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1 1 Report of Findings • Frontier Transportation ' 03-28-98 March 28, 1998 of grout to near ground surface. A lockable flush-mount protective casing was set over each well top and surrounded by a surface seal of concrete. ' The riser and screen was constructed of two-inch inside diameter, schedule 40 polyvinyl chloride (PVC) pipe. Slotted PVC was extended from approximately 6' bg to termination depth and it contained three rows of 0.010-inch slots. Ends of the screen and riser sections were constructed with flush joining threaded fittings to ensure leak-proof unions. A filter pack of sand was placed around the screen to retain the finer grained fractions of formation material and to create a zone of high permeability that allows free entry of water in the well. The pack consisted ' of clean quartz Monterey#3 sand. ' The annular seal was necessary to prevent the annulus from serving as a vertical conduit for potential contaminants. The annular seal was composed of a mixture of one 94 pound bag of Portland cement mixed with 5-10 gallons of potable water. Following placement of the annular ' seal, a large-diameter flush-mount protective casing was installed around each well head. The casing was firmly seated in concrete and supplied with lockable covers for security (See Appendix B for Well Completion Data). ' All work was performed per California Regional Water Quality Control Board (CRWQCB) guidelines under the supervision of California Registered Civil Engineer with more ' than ten years experience in the environmental field. Drillers possessed a California State C-57 Contractors License. All soil cuttings and development water were properly containerized, labeled and stored on-site in DOT approved 17-H 55-gallon drums for disposal at a later date. 5.0) SOIL SAMPLE RESULTS Soil samples were collected every five feet to termination depth from each well boring. All soil samples were collected through the auger using a split-barrel sampling device. The sampler was lined with three, 6-inch long, 2-inch diameter brass sampling rings to contain the soil ' which was immediately be sealed with Teflon tape, capped and packaged using a PID to detect volatile organic compounds. The rings were examined for physical evidence of contamination and for soil classification. Soil samples were transported in an ice chest under chain-of-custody ' protocol to Applied P & Ch Laboratory (CADHS ELAP No.: 1431). Samples were analyzed for TPH-d, TPH-gas, and BTEX (Benzene, Toluene, Ethylbenzene, and Xylene) including MTBE using EPA methods 8015 modified for gasoline, 8015 modified for diesel and 8020, respectively. ' - Soil sample analysis results are presented in Table 4 and laboratory analytical reports are included - in Appendix C. • 5