum, groundwater was eventually pulled up into the VE well and flooded the screen interval • After water flooded VW-1, vacuum was reduced to 3 2 psi (94 in wc) with a corresponding average blower flow rate of 21 cfm The test continued for an additional 183 minutes in this configuration without any indication of flooding in the VE well. ' Soil vacuum readings were collected at each of the monitoring points These values are noted g g on the field data sheets included in this appendix PID readings were taken on Tedlar bag ' samples collected from a sample port located on the positive pressure side of the blower. PID values are also recorded on the field data sheets ' 1 t ioica3 1 1