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J Site Background Information : Quick N Save #1 Page 8 of 9 was processed through the DPE unit at a cumulative rate of approximately 1 .5 gpm . Approximately 6 ,200 gallons of ground water was extracted during the DPE pilot test. Utilizing the Distance-Drawdown Method (Jacob straight-line method ) based on a theoretical well between the two ground water pumping wells, an estimated transmissivity value was calculated at approximately 437 . 5 feetz/day (equivalent to 3 ,265 gallons per day/feet) and maximum storativity value calculated at 0 .01 . Based on a transm issivity value of 437 feet2/day and an aquifer thickness of 20 feet (draw-down of water table within screen ) , a hydraulic conductivity value was calculated at 21 .8 feet/day (0 . 008 cm/s). Utilizing a semi-logarithmic plot of ground water draw-down vs , observation well distance from the theoretical pumping well location (Jacob straight-line method ) , a best-fit line was utilized to project a theoretical radius (Rn)of influence of approximately 106 feet at 1 . 5 gpm . Approximately 1 pound, equivalent to a volume of approximately 0 . 16 gallons of gasoline - was removed through ground water extraction . i The soil-vapor stream was extracted from EW-1 and MW-2 at a consistent flow rate of 50 SCFM . Soil-vapor concentrations from EW- 1 and MW-2 were measured between 288 ppmv and 565 ppmv. Based upon an effective vacuum potential of 0 . 1 inches of water, the calculated theoretical ROI of SVE at the site will be approximately 29 feet from an � j extraction point. The combined mass of SVE hydrocarbons extracted by the DPE system during the pilot test was calculated to be approximately 88.7 pounds, or equivalent to a volume of approximately 14.2 gallons of gasoline . Based on the results of the DPE pilot test, AGE concluded a dual-phase extraction system , utilizing high vacuum and lower ground water flow rates , would be well suited to quickly de- water the well filter pack and depressed vadose zone to remove vapors near an extraction well . J REMEDIAL PIPING INSTALLATION Between 16 and 19 August 2010 , trenching (shallow), backfilling , compaction , and asphalt repairs of the remedial piping network, were performed by G&N Construction of Stockton , j California and Valued Engineering of Stockton , California. DPE remedial system piping was installed underground in a 12-inch wide by a 36-inch deep trench . A manifold of three-inch diameter, schedule 80 PVC piping was installed from remediation well heads VW- 1 through VW-4 , EW- 1 through EW-3 and MW-3 ; from the well heads , the three-inch PVC piping led to a common three-inch diameter, schedule 80 PVC piping-network utilized by all of the remedial wells . Remedial piping extending to wells EW-1 through EW-3 , and MW-3 was capped with threaded PVC fittings prior to the L . Advanced G"Environmental, Inc. J