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' Pombo Property Soil & Groundwater Sampling . 2.1 Drilling ' Permits were obtained for the borings before drilling began. The soil borings were accomplished using a mobile mounted Geoprobe' Systems drilling rig, Model 5400, employing the use of a 1.25"hollow probe rods. All drilling equipment was thoroughly cleaned before drilling began to prevent the introduction of contamination from off site, and between borings to prevent cross ' contamination. The borings were logged under the direct supervision of a registered geologist using ' the Unified Soil Classification System. The color, texture, moisture, plasticity (if applicable), consistency of the earth materials, pertinent soil or bedrock ' characteristics, and any evidence of contamination were noted. All water-bearing zones and the depths at which they were encountered are noted on these logs. ' All borings were drilled in such a manner as to prevent cross contamination between strata. Water samples were taken five feet below the soil/groundwater interface, and the borings were then terminated with a cement and three percent Bentonite mixture. 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 Geoprobe' core sampler with plastic liners. The sampler was pushed (Direct Push Technology) continuously by the k i hydraulically powered percussion system. ' The laboratory samples did not have headspace and were immediately sealed in their liners using plastic caps. The remaining sample was removed from its liner to ' be used as an aide to the on-site geologist in logging the material at that depth. ,t Soil samples were collected at five-foot intervals for geological interpretation and laboratory analysis (I to 2 laboratory soil samples per boring). All soil samples were delivered, under chain of custody, to GeoAnalyticai Laboratories, an ' analytical laboratory licensed by the State of California for hazardous materials work. The samples were analyzed for Total Petroleum Hydrocarbons (gasoline & diesel), BTX&E (Benzene, Toluene, Xylene, and Ethyl Benzene) and MTBE by ' method 8020. Laboratory analyses of the Organophosphate group and Chlorinated . Pesticides, EPA Methods 8140 and 8080, were conducted on selected samples. All rinse water was removed by the driller, V&W Drilling, Inc. Drill cuttings are ' not produced by this method. 1 3 r