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McDowell&Davis Towing Subsurface Soil Investigation All borings were drilled in such a manner as to prevent cross contamination between strata and terminated with cement. 2.2 Soil Sampling All soil sampling equipment was thoroughly steam cleaned before and between sampling to prevent cross contamination. Relatively undisturbed soil samples were taken at intervals of not more than five feet (5') in order to evaluate the subsurface materials. The soil samples were taken using a California Modified Split Spoon sampler with brass liners. The sampler was driven by a 140 pound hammer repeatedly falling 30 inches drove the sampler. The blow counts necessary to drive the sampler were recorded for each 6-inch interval to help evaluate the consistencies of the materials. The laboratory samples did not have head space and were immediately sealed in their liners using aluminum foil lined plastic caps. The remaining sample was removed from its liner and used as an aide to the on-site geologist in logging the material at that depth. Soil samples were collected at five foot intervals for geological interpretation and laboratory analysis (1 laboratory soil sample per boring). All soil samples were delivered, under chain of custody, to an analytical laboratory licensed by the State of California for hazardous materials work. The samples were analyzed for Total Petroleum Hydrocarbons (gasoline), MTBE and BTX&E (Benzene, Toluene, Xylene, and Ethyl Benzene) by method 8020. Bottom hole samples included analysis for the Oxygenated Compounds by Method 8260. Analyses were conducted by GeoAnalytical Laboratories, Inc., in Modesto, California. All rinse water was containerized and stored on site. The drill cuttings were stockpiled on plastic and are the responsibility of the property owner. 3.0 SOIL CONDITIONS 3.1 Site Geology & Stratigraphy Sands of the Pliestocene Modesto Formation dominate soils geology at the site. The sands vary in color from red-brown to grey and in USCS classification from SP — poorly graded to SM — silty sands. The dominant grain size is fine to very fine-, some units include sparse coarse grains, these units are skip-graded. Sand grains are angular to sub-rounded; mineralogy is arkosic with numerous grains of phologopite mica. These characteristics are typical of facies deposited in the distal portions of the Ancestral Stanislaus River alluvial fan/delta system. 3