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603284-001 <br />APPENDIX E <br />Liquefaction Analvsis <br />Methodology <br />Leighton evaluated the liquefaction potential at the site using data obtained from Cone <br />Penetration Testing (CPTs), CPT-1 through CPT-6, advanced to approximately 100 feet <br />below existing ground surface (bgs). The analyses were performed using the computer <br />program CLiq Version 1.5.1.16 (Geologismiki, 2006). Our analyses are generally based <br />on the procedures outlined in Guidelines for Evaluating and Mitigation Seismic Hazards <br />in California (Special Publication 117A)published by the California Geological Survey <br />and Recommended Procedures for Implementation of DMG Special Publication 117 <br />Guidelines for Analyzing and Mitigating Liquefaction in California published by the <br />Southern California Earthquake Center (SCEC). <br />Groundwater was encountered at depth of 25.5 feet below existing ground surface <br />during our geotechnical exploration. According to the California Division of Mines and <br />Geology 1997 Seismic Hazards Zone Report for the Anaheim and Newport Beach <br />Quadrangle, Open File Report 03, historical high groundwater elevations at the site are <br />as shallow as 15 feet below ground surface (bgs). We have performed analyses using <br />historic high groundwater level of 15 feet bgs. <br />Discussion of Results <br />The site is located within an area of liquefaction according to the State of California <br />Seismic Hazards Zones Map for the Anaheim Quadrangle. Our analyses indicate that <br />the site is generally classified as having low risk of liquefaction based on the liquefaction <br />potential index (lwasaki et al., 1978). Liquefaction potential index (LPI) combines depth, <br />thickness, and factor of safety of liquefiable material inferred from a cone penetrometer <br />test (CPT) sounding into a single parameter. The LPI ranges from 1 to 2.5. LPI values <br />lower than 5 are deemed low risk. <br />The potential for liquefaction are the site is generally confined within thin layers at <br />depths ranging from about 20 to 50 feet bgs. The results of our liquefaction analyses <br />are included in Appendix E, Liquefaction Analysis. <br />The seismically-induced settlement resulting from the design event is estimated to be in <br />the order of 1 to 2 inches. Differential settlement is estimated to be approximately M <br />inch over 100 feet. The results of our analyses are presented at the end of this <br />appendix. <br />E-1