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1 r Following the placement of the sand pack, Mitchell Drilling developed the well by the surge and Purge method The well was surged for approximately 5 minutes using a wire-line surge block system Between surging cycles, approximately 5 gallons of groundwater were bailed from the ' well Following well development, three 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 PHS/EHD observation The top of the well was secured with a water-tight locking cap and an 8-inch diameter, traffic-rated utility box During December 2001, Morrow Surveying (California Licensed Land Surveyor#5161) surveyed the newly-installed well into the existing monitoring well network Morrow Surveying located the well and measured the elevation of the top of the well casing to the nearest 0 01 foot, referenced rto 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 r2. 2 2 Sod Sampling and Analysis ' During drilling, sod samples were collected at five-foot intervals using a modified California split- spoon sampler lined with 2-inch diameter by 6-inch long stainless steel sleeves A Ramage Environmental field geologist logged each of the sod samples for geologic and hydrogeologic characteristics and screened each sample for organic vapors using a photolonization detector (PID) The monitoring well log with a well construction diagram and PID measurements is included as Appendix C r To further evaluate the extent of impacted soil, the soil samples collected at 70, 75 and 85 feet bgs were submitted for laboratory analysis These sod 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 hazardous 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 2 2 3 Groundwater Monitoring, Sampling and Analysis r On December 17, 2001, Ramage Environmental monitored and sampled groundwater from the new well and the three existing wells Upon arrival at the site, each of the wellheads was inspected, unlocked and opened Depth-to-groundwater was measured in each of the wells using a water level indicator capable of measuring groundwater to within 0 01 foot r • 12 r