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ENGEO <br /> INCORPORATED <br /> <br /> <br />5150.100.101 <br />May 2, 2008 Page 3 <br />4. FINDINGS <br /> <br />Our geotechnical field exploration was conducted on April 15, 2008. Section 2 of this report <br />presents descriptions of mapped geologic features and subsurface conditions observed during our <br />exploration. <br /> <br />4.1 REGIONAL GEOLOGY <br /> <br />The site is located in the Coast Ranges geomorphic province of California. In this part of the <br />province, bedrock is mapped as Miocene marine sedimentary sandstone by Dibblee (1980) and <br />Graymer (1994). The geologic setting of the site is depicted on the attached Regional Geologic <br />Map, Figure 3. <br /> <br />Regional bedrock structure is mapped by Dibblee (1980) striking to the northwest and dipping at <br />inclinations of about 65 to 75 degrees to the southwest. <br /> <br />4.2 SEISMIC SETTING <br /> <br />The site is located within a State of California Earthquake Fault Zone (CDMG, 1982) for the <br />Calaveras fault, as shown on Figure 4. The State mapping shows two traces of the Calaveras <br />fault crossing the site. The eastern trace is mapped by the State near the toe of the hillside, and <br />roughly parallel to Foothill Road (N25W). The State maps the northern termination of this trace <br />near Dublin Canyon Road. The second fault trace is mapped stepping to the left about 100 feet <br />to the west of the eastern trace. <br /> <br />The findings of our fault exploration were presented in a report dated March 31, 2008. Based on <br />the findings of our exploration, recommendations for building setbacks were provided as shown <br />on the attached Figure 2.