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r.rr 30 March 2012 AGE-NC Project No. 97-0312 Page 7of8 The operation will included a constant-flow rate, at the maximum vacuum allowable from the SVE system. Results from these initial operation will be used to establish the effective radius of influence and to determine the optimum operating level of the extraction system. 3.4 HVSVE OPERATION During the primary start up, the HVSVE system will be utilized on the shallow SVE wells adjacent to MW-5 and northern UST area; subsequent extraction will be conducted where the SVE system will be connected to the three deeper SVE wells and well VP-1 to evaluate the contaminant concentrations and SVE influence on the deeper sediments. Monitoring well MW-5 will be connected into the SVE network to evaluate the deepest petroleum hydrocarbon impact to soil. Air-tight well caps fitted with attached Magnehelic vacuum gauges will be attached to the remaining SVE wells and monitoring wells and the induced vacuum will be measured at these monitoring points. The air stream from the SVE well will be monitored for the presence of organic vapor using an OVM equipped with a PID. The vacuum applied to the extraction wells will cause hydrocarbons in the soil to volatilize and flow through the vacuum pump to the SVE unit. The extracted hydrocarbon vapor will be destroyed in a catalytic cell as part of a combustion process. 3.4.1. Field Measurements During soil vapor extraction, air flow will be monitored using a Dwyer DS-200 flow sensor. Flow rates will be measured and documented in inches of water of differential pressure. The flow rate, documented as standard cubic feet per minute (scfm), will be determined from the measured differential pressure and the piping diameter using a nomograph. Induced vacuum measurements will be recorded from the surrounding SVE and monitoring wells utilizing Magnehelic gauges. The induced vacuum will be monitored for a stabilized value in inches of water during the start-up period. Hydrocarbon concentrations in the well effluent stream will be measured at regular intervals. A PID will be utilized for field measurements. The radius of influence and hydrocarbon mass removal rate will be established from the data collected. 3.4.2. Collection and Analysis of Vapor Samples Soil vapor samples will be collected on the first day of operation at 2-hour intervals from the inlets of the extraction wells to measure concentrations of extracted hydrocarbon vapor. Advanced ceoEnvironmental,Inc.