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AGE-NC Project No. 99-0559 <br />Page 13 of 14 <br />SOIL-VAPOR EXTRACTION <br />In the third quarter of 2006, seven SVE wells (VW1, VW-2A/B, VW-3A/B, and VW4A/B) <br />were installed. In October 2006 a Solleco thermal oxidizer SVE unit was installed. A <br />catalytic oxidation cell was installed into the SVE unit late July 2007 to reduce the <br />supplemental energy (natural gas) required to operate the SVE system. <br />The SVE system began operation on 13 December 2006, in accordance with San Joaquin <br />Unified Air Pollution Control District (APCD) permit 4763-2-0; a reinspection was conducted <br />on 28 August 2007. On 05 March 2010, the SVE unit operated without a catalytic oxidizer <br />to reduce the supplemental fuel usage. Over the course of remediation, soil vapor <br />concentrations decreased below two pounds per day and the treatment controls are longer <br />required. <br />SOIL VAPOR EXTRACTION SYSTEM <br />A Solleco 250 TCAT thermal/catalytic oxidizer SVE unit operated within the fenced <br />enclosure surrounding the groundwater remediation system. The influent line was routed <br />through 2-inch diameter schedule 40 PVC piping manifold and then through a moisture <br />knockout vessel to a 10 horsepower, maximum 200 standard cubic feet per minute (scfm) <br />blower. Sampling ports were installed upstream of the vacuum blower inlet, to recover <br />influent soil vapor stream samples, and downstream of the oxidizer chamber, to recover <br />effluent stream samples to monitor the efficiency of hydrocarbon destruction. A Magnehelic <br />vacuum gauge was attached to the inlet of the SVE unit to measure the inlet potential <br />pressure. <br />MONTHLY MONITORING PROCEDURES <br />Soil vapor extraction (SVE) system did not operate this quarter. Previously, the flow rate <br />of extracted soil-vapor (influent) was measured using a flow meter, the flow rate of <br />extracted soil-vapor (influent) was measured using an electrical and manual DPT flow <br />meter, and vacuum potential was measured using a Dwyer magnehelic vacuum gauge. <br />The organic-vapor concentration in the extracted soil-vapor stream was measured before <br />entering the blower (influent stream) and after exiting the SVE unit (effluent stream) using <br />an OVM equipped with a photo-ionization detector (10.0eV lamp, calibrated to isobutylene <br />100 parts per million volume; ppmv), field measurements, recorded at regular intervals, are <br />summarized in historical Table 3. <br />Advanced GeoEnvironmental, Inc.