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<br />Consulting Services Agreement between City of San Leandro and Last revised 10/09/2022
<br />Terraphase for Tony Lema landfill climate vulnerability assessment Exhibit A – Page 2 of 5
<br />Terraphase will obtain nearby tidal gauge records, precipitation records, and LiDAR topography for use in
<br />the analysis. For each identified scenario, surface water inundation maps will be created using the most
<br />updated LiDAR topographic data for the site. Groundwater surfaces for each scenario will be constructed
<br />based on the best available data for current conditions with the magnitude of SLR superimposed. These
<br />two types of maps will be used together to assess potential future vulnerability to flooding at the site.
<br />Terraphase will also use data from the Coastal Storm Modeling System (CoSMoS) project (USGS 2021),
<br />which has made predictions of storm-induced coastal flooding, erosion, and cliff failures over large
<br />geographic scales.
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<br />An interim technical memorandum will be provided to describe the approach to the SLR assessment,
<br />justification of SLR scenario selections, and results of our analysis.
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<br />Task 2 references:
<br />• California Ocean Protection Council (OPC). 2018. State of California Sea -Level Rise Guidance,
<br />2018 Update.
<br />• Sweet, W.V., B.D. Hamlington, R.E. Kopp, C.P. Weaver, P.L. Barnard, D. Bekaert, W. Brooks, M.
<br />Craghan, G.Dusek, T. Frederikse, G. Garner, A.S. Genz, J.P. Krasting, E. Larour, D. Marcy, J.J.
<br />Marra, J. Obeysekera, M.Osler, M. Pendleton, D. Roman, L. Schmied, W. Veatch, K.D. White, and
<br />C. Zuzak, 2022: Global andRegional Sea Level Rise Scenarios for the United States: Updated
<br />Mean Projections and Extreme Water Level Probabilities Along U.S. Coastlines. NOAA Technical
<br />Report NOS 01. National Oceanic and Atmospheric Administration, National Ocean Service, Silver
<br />Spring, MD, 111 pp.https://oceanservice.noaa.gov/hazards/sealevelrise/noaa -nos-techrpt01-global-
<br />regional-SLR-scenarios-US.pdf
<br />• United States Geological Survey (USGS). 2021. Projecting climate dependent coastal flood risk
<br />with a hybrid statistical dynamical model. DOI 10.1029/2021EF002285.
<br />https://www.usgs.gov/publications/projecting-climate-dependent-coastal-flood-risk-hybrid-
<br />statistical-dynamical-model
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<br />Task 3: Preparation of Long-Term Flood Protection and Adaptation Plan
<br />Task 3 will include preparing the Long-Term Flood Protection and Adaptation Plan (Plan) based on
<br />previously completed Site background review, flood research, and flood quantification/justification tasks.
<br />Preparation of the Long-Term Flood Protection Plan will include developing a draft version for review by the
<br />City of San Leandro, revisions, and completion of a final version that ad dresses City comments.
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<br />Task 3A: Vulnerability Assessment
<br />The vulnerability assessment section of the Plan will identify existing features that may be vulnerable to
<br />future flooding extents. Items to be considered include, among others, long -term cap stability, infiltration of
<br />water into the landfill waste mass, increase in leachate amounts, leachate and landfill gas migration to
<br />other aquifers or surface waters, subsidence, erosion, stability of saturated landfill waste mass, and
<br />qualitative structural stability of buildings constructed on top of the landfill.
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<br />Task 3B: Adaptation Plan
<br />The adaptation plan section of the Plan will identify strategies and potential Site improvements which can
<br />be implemented over various time periods to improve resilience of the landfill in response to future flooding
<br />extents. The adaptation plan will include conceptual descriptions of strategies which may include berms,
<br />groundwater containment areas, ponds, subsurface conduits, golf course irrigation/maintenance practices,
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