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1 <br /> ' 12 August 2002 <br /> AGE-NC Project No 95-0103 <br /> Page 3 of 11 <br /> ' 2 2 1 Installation of Underground Ground Water Extraction Pipe-Line <br /> Between 11 and 13 January 2002,an approximately 18 inches wide, 8 inches thick and 250 feet long <br /> ' trench was cut out of the asphalt surface, the asphalt waste was transported to F T G Construction <br /> Materials Inc , a concrete recycling facility located in Stockton CA Afterwards, a mini-excavator <br /> equipped with an 18-inch bucket was utilized to excavate soil in the above referenced trench-line <br /> to approximately 24-inches deep, excavation cuttings were temporarily stockpiled adjacent to the <br /> trenches on site A map depicting the on-site trench system is depicted in Figure 2 <br /> ' A 1-inch diameter,schedule 40 PVC piping(process piping)and 3/4-inch diameter,schedule 80 PVC <br /> electrical piping(electrical conduit)were installed in the on-site trench at approximately 18-inches <br /> bsg A manifold PVC piping system was utilized in the trench to connect the process piping system <br /> ' from each extraction well head to the ground water treatment system From the ground water <br /> extraction pump, electrical wiring was routed through individual 1/4-inch diameter PVC conduit <br /> ' through the trench to the electrical control panel of the treatment system Following placement of <br /> all PVC piping, the trench was backfilled with the excavated soil to 4-inches bsg The remaining <br /> space was resurfaced with asphalt <br /> 1 • <br /> 2 2 2 Installation of Ground Water Extraction Pumps <br /> On 25 March 2002, 4-inch diameter, stainless steel model 5 S 10 Grundfos Rediflow down-well <br /> pumps equipped with 230 volt Franklin!/2-horsepower 3-wire motors were installed in ground water <br /> ' extraction wells EW-1,EW-2,EW-3,VW-6 and later,in monitoring well MW-1 by Clark Well,Inc <br /> of Stockton, California Each Grundfos pump was internally equipped with a one-way check valve <br /> to prevent back-flow The Grundfos pumps were installed in each well at a depth of approximately <br /> ' 30 feet below surface grade (bsg) Schedule 40, 1-inch diameter poly vinyl chloride (PVC)piping <br /> was routed from the pump to the top of the well casing and through a 6-inch diameter sanitary well <br /> seal <br /> ' In the well box at the top of the well head, a one-way check valve was installed at the outlet of the <br /> well head to prevent back-flow In the remediation area a manifold was created with independent <br />' flow meters and a copper sampling port to allow sampling of each well independently without <br /> having to remove the well head assembly <br />' 2 2 3 Installation of Ground Water Treatment System <br /> _ <br />' Three 2,000-gallon media vessels,one 1,000-gallon poly tank(holding tank),one process pump and - <br /> one sediment filter chamber were installed for the ground water treatment system Ground water <br />' Advanced GeoEnvironmental,Inc <br /> 1 <br />