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ME M, 01 'ME a x F '', Chevron/5. El Dorado 12 August 1990 boring locations were selected to assess the possible occurrence of concentrations of adsorbed hydrocarbons beyond the limits of they fuel tank excavation pit and to allow for the determination of the groundwater-flow direction and gradient. The borings were drilled using a truck-mounted drill rig employing 8-1/4-inch outside-diameter (O.D.) , continuous fligh". augers. Drilling was supervised by a Groundwater Technology field geologist who maintained a continuous log of the encountered materials. The M.. boreholes were continuously cored to facilitate accurate logging. Copies of the drilling logs are included in Appendix F. All three boreholes were drilled to a depth of approximately 60-feet �N below grade. Selected soil samples from the continuous core were retained for possible laboratory analyses. These samples were collected in 2-inch-diameter by 6-inch-long brass tubes. The tubes were PN sealed with aluminum foil, capped, and sealed with plastic. tape. The samples were labeled and placed on ice in an insulated cooler for transportation to the State of California-certified GTEL Environmental Laboratories, Inc. (GTEL) facility in Concord, California, under Chain-of-Custody Manifest. Copies of all applicable Groundwater Technology Standard Operating Procedures (SOPS) are included in Appendix G. Soil samples were screened in the field for volatile hydrocarbon vapors using a portable photo-ionization detector (PID) . The readings in parts per million of vapor concentration are listed on the boring logs. Soil samples submitted for laboratory analyses from each borehole were selected based on PID readin s -_----- -'-- --------- --__ -- ---g_--,_ fzeld__observation and_proxin3ty_to__the__water t.ab3e------ total of five soil samples were submitted to the laboratory and GROVNEAVATEk TECH%'OU)C5:INC.