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02 September 2010 AGE-NC Project No. 95-0184 Page 6 of 7 3.2. EXTRACTION SYSTEM DESIGN A catalytic oxidizer SVE system was installed at the site for hydrocarbon vapor recovery. Hydrocarbon vapors are extracted from the configuration of extraction wells, routed through a 100-gallon steel condensation entrapment chamber, and then routed to the inlet of a vacuum blower; the outlet from the vacuum blower will be routed through the catalytic oxidizer. The SVE system is connected through a manifold to the vapor recovery wells and should be able to operate near 200 standard cubic feet per minute (scfm) and five inches of mercury. The SVE system has been equipped with a catalytic module to provide an effective destruction ratio at reduced concentrations of hydrocarbon vapor. Induced vacuum measurements will be collected utilizing a Magnehelic vacuum gauge attached near the inlet of the blower; SVE air flow will be monitored using a Dwyer DS-200 flow sensor. Following the start-up period, the SVE air flow along the influent and effluent lines will be monitored weekly for the presence of organic vapor using an organic vapor analyzer (OVA) equipped with a PID. Sampling ports will be installed upstream of the vacuum blower inlet to recover SVE influent air flow vapor stream samples, and downstream of the catalytic converter to recover effluent SVE air flow samples to monitor the efficiency of hydrocarbon destruction. 3.3. IN-WELL AIR SPARGING - IN-WELL DESIGN Ground water extraction wells EW-1 and EW-2 will be completed with a vacuum-tight cover and seal. An SVE influent pipe extending from the blower on the SVE system will be connected to the vacuum-tight cover. The blower will create a vacuum which produces negative pressure in the well casing. The soil vapor which is aspirated from ground water within the well casing is extracted and treated by SVE. Under vacuum, the ground water table in the well casing and the surrounding ground water is lifted into the pick up tube(s) at the lower portion of the wells. A treatment cell with a minimal dimension of five feet istt o length is constructed of stainless metal and/or PVC, employees an upper sieve with holes of a regular size and distribution. The upper sieve is installed inside the whole extraction chamber (well casing) with a minimal distance above the ground water level. An ambient air pipe extends from the surface to the inside of the chamber and connects to the treatment cell. Ambient air is supplied from outside through the air pipe and is recovered through the sieve opening of the upper sieve plate. The upper sieve plate openings are spaced at a predetermined design to form individual air bubbles, causing air to project through ground water. In a treatment cell this air entrains the volatile hydrocarbons dissolved in the ground water and discharges the treated ground water. Advanced GeoEnvironmental,Inc.