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,,APTIM Task 5: Scope of Work • Hardbottom Edge Mapping: Mr. James Gray December 8, 2017 Page 6 of 12 APTIM shall map the position of the nearshore hardbottom edge for the entire Sector 5 project area, including 1000 feet north and 2000 feet south of the project area (R-69 to R-88) for a length of approximately 3.6 miles (the hardbottom edge is further offshore beyond 2000 feet south of the project area). A buoy with a Differential Global Positioning System (DGPS) antenna linked to a topside laptop computer running HYPACK navigational software will be towed by divers to record the position of the nearshore hardbottom edge. The divers will follow the inshore contour of the most prominent hardbottom-sand border. The purpose of the survey is to provide a comparison for post -construction edge delineations. • Installing and Monitoring Permanent Transects: Transects will be established at approximately 1000 -foot intervals along the length of the project, including within 1000 feet north and 2000 feet south for up to 23 transects. This includes 20 biological monitoring transects and three (3) sediment only transects. All transects will run perpendicular to the shoreline and extend from the nearshore hardbottom edge to a distance of 150 meters seaward. Stainless steel rods will be used to permanently mark the transects to facilitate repeatability for post -construction monitoring. After transect establishment, a biological survey will be conducted to document the pre -construction condition of the hardbottom using quadrat assessments, sediment measurements and video/photo documentation. Additionally, the PEP Reef located near R-81 to R-83 will be qualitatively assessed during this effort. Up to sixteen (16) 0.75-m2 quadrats will be sampled along each transect to quantify the benthic community. Sediment data will be collected using line -intercept and 1-m interval sediment depth measurements, and video documentation will also be collected for the length of each transect. It is anticipated that the effort to delineate the hardbottom edge, install transects and monitor the transects will take up to 17 field days. Pre -construction data will be compiled and incorporated into an interactive GIS database and in situ data will be entered into an Access database. Data entry, reduction, archiving, and analysis time is included in the cost estimate to address the data management and reporting requirements for those 17 days of field operations. Task 5: Deliverable Raw data will be provided to FDEP and the County within 45 days of completion of the survey. This includes a PDF of the scanned datasheets, excel spreadsheets with quadrat data, interval sediment depth measurements and line -intercept data, shapefiles of the hardbottom edge survey, video and photo documentation. Additionally, APTIM will provide a map of the project area and adjacent hardbottom resources with the hardbottom edge delineation and monitoring transects overlaid onto recent, clear aerial photographs (in digital format). A report is not proposed for the pre -construction monitoring survey. Task 5: Schedule The pre -construction monitoring event will take place during the summer (May — September) prior to project construction. Raw data from field operations will be submitted to the County and FDEP within 45 days of completion of the survey. WO#23: Sector S Permitting and Construction Services Proj. #636232224 104