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Between September 9th and September 13f 1994 we drilled three <br /> p p <br /> additional wells at this site. The wells were drilled to a <br /> depth of 65 feet and 2 inch Schedule 40 PVC slotted (0 . 02) <br /> casing was placed from the well bottom upward 20 feet. The <br /> remaining casing was 2" blank schedule 40 PVC and was placed <br /> to the surface. Number 3 sand was placed opposite the slotted <br /> section and about 20 feet above the last slot. Then the <br /> annulus was filled with hydrated bentonite for 3 feet and the <br /> Iremainder of the annulus was sealed with neat cement. A <br /> traffic box was placed over the well and cemented to the <br /> Ipavement. (See Well Logs. ) <br /> The wells were developed by removing approximately 70 gallons of <br /> water at which time the sediment was greatly reduced. <br /> Approximately 24 to 48 hours later, the wells were surveyed, <br /> with a spirit level , to tie the tops of the casings to the local <br /> datum, measured for depth to water and sampled. ( See <br /> Protocols) <br />' SITE CHARACTERIZATION <br /> GEOLOGY <br />' The site and all nearby terrain are underlain by non-marine <br /> fine--grained sediments, which are tentatively assigned to the <br /> Modesto Formation of Pleistocene Age. (USGS Bulletin 1470 <br /> Marchand and Alwordt, 1981) . Although the Modesto Formation is <br />' typically composed of coarser--grained material such as sands and <br /> gravels, it is reasonable, on the basis of stratigraphic <br />' position, to consider these finer-grained sediments to be the <br /> distal portion of the large alluvial fans which make up the <br /> Modesto Formation. <br /> The materials penetrated in our borings are chiefly clay, silty <br /> clay and clayey silt. Sandy strata, although present, are <br /> relatively minor and are silty or clayey and fine-grained. <br />' Page 4 <br />