2017-046 - Approving Addendum Nos. 1 and 2

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0� OCTA I Santa Ana/Garden Grove Fixed Guideway Project Noise and Vibration Technical Analysis Re-evaluation in Support of Minor Design Modifications (EA) (January 2015). The City of Santa Ana, the Lead Agency under the California Environmental Quality Act (CEQA) certified the Final Environmental Impact Record (EIR) (State Clearinghouse #2010051060) in January 2015.00TA subsequently adopted the Final EIR as a Responsible Agency under CEQA. The project has since advanced with the completion of the 30% design in May 2016. OCTA, as the agency responsible for design and implementation of the Project, is proposing design modifications to the LPA as defined in the Revised EA/Final EIR as approved by FTA and adopted by the City of Santa Ana and OCTA. The modifications comprise of physical and operational improvements, and are partly derived from value engineering and risk workshops conducted in 2015, as well as design coordination with the cities of Santa Ana and Garden Grove. The modifications are not anticipated to result in changes to the maintenance plan for the Project. Minor Design Modifications The proposed minor modifications that have been determined to have the potential to affect noise and vibration levels are presented below under the topics of proposed physical improvements and proposed operational modifications. It should be noted that OCTA does not propose to alter the underlying plans related to maintenance of the project as previously approved in 2015. The proposed minor design modifications are listed in Table 1, provided as Exhibit A to this memorandum. Physical Improvements. OCTA is proposing design modifications as part of the approved LPA that would result in the following physical improvements. These design modifications have the potential to influence noise and vibration levels and so were considered as part of the analysis: • Alignment Shift. Repositioning the double track alignment within the Pacific Electric right-of-way (PE ROW) is proposed. This modification would shift the railroad centerline within the PE ROW to the north. Attachment B provides a map of the approved alignment and the currently proposed alignment (alignment shift). • Changes to Special Trackwork. Placement of single crossovers on both sides of the maintenance and storage facility (MSF), changed layout for MSF, added crossovers on both sides of downtown couplet, and replacement of the tail track beyond the SAR Transit Center (SARTC) platform with a double -crossover before the SARTC platform. Traditional crossovers can be substantial sources of noise for receptors located within close proximity. However, the design plans call for the use of flange bearing frogs at all crossovers. The use of "well-designed" flange -bearing frogs for the special trackwork would eliminate any noise impacts. Operational Modifications. OCTA is proposing minor changes to the project's operations, which include: • Increase in Speed. Increasing the maximum speed within the PE ROW from 35 miles per hour (mph) to 45 mph; and 2