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Alliance Residence October 18,2016 J.N.: 2530.00 Page 7 Tabulated summary of our liquefaction analyses are provided on Plates C-1 through C-14 in Appendix C. Soils with corrected blow counts greater than 30 per foot or corrected CPT tip resistance greater than or equal to 160 tons per square foot (tsf) were assumed to be not susceptible to liquefaction. Based on our analyses, a number of thin layers mostly between depths of 30 and 50 feet, and occasionally as shallow as approximately depth 10 feet, that are separated by thick sequences of clayey soils have factors of safety below 1.3. Therefore, some limited thin layers are prone to liquefaction during the design earthquake event. Analyses were performed to evaluate the potential magnitude of settlement resulting from liquefaction of the layers with a liquefaction safety factor less than 1.3. The estimated settlement caused by soil liquefaction was evaluated for the site based on the empirical procedures developed by Tokimatsu and Seed (1987) and Ishihara and Yoshimine (1992) which cdmpare the volumetric strain in the soil with the induced cyclic stress ratios/liquefaction safety factors. Taking the average of these two methods, we estimate maximum settlement ranging from about 0 to 0.8 inches. Liquefaction induced-settlement analyses are provided in Appendix C on Plates C-15 through C-28. 5.0 CONCLUSIONS 5.1 FEASIBILITY OF PROPOSED DEVELOPMENT From a geotechnical point of view, the proposed site development is considered feasible provided the development is designed and constructed in accordance with the recommendations presented in this report. 5.2 SEISMIC HAZARDS 5.2.1 Ground Rupture No active faults are known to project through the site nor does the site lie within the bounds of an "Earthquake Fault Zone" as defined by the State o f Cali fornia in the Alquist-Priolo Earthquake Fault Zoning Act. As such, the potential for ground rupture due to a fault displacement beneath the site is considered very low. 5.2.2 Ground Shaking The site is situated in a seismically active area that has historically been affected by generally moderate to occasionally high levels of ground motion. The site lies in relative close proximity to several active faults; therefore, during the life of the proposed improvements, the property will probably experience similar moderate to occasionally high ground shaking from these fault zones, as well as some background shaking from other seismically active areas of the Southern California region. Potential ground accelerations have been estimated for the site and are presented in Section 4.1 of this report. Design and construction in accordance with the current California Building Code (CBC) requirements is anticipated to address the issues related to potential ground shaking. ALBUS-KEEFE & ASSOCIATES, INC.