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Page 13 of 65 Tree Survey A tree survey, created by a professional arborist, will identify significant trees (up to 600 trees of 12-inch diameter or greater) throughout Sub-Area 1, so that trees in good health are considered development constraints and preservation is incorporated in the Development Plan when feasible. The arborist will prepare a memo summarizing survey methodology and findings to accompany the survey. B.Geotechnical Review (funded by MTC PSTA Task 2.b) Supported by MTC Priority Sites Technical Assistance funding, a high-level cursory review of existing geologic and geotechnical data will be prepared based on historic geotechnical reports provided by City, County, BART and/or Property Owners. The goal is to identify any hazards (e.g. fault zones) or significant issues (e.g. liquefaction areas, groundwater depths, etc.) that should be considered with the overall PDA-grant funded Development Plan. As noted in the Bay Fair TOD Specific Plan, there are issues with liquefaction and expansive soils on site. Consultant will review available information and will assess the impact on future development and the need for a more detailed analysis based on the development scenario. Findings will be summarized in a memo. C. Flood Zone Review and Localized Hydraulic Model (funded by MTC PSTA Task 2.c) Supported by MTC Priority Sites Technical Assistance funding, the consultant will use the data from the existing FEMA Flood Zone Study to analyze the impact on the development area. • This task will include a review of the prior hydrology study(s) of the drainage channel/creek that are anticipated to be provided by Alameda County Flood Control District that delineates the flows for Estudillo Canal/Creek at the site. Based on the 100- year recurrent flows already developed with the creek, consultant will create a localized hydraulic model that predicts the inundated area and depth of inundation outside of the channel based on the design flow (e.g. a 100-year design flow). An exhibit will be prepared showing the depths of ponding based on cross-sections derived from the aerial topography identified in Task 2.a. • The study will assess the implications of future development, which would remove portions of the Area from the flood plain by raising the surface elevation above the current floodplain elevation and identify necessary mitigation. If unmitigated, filling adjacent to the creek could cause additional inundation upstream and/or downstream of the site. Based on current best practices, it is likely that mitigations may be needed to protect upstream and downstream properties from being impacted by adding capacity within the site (e.g. creating new low-lying areas that would be inundated in lieu of the areas raised out of the flood plain), including the BART station and any inundation effects to those areas. • These mitigations will be identified and will likely require future hydraulic analysis and a CLOMR (Conditional Letter of Map Revision) and LOMR (Letter of Map Revision) with FEMA during final design and after construction. Docusign Envelope ID: 885601F4-01B5-4FAB-A341-08EBC29876AA