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06 December 1995 <br /> F AGE-NC Project No. 95-0100 <br /> Page 4 of 13 <br /> microbial population, exceeding the 10% minimum generally required. The laboratory report and <br /> chain-of-custody are 'included in Appendix C. <br /> 4.0. SOIL VAPOR EXTRACTION PILOT TEST <br /> 4.1. SOIL VAPOR EXTRACTION SYSTEM <br /> On 18 October 1995, an 8-hour soil vapor extraction (SVE) pilot test was conducted. This pilot test <br /> was performed to provide vapor extraction data to assess the feasibility of the SVE method Oil this <br /> site prior to planning and initiation of a full scale remediation system. <br /> The test was conducted using a VACLEEN 1000 vapor extraction system ,VES) manufactured by <br /> Environmental Techniques. The VES consists of a positive-displacement blower, driven by an internal <br /> combustion (IC) engine. The inlet of the VES was connected to an extraction port on the extraction <br /> well. The vacuum applied to the extraction well causes hydrocarbons in the ,oil to volatilize and flow <br /> through the vacuum pump to the IC engine. The induced vacuum pressure was monitored at one or <br /> more points using Magnehelic vacuum gauges. <br /> — The hydrocarbon vapors are destructed as part of the normal internal combustion process of the IC <br /> engine. Emissions from the engine are routed through two catalytic converters to maximize the <br /> destruction rate of the extracted hydrocarbon vapors. <br /> 4.2. PILOT TEST PROCEDURES <br /> The test was initiated at 7:30 am on 18 October 1995 and lasted for approximately 8 hours. An air- <br /> tight IC inlet, pre-connected with a magnehelic vacuum gauge, was attached to the upper and lower <br /> sections of VE 1. Beginning at 7:30 am, an induced vacuum potential was applied to VE 1. Air-tight <br /> well caps, pre-connected with magnehelic vacuum gauges, were attached to both casings at well VE2. <br /> The purpose of the monitoring was to collect data to estimate the radius of influence exerted by vapor <br /> extraction from VIE]. <br /> A sample port was tapped into the PVC at the inlet and a portable photo-ionization detector <br /> (Microtip model 1000 calibrated to isobutylene) was used to measure organic vapor concentrations <br /> at half-hour intervals. The port was also used to collect vapor samples in tedlar bags. Measurements <br /> were recorded at regular intervals throughout the test and are included in Table 2. Field sheets are <br /> included in Appendix D. <br />