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Project No. JB -314 <br />24 March 2003 <br />Page 3 <br />subject property is approximately 150 feet long and 150 feet wide and is bounded <br />by Pacific Avenue to the east and Douglas Boulevard to the south. The site <br />partially paved and drains to the streets and on-site drain inlets. <br />3.2 Subsurface <br />Fill was not encountered in the borings at the time of drilling. There may be fill <br />in areas beyond or between our exploratory borings. In general, the native soils <br />consisted of medium stiff to very stiff silty clay and dense clayey sand. <br />Laboratory testing indicates that the near -surface soils have a high expansion <br />potential. <br />Groundwater was not encountered in the borings at the time of drilling. We <br />expect groundwater levels to fluctuate due to variations in rainfall, groundwater <br />recharge, and site conditions. <br />4.0 SEISMIC AND LIQUEFACTION CONSIDERATIONS <br />4.1 Seismic <br />Geologic references indicate that no fault trace designated active or potentially <br />active passes through the subject property. The only active fault within 15 <br />kilometers of the site is the Hayward Fault. Table 1 lists the distance from the <br />fault, the maximum moment magnitude, the slip rate, and fault type for local <br />faults. The subject site is located in Zone 4 as defined by the Uniform Building <br />Code (1997 edition) on Figure 16-3, Seismic Zone Map of the United States. <br />Based on the soils encountered in the borings the most appropriate Soil Profile <br />Type would be So. <br />Table 1 <br />ACTIVE FAULTS AND CHARACTERISTICS <br />Fault Distance' <br />ME' <br />Slip Rate' <br />Fault Type' <br />(km) <br />(mm/yr) <br />Greenville 28 <br />6.9 <br />2.00 <br />B <br />Calaveras (north) 40 <br />6.8 <br />6.00 <br />B <br />Hayward (south) 48 <br />6.9 <br />9.00 <br />A <br />San Andreas (peninsula) 66 <br />7.1 <br />17.00 <br />A <br />1. CDMG, Maps of Known Active Fault, Near -Source <br />Zones in California and Adjacent <br />Portions of Nevada, 1997. <br />2. CDMG, Probabilistic Seismic Hazard Assessment for <br />the State of California, 1996. <br />4.2 Liquefaction <br />It is our opinion, based on the soil conditions encountered in the boring logs, that <br />WKorbmthesite-nsods have a low potential of soil liquefaction. <br />