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In each well, a filter pack of#2112 graded and washed silica sand was placed through the hollow stem augers as they were slowly retrieved and until the sand pack reached approximately two feet above the top of the screened interval Following the placement of the sand packs, the driller developed each of the wells by the surge and purge method Each of the wells was surged for approximately 5 minutes using a wire-line surge block system Between surging cycles, approximately 5 gallons of groundwater were bailed from each well Following well development, two feet of hydrated bentonite chips were placed within the annular space between the borehole and the well casing A surface seal of neat cement grout was placed over the hydrated bentonite, under PHSIEHD observation The tops of the wells were secured with water-tight locking caps and 8-inch diameter, traffic-rated utility boxes During October 2000, Morrow Surveying (California Licensed Land Surveyor#5161) surveyed each of the newly-installed wellheads Morrow Surveying located each of the wells and measured the elevations of the tops of each well casing to the nearest 0 01 foot, referenced to an assumed elevation of 100 00 feet above mean sea level (msl) A benchmark was not available in the site vicinity The surveyor's report is included as Appendix B 2 2 2 Soil Sampling and Analysis During drilling,, soil samples were collected at five-foot intervals using a modified California split- spoon sampler lined with 2-inch diameter by 6-inch long brass or stainless steel sleeves A field geologist logged each of the soil samples for geologic and hydrogeologEc characteristics and screened each sample with an organic vapor monitor, equipped with a photoionization detector (PID) The monitoring well logs with well construction diagrams and PID measurements are included as Appendix C To further evaluate the extent of impacted soil, the soil samples collected at 15, 25 and 80 feet bgs from all three soil borings, at 40 feet bgs from the boring for MW-2, and at 60 feet bgs from the borings for MW-1 and MW-3 were submitted for laboratory analysis These soil samples were sealed with Teflon®film and plastic end caps, labeled, and transported in an iced cooler with chain-of-custody documentation to Kiff Analytical, LLC (Kiff), a state of California certified rhazardous waste testing laboratory (Certification #2236) Kiff analyzed each of the soil samples for TPH-as-gasoline, BTEX, MTBE, DIPE, ETBE, TAME, TBA, and 1,2-DCA by EPA Method 8260B 10