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Lincoln Avenue Podestrian Pathway Connectivity I Park Lane to Santiago Creek utility poles, and other features needed for site design. The survey will include, at a minimum data at 20 foot cross sections along the corridor of the project and at begin, end and any other significant grade features. Tetra Tech understands that work around active railroad can be extremely dangerous. To mitigate this situation, Tetra Tech proposes to use our scanning total station to capture data over the rail track area. Our scanning total station is able to collect point cloud data, to a design level accuracy, while remaining well off the track area. Point cloud data would be "ground truthed" with a limited number of traditional topographic survey shots on rail facilities, drastically reducing the lime that our field crews are In danger of the active railway, and minimizing any disruption to rail operations. Survey control will be tied horizontally to the North American Datum of 1883 (NAD83) through GPS post processing constrained to the California Spatial References Center, Epoch 2017 Control. Vertical control will be tied to the North American Vertical Datum of 1988 (NAVD88) by occupation of the nearest City of Santa Ana or NGS benchmark controlled by that datum. If the benchmark used is not within site distance of the project a local survey benchmark will be established for use during construction. The Property Line surveys will be performed to establish the locations of the private properties, the City of Santa Ana Right of Way and the Metorlink Railroad Right of Way In the vicinity of the project. Sufficient boundary monumentation will be recovered to orient a survey boundary, compiled from record documents for the project. Additional easements or agreements provided to Tetra Tech by the City of Santa Ana that exist foe the railroad will also be plotted. A full boundary establishment survey is not believed to be necessary and is not Included at this time. A Survey base file drawing including property lines, survey control and topographic data will be prepared. Electronic files will be generated In Microstation V81 format using US Customary Units. All survey work will be performed under the guidance and responsible charge of a Land Surveyor licensed in the State of California. ENVIRONMENTAL CLEARANCE DOCUMENTS & REPORTS Tetra Tech will develop a revised project description based on the current project and will review the CEQA CE that was previously filed for adequacy. The results will be documented in a letter report. Tetra Tech understands this pathway was referred to in the prior environmental document which resulted in the closure of pedestrian and bicycle access at the prior At -grade Railroad Crossing at Fairhaven Avenue. Although it was not listed as a specific mitigation required of the closure, it was understood in prior project's environmental document that a future pathway would be required to restore access for pedestrians and bicyclists as a result of the full at -grade crossing closure, Prior outreach was conducted with the community about the need for this pathway approximately six years ago. Given this history, Tetra Tech will provide practical recommendations for any remaining environmental documentation (CEQA) steps that should be conducted. If needed, Tetra Tech will Identify additional environmental analysis and/ or environmental -related grant -funded paperwork required for this ATP project. GEOTECHNiCAL Our team will review and summarize available Information regarding local conditions for the site surrounding areas Including geologic maps and other published reports that may aid in identifying geologic risks, To characterize surface and subsurface conditions In order to provide design requirements for structural improvements, we will drill three (3) hollow stem auger borings to depths between 10 and 15 feet and two (2) hand auger borings to depths of 2 feet. poring locations will be and notify you and Underground Service Alert (USA) prior to beginning fieldwork so that public or private underground utilities can be identified. Percolation tests will be done in four locations, two at the 2 foot depths and two at 10 foot depths to TETRATECH 23