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EXHIBIT 2 <br /> Earth Mechanics Inc. <br /> Geotechnical & Earthquake Engineering <br /> TECHNICAL MEMORANDUM <br /> EMI PROJECT NO: 11-123 <br /> DATE: September 13, 2011 <br /> PREPARED FOR: Mohan Char, Ph.D., P.E. /AECOM <br /> PREPARED BY: Ranjan Gunaranjan and Lino Cheang /Earth Mechanics, Inc. (EMI) <br /> SUBJECT: Santa Ana Boulevard Grade Separation <br /> City of Santa Ana, Orange County, California <br /> Structure Preliminary Geotechnical Report (SPGR) <br /> Introduction <br /> This memorandum has been prepared to provide the necessary geotechnical information to assist <br /> the structural designers in the type selection process for the Santa Ana Boulevard Grade <br /> Separation (GS) at Santa Ana Boulevard and Metrolink Railroad intersection. The content of this <br /> memorandum follows Caltrans Foundation Report Preparation for Bridge Foundations (Caltrans, <br /> 2009). It includes preliminary geotechnical, seismic, and foundation recommendations for the <br /> subject GS and the adjoining retaining walls. The recommendations provided in this <br /> memorandum are based on subsurface information contained on the as-built Log-of-Test-Borings <br /> (LOTB) of three nearby structures: Grand Avenue Undercrossing (Bridge No. 55-671L), Lincoln <br /> Avenue Underpass (Bridge No. 55-672), and Lincoln Avenue Overcrossing (Bridge No. 55-675). <br /> These nearby bridges are located less than 0.3 mile from the proposed GS. An additional <br /> geotechnical investigation will need to be performed during the PS&E phase; therefore, the <br /> following recommendations may change when additional information becomes available. <br /> Project Description <br /> As presented in the preliminary plan provided by the designers, the existing Santa Ana <br /> Boulevard, which intersects at-grade with the existing Metrolink railroad tracks, will be lowered <br /> under the railroad tracks to have a minimum vertical clearance of about 16.5 feet. The horizontal <br /> alignment of Santa Ana Boulevard will also be shifted about 30 feet to the south due to the <br /> presence of a utility corridor. Retaining walls will be constructed on the north side of the Santa <br /> Ana Boulevard in-line with the bridge abutment (Abutment 5). A portion of the retaining wall <br /> located at the depressed roadway is proposed to be a Type SW retaining wall and the remaining <br /> portion is proposed to be Caltrans Standard Type I retaining wall. Based on the information <br /> provided by the structural designers, Type SW retaining wall is a U-shape cantilever wall that <br /> will support the sidewalk in the middle of the "U". <br /> 17800 Newhope Street,Suite B,Fountain Valley,California 92708. Tel: (714)751-3826,Fax: (714)751-3928 <br />