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02 June 2015 AGE Project No. 14-3154 Page 5 of 6 obtained from surrounding shallow wells RW-1, RW-4, and MW-2 with two additional wells installed with the core of the statured diesel in soil (Figure 3A). DPE wells are proposed to be constructed as 4-inch diameter wells screened from approximately 8 feet to 18 feet bsg. The DPE events will be performed at a constant-flow rate and the maximum vacuum allowable from the DPE system. A 1-inch diameter aspirated stinger will be placed into the proposed DPE wells in the saturated zone to depths of approximately 12 feet bsg. Additionally, %-inch diameter flexible tubing will be installed in each DPE well as an observation point to monitor the groundwater levels during DPE with a Solinst water level meter. Appropriate well seals will be installed at the top of the DPE well casings to ensure a closed system and maximum allowable vacuum. The well connections will be completed using either above-ground hoses or PVC piping. The stinger will allow the extraction of impacted groundwater and, after some period of system operation, will decrease the groundwater level in the extraction wells allowing for remediation of petroleum hydrocarbons in the capillary fringe and upper portion of the saturated zone. As the vacuum is applied to the extraction tubes to the wells, a high velocity vapor stream is generated in the extraction stinger. The vapor stream entrains the impacted groundwater and lifts the hydrocarbon vapor/water to a treatment system. As the hydrocarbon-laden water travels up the extraction stinger, the majority of the contaminants in the groundwater are stripped into vapor phase by the high velocity vapor stream. Stripping efficiencies of >90% are possible; however, stripping efficiency is dependent upon site-specific variables, including vacuum, air/water ratios, contaminant concentrations and contaminant physical properties (volatile vs semi- volatile). Extracted vapors are diesel which is a semi-volatile, will be routed to an intermediate "knock out' to trap excessive moisture contained with the vapors. Assuming the extraction system is successful in drawing the extraction wells down to depths of 18 feet bsg, there will be an exposed screen interval of 8-18 feet in each well. Fluids from the knock-out will be routed to the holding tank. From the holding tank, the wastewater will be pumped as required, treated with granular activated carbon and disposed on-site, and other petroleum product waste recycled under waste manifests. DPE FIELD MEASUREMENTS During the DPE the vapor flow will be monitored after the knock out using a Dwyer DS- 200 flow sensor. The flow rate will be determined from the measured differential pressure and the piping diameter using a nomograph. Flow rates will be measured and documented in standard cubic feet per minute (scfm), inches of water of differential pressure. Induced vacuum measurements will be recorded from surrounding wells utilizing Magnehelic gauges. The induced vacuum will be monitored for stabilization in units of inches of water and Hg during the events. Hydrocarbon concentrations in the well effluent stream will be measured at regular intervals. A PID will be utilized for field Advanced GeoEnvironmental,Inc.