25B - FIRST STREET BRIDGE - Laserfiche WebLink

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Task 2.1 Traffic/Circulation Use of 2007 Traffic/Circulation Study The traffic report was completed in October 2007. The report was submitted for review to the City however, was not submitted to Caltrans. LSA proposes to submit the 2007 traffic report to Caltrans to see if it is accepted. If it is accepted by Caltrans, then the only traffic work required would be to process the traffic numbers for future 2035 conditions for the air quality and noise reports. Update or New Traffic Study (Optional Tasks) There are two approaches for a new traffic study, in the event Caltrans requires one. These include: 1. Extrapolating 2035 numbers from the existing 2007 report traffic data and updating the report with the new numbers and new traffic counts; or 2. Wholesale update including obtaining new OCTAM model numbers from the Orange County Transportation Authority (OCTA), taking new counts. Approach No. 1 can be accomplished without a tremendous amount of effort or impact on the schedule and has modest budget implications. Approach No. 2 has both major budget and schedule implications and would include basically a brand new traffic study, new counts, new model data, processing of the model data, new report preparation and review by both the City and possibly Caltrans. Task 2.2 C Air Quality (Update) The draft air quality analysis was completed in October 2007. However, the air quality report was not submitted to Caltrans because the project went on hold in February 2008. To reflect most recent changes to Caltrans Standard Environmental Reference (SER) guidelines with respect to air quality and global climate change, new and additional analysis will be required. LSA will prepare an updated Air Quality Analysis for the First Street Bridge project in accordance with the Caltrans Transportation Project Level Carbon Monoxide (CO) Protocol, the EPA's fugitive dust conformity rule, and the South Coast Air Quality Management District (SCAQMD) CEQA Handbook air quality guidelines. LSA will conduct the screening analyses specified in the CO protocol and, if required, conduct CALINE4 modeling for CO hot spots for up to 20 receptor locations for the Existing, Future No Build, and the Build Alternatives. LSA will evaluate the proposed project's impacts to long-term particulate matter concentrations (PMz.s and PMio) and mobile source air toxics (MSAT) using the Transportation Conformity Guidance for Qualitative Hot-spot Analysis in PMz.s and PMio Nonattainment and Maintenance Areas (EPA, March 2006) and the Interim Guidelines on Air Toxic Analysis in NEPA Documents (FHWA, February 2006). In addition, the proposed project's impact on global warming and climate change will be discussed. LSA will submit the particulate matter hot-spot analysis to the SCAG Transportation Conformity Working Group for review and approval. In addition to the revised air quality and particulate matter analyses, LSA will prepare the "Conformity Analysis Documentation for Project-Level Conformity Determinations in Metropolitan Nonattainment/Maintenance Areas" that is now required under NEPA delegation. 25B-6