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ENGEO INCORPORATED 5150.100.101 March 31, 2008 5 the site. To the south of the site, the hill front forms a linear feature that is parallel to Foothill Road and to the main trace of the Calaveras fault. Field Exploration Our field exploration included excavating and logging three exploratory trenches totaling approximately 226 lineal feet. The trenches were excavated using a tractor-mounted backhoe on February 28 and March 1, 2001, and ranged from about 6 to 14 feet deep. The trenches were shored to permit safe entry and were logged by Mr. Raymond Skinner, an Engineering Geologist from ENGEO. The trench locations are shown on Figure 2 and logs of the trenches are presented in Appendix A. The trenches were located by tape measuring distances from the driveway and fences shown on the topographic base map. On March 1, 2001, Mr. Dale Marcum and Mr. Ted Sayer from Cotton, Shires & Associates (Geotechnical Reviewer for the city of Pleasanton) were on-site and examined conditions exposed in Trenches T-1, T-2, and T-3. The trenches were backfilled on March 2, 2001, with nominal compactive effort. Trenches within the development area that are not completely removed by design cuts will require overexcavation and recompaction during site grading. Conditions encountered in our exploratory trenches are summarized below. Trench T-1 From Stations 0+00 to 1+20, interbedded siltstone, sandstone, and conglomerate were encountered. Bedrock structure was observed striking N10E to N25W and dipping 60 to 75 degrees to the east. Colluvial soil deposits thickened abruptly at about Station 1+20, and at Station 1+25 were greater than 14 feet thick. Due to groundwater seepage and caving trench walls, the trench was terminated at about Station 1+32. No shearing or other features indicative of faulting were observed.