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Vapor Extraction Test Equipment <br /> FREY will utilize equipment designed to extract soil vapor at variable flows and vacuums. The <br /> vapor extraction equipment will consist of a trailer mounted vapor extraction unit consisting of a <br /> 10 horsepower, positive displacement blower, a knock out pot, an electricity generator and a <br /> thermal oxidizer mounted on a flatbed truck. A Horiba model MEXA-554JU infra-red gas <br /> analyzer(Horiba) or equivalent, will be used to measure concentrations of UVOCs, oxygen (02), <br /> and carbon dioxide (CO2). Magnehelic pressure gauges will be used to measure vacuums, and in <br /> combination with pitot tubes, will be used to measure flow rates. The unit will include air <br /> dilution valves and required instrumentation. <br /> Vapor Extraction Testing <br /> One, three step VET is proposed to be performed for approximately four hours, followed by an <br /> additional extended VET over a four to eight hour period, using existing vapor extraction well <br /> VW-I. During the VETS, vacuum responses will be monitored at selected observation probes, <br /> while applied vacuums and extraction flow rates will be monitored at the extraction well. Each <br /> step of the first VET will be conducted at successively higher applied vacuums, with a constant <br /> influent flow rate maintained during each step. The additional extended VET will be run with an <br /> applied vacuum and flow rate that provides the maximum hydrocarbon mass removal rate based <br /> on the results of the first VET. <br /> The influent vapor stream from the extraction well will be monitored for concentrations of <br /> UVOCs with the Horiba during each VET. Soil vapor samples (five total including the start, <br /> middle and end of the first VET, and the start and end of the second VET) will be collected and <br /> submitted to a State-certified hazardous waste testing laboratory for chemical analyses. Soil <br /> vapor samples will be analyzed for TPPH and VOCs in accordance with EPA Method No. <br /> 8260B. Observation probes will be fitted with Magnehelic pressure gauges to record vacuum <br /> responses. <br /> At the beginning of the first VET, the unit will be started with all dilution valves open. The <br /> dilution valves will be gradually closed to optimally extract vapors from the test well at a <br /> constant flow rate during each step of the first VET. The extraction flow rate and applied <br /> vacuum at the extraction well will be regularly monitored as will vacuum responses at <br /> observation probes. <br /> Existing soil vapor probes SV-1 and SV-2, and proposed probes SS-1, SS-2, SV-3 and SV-4 will <br /> be used as observation probes during the first VET. (Note that no existing groundwater <br /> monitoring wells can be used as observation wells since all have submerged screens) After <br /> observation probes reach steady state conditions, defined as when no change in vacuum at <br /> observation wells is observed for a period of fifteen minutes, successive steps will be conducted <br /> by increasing the vacuum at the extraction well. Vacuums will be increased by closing the <br /> manual dilution valves. Vacuum responses in observation probes, and extraction flow rates at the <br /> test well will continue to be monitored. <br /> FREY Environmental, Inc. 8 1092-01 <br />