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certain whether or not the epicenters associated with the activity lie <br /> along a northeast extension of the Tracy-Stockton fault. Nevertheless, <br /> there is the possibility of an active fault capable of at least 5.0 <br /> magnitude earthquake located in or near the central part of San Joaquin <br /> County (San Joaquin County 1978) . <br /> The activity of the Midland fault is not well documented although ) <br /> there is evidence that fault displacement has occurred during recent <br /> geologic time. The maximum probable earthquake which would be generated <br /> by this fault is a magnitude of 7.0 on the Richter scale (San Joaquin <br /> County 1978) . The potential for such an earthquake is considered low <br /> (Kleinfelder 1988) . The Geotechnical Engineers at Kleinfelder concluded <br /> that there is a potential for a maximum peak bedrock acceleration as high <br /> as 0.18g based on a Richter magnitude 7.0 earthquake occurring approxi- <br /> mately 25 miles from the site on the closest point of the Midland fault. <br /> Soils <br /> The soil on the property consists primarily of Jacktone clay, which <br /> usually occurs on 0 to 2 percent slopes, is moderately deep, and is some- <br /> what poorly drained. Typically, the surface layer is very dark gray and <br /> dark gray clay about 28 inches thick. The underlying material to a depth <br /> of 34 inches is light gray clay loam. The next layer is a light gray <br /> strongly cemented to indurated hardpan about 3 inches thick. The upper 9 <br /> inches of the substratum is yellowish brown loam. The lower part to a <br /> depth of 60 inches is yellowish brown weakly cemented hardpan. Depth to <br /> hardpan ranges from 20 to 40 inches. In some areas the surface layer is <br /> silty clay or silty clay loam. The main limitations of this soil to <br /> development are high shrink-swell capacity, slow permeability, low <br /> strength, rare floodinc;, and the weakly to strongly cemented hardpan <br /> (USDA 1987) . <br /> A small portion of the project area along the middle of the south- <br /> ern boundary of the property is underlain by Clear Lake clay, which <br /> usually occurs on 0 to 2 percent slopes, is deep, and is somewhat poorly <br /> drained. Typically, the surface layer is dark gray clay about 7 inches <br /> thick. The upper 30 inches of the underlying material is dark gray clay. <br /> The next 5 inches is mixed light brownish gray and grayish brown clay <br /> 3-47 <br /> 101-44.R3 4/10/89 <br />