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BUSINESS OFFICES Fax 209-9432611 Apr 23 1746 0+11fIROSEMCH ;!P.O. aunt mar !�*VOMTM, IG► 95M toolm 403s-anlal! The formation primarily encountered is the older alluvium of the Pleistocene and Holocene ages to recent Quaternary fills. The depth of these older alluvial sediments is estimated to be approximately 200 feet this within the area of the site. Underlying the older alluvium are continental deposits of Pliocene and Pleistocene age. The recent fills have been placed there by recent human activity and range in depth form 1 to 6 feet. Locally, the site is underlain by the Riverbank Formation which is described by the United States Geological Survey (U S.G.S.) San lose Sheet as brown to gray -red locally Pebbly, with minor silt and clay on the east side of the Saa Joaquin Walley. Unconsolidated Pleistocene, Nan -Marine, Sedimentary deposits blanket the ;.:: surrounding area. Locally, the deposits are called the riverbank formation and Aromas Red Sands which consist of brown to gray, red to yellow crossbedded sands, locally pebbly with mipor amounts of silt and clay. The surface geology consists of recent alluvial deposits chiefly composed of a tan to brown - silty sand with gravel and clay. 3.3 HYQ OLOGY The unconsolidated deposit (upper 700 • 900 feet) contain several water producing zones.. Fluctuations in the water table elevation are the result of local pumping and seasonal Of I041 variations in rainfall and stream discharge. The depth to groundwater in the site vicinity is approximately 45 to 50 feet below grade. Reports in the site vicinity indicate that the general groundwater flow direction is Westerly. i'." The distribution of groundwater is directly related to the geology and the 1 enYlrnatmentl in which they were deposited. The unconfined water body occurs in the unconsolidated deposits above and East of theE•cley, except in the Western and Southern parts of the area where clay lenses occur and