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1 20 June 2006 <br /> AGE-NC Project No. 01-0839 <br /> 1 Page 7 of 8 <br /> 1 be continued until field parameters(pH,electrical conductivity,and temperature)have stabilized and <br /> purged water is visually sediment-free. <br /> 1 3.5. SVE PILOT TESTING <br /> 1 Two separate 8-hour SVE pilot tests will be conducted on two different vapor well screens at the <br /> site. The tests will be conducted using a vapor extraction system, the VACLEEN 1000G, <br /> manufactured by Environmental Techniques. This vapor extraction system consists of a positive- <br /> displacement blower driven by an internal combustion(IC)engine. During one test,the inlet of the <br /> system will be connected to the newly-installed deep SVE wells adjacent to MW-4; a separate test <br /> will be conducted where the SVE system will be connected to the newly-installed shallow SVE wells <br /> 1 adjacent to MW-2. Air-tight well caps fitted with attached Magnehelic vacuum gauges will be <br /> attached to the remaining SVE wells and monitoring wells MW-2, MW-3, and MW-4 and the <br /> induced vacuum will be measured at these monitoring points.The air stream from the SVE well will <br /> 1 be monitored for the presence of organic vapor using an organic vapor analyzer (OVA) equipped <br /> with a PID. The vacuum applied to the extraction wells will cause hydrocarbons in the soil to <br /> volatilize and flow through the vacuum pump to the IC engine.The extracted hydrocarbon vapor will <br /> 1 be destroyed in the IC engine as part of its internal combustion process. Emissions from the engine <br /> will be routed through two catalytic converters to maximize the destruction of hydrocarbon vapor. <br /> 1 3.5.1. Field Measurements <br /> 1 During the vapor extraction pilot tests, air flow will be monitored using a Dwyer DS-200 flow <br /> sensor.Flow rates will be measured and documented in inches of water of differential pressure. The <br /> 1 flow rate, documented as standard cubic feet per minute (sefm), will be determined from the <br /> measured differential pressure and the piping diameter using a nomograph. Induced vacuum <br /> measurements will be recorded from the surrounding SVE and monitoring wells utilizing <br /> 1 Magnehelic gauges.The induced vacuum will be monitored for a stabilized value in inches of water <br /> during the pilot test. Hydrocarbon concentrations in the well effluent stream will be measured at <br /> regular intervals. A PID will be utilized for field measurements. The radius of influence and <br /> 1 hydrocarbon mass removal rate will be established from the data collected. <br /> 1 3.5.2. Collection and Analysis of Vapor Samples <br /> Vapor samples will be collected at 2-hour intervals during the pilot tests from the inlets of the <br /> 1 extraction wells to measure concentrations of extracted hydrocarbon vapor. The samples will be <br /> collected in Tedlar bags using the organic vapor analyzer as an air pump. Following sample <br /> 1 collection,the samples will be placed in a covered container and transported under chain of custody <br /> Advanced GcoEavironmental,Inc. <br /> 1 <br />