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A APTIM Task 7: Geotechnical Evaluation and Compatibility Analysis Task 7: Scope of Work March 14, 2018 Page 8 of 10 APTIM will develop a study to investigate potential fill sources to determine their compatibility with the native sand of Sector 3. Sand sources, both offshore and upland, will be preliminarily evaluated to be utilized for fill material. Sediment characteristics that will be analyzed include grain size distribution, carbonate content, and color. Native sand of Sector 3 will be represented by geotechnical data obtained from previous studies in the County. It is assumed that no additional sampling will be required; thus, this proposal does not include native beach sampling as part of the scope. A composite grain size curve of the Sector 3 native sand will be developed to compare to potential fill sources. Offshore sand sources will be preliminarily designed and evaluated by utilizing existing data from previous offshore sand source investigations (ATM, 2001), including core logs and granularmetric data. The offshore evaluation will focus on the South Borrow Area, as it has been previously permitted and successfully used in the County. If additional field work of the offshore borrow area is required by FDEP, then the associated field work, analysis, design, and coordination will be conducted under a separate work order. Offshore areas will be evaluated in terms of available sand, proximity to the Sector 3 shoreline, and compatibility with the Sector 3 native beach sand in terms of grain size distribution, carbonate content, and color. If sufficient data exists, composite grain size curves and statistics will be developed to represent offshore borrow areas. These curves and composite statistics will be used to evaluate the compatibility with the native sand of Sector 3. Evaluation of upland sand sources will include those previously utilized for construction on the County's beaches, have geotechnical data of recent representative samples of the proposed fill material, actively produce sand (or can easily reestablish producing sand), have sufficient quantities available, have sufficient stockpiling area, provide operational information, and are compatible with the Sector 3 native beach sand in terms of grain size distribution, carbonate content, and color. If sufficient data exists, composite grain size curves will be developed to represent potential upland sources. These curves and composite statistics will be used to evaluate the compatibility with the native sand of Sector 3. Recommendations will be provided to move forward with upland and/or offshore sand sources as fill material for the Sector 3 project. If required, steps will be identified to further investigate possible upland or offshore sources. Task 7: Deliverable A summary of the work described above will be included as an Appendix in the Feasibility Report (Task 1), unless the offshore bathymetric survey collection (Task 8) dictates this to be submitted later under separate cover. Task 7: Schedule APTIM will provide the deliverable with the Feasibility Report (Task 1). Task 7: Cost The lump sum cost for this task is $22,752.00. Sector 3 — 2018006 — WO#2: Design and Permitting Proj. #631235714