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Mitchell Drilling installed filter packs of Monterey#3 graded and washed sand around the well <br /> screens and two feet above the tops of the well screens (i e , 13 feet bgs) Prior to the installation <br /> of the well seals, Mitchell Drilling developed the filter packs by the surge and purge method The <br /> well seals consisted of two-foot layers of hydrated bentonite from approximately 11 to 13 feet bgs, <br /> and neat cement from approximately 1 to 11 feet bgs Mitchell Drilling secured the wellheads with <br /> ' watertight caps and traffic-rated, flush-mount street boxes <br /> On November 21, 2002, Morrow Surveying, a state of California licensed land surveyor (#5161) <br /> surveyed the new and existing wells The surveyor measured the elevations of the tops of the well <br /> casings to the nearest 0 01 foot, referenced to the U S C &G S Benchmark#C-958 The <br /> ' surveyor's report is included as Appendix B <br /> ' 2 2 2 Soil Sampling and Anal sis <br /> During drilling, undisturbed soil samples were collected at 5-foot intervals using a modified <br /> ' California split-spoon sampler lined with stainless steel sleeves A Ramage Environmental <br /> geologist logged all soil samples for hydrogeologic and lithologic characteristics according to the <br /> Unified Sod Classification System, and screened each sample for any organic vapors using a <br /> photoionization detector (PID) <br /> Based on field observations and in consultation with the EHD inspector, the soil samples collected <br /> at 20 and 30 feet from both monitoring well borings were selected for laboratory analysis The four <br /> soil samples were sealed with Teflon®film and plastic end caps, and transported in an iced cooler <br /> with chain-of-custody documentation to Kiff Analytical, LLC (Kifi), a state of California-certified <br /> hazardous waste testing laboratory (Certification #2236) Kiff analyzed each of the soil samples for <br /> ' TPH-as-gasoline, BTEX, MTBE, dr-isopropyl ether(DIPS), ethyl tertiary butyl ether (ETRE), tertiary <br /> amyl methyl ether (TAME), tertiary butanol (TBA), and 1,2-dichloroethane (1,2-DCA) by EPA <br /> Method 8260B <br /> 2 2 3 Groundwater Monitoring, Sampling and Analysis <br /> On December 19, 2002, Ramage Environmental monitored and sampled the two new and four <br /> existing monitoring wells and the one on-site domestic water supply well Depth-to-groundwater <br /> was monitored using a water level indicator capable of measurements to within 0 01 foot Following <br /> groundwater level measurements, the wells were purged and sampled <br /> 9 <br />