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Page 3 of 5 <br /> 4.4 Remedial Feasibility Testing <br /> Remedial feasibility testing will include 8 hours of soil vapor extraction(SVE)and 4 hours of air <br /> sparging (AS). <br /> 4.4.1 Soil Vapor Extraction Test <br /> To evaluate the effectiveness of SVE in remediating subsurface soils, a total of eight hours of <br /> SVE testing will he conducted. The testing will include two hours of extraction from each of the <br /> SVE welts In the nested SVE well (SVE-1A/B/C), and one hour of soil gas collection from MW-1 <br /> and SVE-2B. The SVE test results will be used to evaluate the following design criteria: <br /> • Relationship between subsurface airflow,and pressure; <br /> • Effective permeab ility to airflow, <br /> • Radius of influence; <br /> • Existing soil vapor chemistry with respect to petroleum hydrocarbons; <br /> • Evidence of biodegradation; and <br /> • Feasibility of soil vapor extractionibioventing as remedial technology. <br /> The SVE test unit will consist of a SVE blower, capable of producing air-flow at a rate of up to 25 <br /> cubic feet minute(cfm) and a vacuum of up to 15 inches of mercury. Soil vapors cxtracted dufin <br /> the test will be filtered through two, 200-pound vapor-phase granular activated carbon vessels, <br /> prior to discharge to the atmosphere. <br /> Vacuum gauges and air-tight well caps will be placed on the surrounding observation wells (MW <br /> 1, MW-2, the proposed monitoring well west of the former UST#3,and the remaining SVE wells <br /> not being used for extracti on), During the SVE tests, air-flow rate, lower explosive limit(LEL), <br /> vapor concentration by PIE), and vacuum will be measured every 30 minutes from the observatio <br /> wells. Final measurements will be made approximately 30 minutes after SVE test completion <br /> The influent and effluent airstream from the SVE unit will also be monitored using a PID, every 3 <br /> minutes during the SVE tests, To confirm PID measurements, influent suit vapor samples will be <br /> collected during each of the SVE tests and the soil gas collection tests. The soil vapor samples <br /> will be collected in Tedlarf* bags, which will be labeled and transported with chain-of-custody <br /> documentation to a state of California-certified hazardous waste testing laboratory_ The <br /> laboratory will analyze the soil vapor samples for TPH-as-gasoline, BTEX, MTBE, DIPE, ETBE, <br /> TAME, TBA by EPA Method 6020=1 5M and/or 8260B. <br /> 6/1/2011 <br />