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r The three borings were drilled by Woodward Drilling Company of Rio Vista, California. Woodward utilized a Mobile B-57, truck-mounted drilling rig equipped with a 10-inch O.D., hollow-stemmed auger. All drilling equipment was thoroughly steam-cleaned prior to -_ drilling in order to prevent contamination from off-site sources, and also between borings to prevent cross-contamination. 3.2 Soil Sampling Undisturbed soil samples were collected at 5-foot intervals to 25 feet bsg in each j boring/well during drilling operations in order to identify the soil types within the vadose (unsaturated) and water-bearing (saturated) zones. Samples from 5, 10, 15, and 20 feet bsg were submitted for analysis. Samples from 25 feet bsg were completely water-saturated and not suitable for analysis. =' Soil samples were logged by the W.W. Irwin, Inc. field geologist using the Unified Soil Classification System (USCS). The depths at which the water table was encountered were noted on all boring logs, which are included as Appendix B. The stratigraphy penetrated j: when advancing the borings consisted of primarily of black-gray, organic, clayey silts. Cuttings have been stored in 55-gallon capacity drums for later treatment and/or disposal at the discretion of Village West Marina management. "' The soil samples were collected by driving a two-inch diameter, California-modified split- spoon sampler utilizing a 140-pound hammer from a rig height of 30 inches (per ASTM Standard 1586). Blow counts required to obtain each sample were recorded on the respective boring logs. Upon opening the sampler, the ends of one of three of the brass sample tubes were immediately sealed with TeflonT"" liners, capped with polyethylene end =_ caps, and final-sealed with polyethylene tape. 3.3 Analytical Results A Each sealed tube was properly labeled and placed in a cooler chilled to 4°C for transport to Sherwood Labs Corporation in Hilmar, a California Department of Health Services (DHS) -certified laboratory. Soil sampling and handling were conducted using appropriate chain-of- custody procedures. Each sample collected to a depth of 20 feet was analyzed for the presence of Total Petroleum Hydrocarbons as gasoline (TPH-g) by modified EPA Method 8015/5030,Total Recoverable Petroleum Hydrocarbons as diesel(TRPH-d),and the volatile aromatics benzene, toluene, ethylbenzene, and total xylenes (BTEX) by EPA Method 8020. All soil analytical results are listed in Table 1. The laboratory reports and accompanying chain-of-custody are included as Appendix D. ;j Detectable,primarily fractional BTEX analytes were detected only in soil samples collected from MW-6. The highest TPH-g result was 39 mg/kg, revealed in the sample collected from MW-6 at 15 feet bsg. TRPH-d results were nondetectable except for 8 mg/kg of weathered W.W.Irwin,Inc. Project No.33016.03 July 1994 4 _�l