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Cef4Z ALL eco w 2 of 6 Pages The materials penetrated in our borings are chiefly clay , silty Clay and clayey silt . Sandy strata , although present , are relatively minor and are silty or clayey and fine-grained . Bedding is absent or nondi. stinet but appears to be essentially horizontal . Owing to a moderate to high silt and/or fine- P. rained sand conte.. t , the clays are not highly plastic . Permeability of the clays and silts is low whereas the sands exhibit somewhat higher permeability . The Modesto Formation is known to be underlain by , older Pleistocene and Tertiary strata which in turn rest on crystalline basement , However , these formations are of no significance to this pvesant study because of their depth . No faulting or fracturing is evident on or near this site . HYDROLOGY Owing to the fine-grained character of the sediments here the Position of the water table was difficult to determine during drilling but post drilling measurements show the static level to be about 44 feet below ground elevation . Free moisture on core samples was apparent beginning at about 35 feet in all holes , The water table at this time slopes very gently north westward . However , regional trends , especially during summer months when there is considerable pumping east of Stockton are easterly . Published data show a fluctuation of 10 feet or more from season to season , for example in the spring of 1966 the water table here was less than 30 feet deep ( See Ground Water and Hydraulic Maps in Annex ) . Owing to hydrologic and geologic features described above it seems likely that horizontal movement of ground water , and any contaminant , is very slow , Two municipal wells are located ,just over 1 /4 of a mile from the site . Well Eta • 30 is at the Corner of American and Taylor and it 2100 Feet from the' site . Well Sta 50 is located at the corner of Wilson Way and Clay about 2200 Feet from this site . We understand the wells are pumping from deep aquifers and do not tap the ground water we are investigating . _ SAMPLING Borehole samples were taken every 5 Feet during drilling . of these samples were sent to the California Water Lab in Most Modesto , The results of the soil samples are given in Table 1 . Water samples were obtained using a clean bailer and decanted into VOA Vials supplied by the laboratory , The results of this sampling are shorn in fable 2 .