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i PURPOSE AND SCOPE OF WORK The purpose of performing the hydrocarbon evaluations study is to provide conclusions as to whether the site is contaminated or is free of contamination. Our work consisted of the drilling and sampling of four test borings, classifying subsurface soil strata and laboratory testings . These borings were drilled at locations shown on Plate 2. FIELD EXPLORATION AND LABORATORY TESTING All borings were drilled with a CME-55 truck-mounted drill rig equipped with 6-inch diameter continuous hollow stem flight augers. Material encountered in each boring was visually classi- fied in the field and continuously logged by a geotechnical engineer in accordance with the Unified Soil. Classification System. Descriptions of this classification system and soils. encountered in the borings are presented on Plates 3 through 8 . All soils samples were tested in the Field with a Photovac TIP I Air Analyzer for gas and vapor. Based on the field analysis, the on-site soils appear to be "clean" . All soil samples dere obtained in accordance with guidelines setforth by the California Regional Tater Quality Control Board (CRWQCB) . These samples were later forwarded to an approved analytical laboratory for total petroleum hydrocarbons analyses. ySUBSURFACE ,OIL AND GROUNDWATER CONDITIONS A detailed description of the subsurface soil conditions encountered is presented on the Boring Logs, Plates 4 through 8, attached. In summary, the subsurface soils encountered at the site are described as brown, medium dense, silty sand with interbedded clayey sand to a maximum depth explored of 41.5 feet below existing grade. yThe near surface soils are describer) as ra dark brown to black Silty clay to a depth of 8 feet with an 8 inch asphalt pavement section covering the site. i2