Laserfiche WebLink
24 October 2005 <br /> AGE-NC Project No. 98-0500 <br /> Page 2 of 11 <br /> former dispenser areas, MW-34 and MW-36, are screened in the sixth hydrogeologic unit <br /> (HU6). <br /> • Deep-screened well MW-37 (195 to 200 feet bsg) is screened in the seventh hydrogeologic <br /> unit (HU7); and <br /> • Deep-screened well MW-35 (225 to 245 feet bsg) is screened across the seventh and eighth <br /> hydrogeologic units (HU7 and HU8). <br /> A brief amount of background information and a basic site conceptual model is included in <br /> Appendix A. Field work was performed in accordance with guidelines established by the <br /> CVRWQCB for subsurface investigation of contaminated sites.The well numbers ofthe monitoring <br /> wells were reassigned during the final quarter of 2003 in a sequential order; the renumbered wells <br /> are presented in Table 3 and on Figure 2. <br /> 2.0. SOIL-VAPOR EXTRACTION OPERATION AND MONITORING RESULTS <br /> A catalytic oxidizer soil-vapor extraction(SVE)unit is connected to a total of twenty-six extractions <br /> wells on the eastern and western portions of the site. A total of nineteen individual SVE wells <br /> (VW-6A to VW-15B)and monitoring well MW-1 are located on the eastern side of the site and are <br /> connected above ground to the SVE unit using 2-inch diameter schedule 40 poly-vinyl-chloride <br /> (PVC)piping and 2-inch ball valves to control flow from individual wells. Additionally, a total of <br /> four SVE wells (VW-IA to VW-2B) and two monitoring wells (MW-15 and MW-16) are located <br /> on the western edge of the site and are connected below grade near the wells and then above grade <br /> through the building to the SVE unit using 2-inch diameter schedule 40 PVC piping. <br /> The piping(influent line)was routed through 3-inch diameter schedule 40 PVC piping manifold and <br /> then through a moisture knockout vessel to a 20-horsepower,maximum 500 standard cubic feet per <br /> minute(scfm)blower.Sampling ports were installed upstream of the vacuum blower inlet to recover <br /> influent soil-gas vapor stream samples,and downstream of the catalytic converter to recover effluent <br /> stream samples to monitor the efficiency of hydrocarbon destruction.A Magnehelic vacuum gauge <br /> was attached to the inlet of the SVE unit to measure the inlet potential pressure.Field measurements, <br /> recorded at regular intervals, are summarized in Table 1. <br /> SVE-system operations are in accordance with San Joaquin Unified Air Pollution Control District <br /> (APCD)permit-5861-1-0. <br /> • <br /> Advanced GeoEnvironmental,Inc. <br />