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03/08/2006 13.31 FAX 2003/041 KLF.INFELDER We anticipate that waste disposal for each residence will be provided by an individual on-site sewage disposal system consisting of a conventional 1,200 to 1,500 gallon septic tank and leach trench disposal field. We anticipate that disposal trenches may be cut deep in order to intersect suitable percolating soils or shallow leach lines will lead to seepage pits or wells for disposal of effluent. PRESENT AND PAST USE OF THE SITE At the time of our exploration, the project site was sloping pasture land. Based on our discussions with Mr. Voorhees, we understand that the project site has been used as pasture in the past. HISTORICAL GROUNDWATER DEPTH In accordance with groundwater reports published by the San Joaquin County Flood Control and Water Conservation District (Spring 1990 to Spring 1998), high groundwater in the project area has been recorded at depths greater than 100 feet below ground surface. FIELD EXPLORATIONS AND TESTING The subsurface conditions at the site were explored on September 30, 2002 by drilling three test borings (13-1 through B-3) to depths ranging from about 20.2 to 20.8 feet below existing grade. The borings were drilled using a Simco 2400 truck-mounted drill rig equipped with 4-inch O.D. solid-stem auger. Between November 18 2002 and February 7, 2003, at least two percolation borings were drilled on each of the fifteen lots (P-1 through P-30) at depths ranging from about 3.5 to 15.4 feet below s?;e grade. The approximate boring and percolation test locations are presented on Plate 1. None of the percolation tests were performed in areas of isolated seasonal wetands as shown in plate 1. A representative with our firm maintained a log of the borings and visually classified the soils encountered according to the Unified Soil Classification System (see Plate 3). A key to the Log of Boring is presented on Plate 4 and the Log of Borings are presented on Plate 5. Based on our findings, the subsurface soils encountered consisted predominately of very-stiff, sandy to clayey silt to a depth of about 1 foot below site grade. The near- surface silts were underlain predominately by interbedded strata of medium-dense to very-dense clayey to silty sands; very-dense, cemented gravel sand; very-stiff to hard, sandy to clayey silts; and very-stiff to hard, silty to sandy clays to the depths explored. A total of thirty percolation tests were performed, two for each 2-acre lot. The percolation tests were performed in accordance with accepted guidelines using clear potable water. The procedure calls for first placing about 2 inches of fine gravel at the bottom of the bore hole. The hole is then pre-soaked with water at least 24 hours prior 231S7.G07/ST06R149 March 6.2006 Copyright 2006 Kleinfeldar,Inc. Page 2&6