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Manteca Unified School District Subsurface Soil&Groundwater Investigation former diesel dispenser (Figure 2). A maximum of three soil samples will be collected at various depths and will include soil the groundwater interface. Since groundwater has been identified in the area at about 20 feet in depth, a water sample will be obtained prior to termination of each boring. Samples will be analyzed by GeoAnalytical Laboratories for diesel & BTEX. A report of the subsurface investigation containing scaled site map, boring logs, and soil and groundwater sampling records with laboratory data sheets will be prepared at the end of this phase of work. All work will be certified as conducted under the direct supervision of a licensed professional. 2.1 Drilling Permits.will be obtained, if necessary, for the borings before drilling begins. The soil boring will be accomplished using a mobile mounted Geoprobe® Systems drilling rig, Model 5400, employing the use of a 1.25"hollow probe rods. The contractor conducting the drilling will posses a valid C-57 license and proof of workman's compensation insurance. All drilling equipment will be thoroughly steam cleaned before drilling begins to prevent the introduction of contamination from off site, and between borings to prevent cross contamination. The borings will be 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 will be noted. All water-bearing zones and the depths at which they are encountered will be noted on these logs. All borings will be drilled in such a manner as to prevent cross contamination between strata. Water samples will be taken at the soil/groundwater interface (if encountered), and the borings will then be terminated with a cement and three percent (3%)Bentonite mixture. 2.2 Soil Sampling All soil sampling equipment will be thoroughly steam cleaned before and between sampling to prevent cross contamination. Relatively undisturbed soil samples will be taken at intervals of not more than five feet (5') in order to evaluate the subsurface materials. The soil samples will be taken using a Geoprobe® core sampler with plastic liners. The sampler will be pushed (Direct Push Technology) continuously by the hydraulically powered, percussion system. 2