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1 <br /> In each well, a filter pack of#3 graded and washed silica sand was placed through the hollow <br /> ' stem augers as they were slowly retrieved and until the sand pack reached approximately two feet <br /> above the tops of the screened intervals Following the placement of the sand packs, the driller <br /> developed each of the wells by the surge and purge method Each of the wells was surged for <br /> approximately 5 minutes using a wire-line surge block system Between surging cycles, <br /> approximately 5 gallons of groundwater were bailed from each well Following well development, <br /> one foot of hydrated bentonite chips were placed within the annular space between the borehole <br /> and the well casing A surface seal of neat cement grout was placed over the hydrated bentonite, <br /> ' under PHSIEHD observation The tops of the wells were secured with water-tight locking caps <br /> and 8-inch diameter, traffic-rated utility boxes <br /> ' During January 2001, Morrow Surveying (California Licensed Land Surveyor#5161) surveyed <br /> each of the newly-installed wellheads Morrow Surveying located each of the wells and measured <br /> the elevation of the top of each well casing to the nearest 0 01 foot, referenced to Manteca <br /> Benchmark #63 (Elevation 33 76 feet) The surveyor's report is included as Appendix B <br /> ' 2 2 2 Soil Sampling-and Analysis <br /> During drilling, soil samples were collected at five-foot intervals using a modified California split- <br /> spoon sampler lined with 2-inch diameter by 6-inch long brass or stainless steel sleeves A field <br /> geologist logged each of the soil samples for geologic and hydrogeologic characteristics and <br /> screened each sample with an organic vapor monitor, equipped with a photoionization detector <br /> (PID) The monitoring well logs with well construction diagrams and PID measurements are <br /> ' included as Appendix C <br /> To further evaluate the extent of impacted soil, the soil samples collected at 20 and 25 feet bgs <br /> ' from the soil borings for MW-1 and MW-2 were submitted for laboratory analysis These soil <br /> samples were sealed with Teflon®film and plastic end caps, labeled, and transported in an iced <br /> ' cooler with chain-of-custody documentation to Kiff Analytical, LLC (Kiff), a state of California <br /> certified hazardous waste testing laboratory (Certification#2236) <br /> Kiff analyzed each of the soil samples for TPH-as-diesel by EPA Method 8015M, and for TPH-as- <br /> gasoline, BTEX, MTBE, DIPS, ETRE, TAME, TBA, and 1,2-dichloroethane (1,2-DCA) by EPA <br /> ' Method 8260B <br /> 9 <br />