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,`APTIM August 1, 2019 Page 2 of 5 and can produce georeferenced HTML's viewable in generic web -browser software programs. SonarWiz also produces digital geographic information for sidescan data that are exportable for incorporation into a GIS database. Nearshore Hardbottom: The nearshore hard bottom edge will be mapped using sidescan sonar between R-19 and R-58. This includes 300 m updrift and 900 m downdrift of the proposed project area (R-20 to R-55). The sidescan sonar survey will also include the area within 250 m offshore of the beach. Pipeline Corridors: The sidescan sonar survey will encompass the area within the pipeline corridor plus the area within 25 m to the left and right of each corridor. Borrow Area: The sidescan sonar survey will encompass the area within 400 m of the proposed borrow area. Task 1 Deliverable A letter report describing equipment and operations, together with sidescan sonar mosaic maps with digitized interpretations, will be produced for this task. In addition, georeferenced GeoTIFF mosaic files, as well as GIS shapefiles will be exported and included as digital appendices to the letter report. Task 1 Schedule The sidescan sonar survey will commence within four (4) weeks of receipt of a Notice to Proceed from the County. It will take approximately one week to mobilize and collect the sidescan sonar data, followed by another two weeks of data processing, interpretation, and deliverable development. Task 1 Cost The lump sum cost for this task is $42,216.50. Task 2: In situ Diver Verification and Assessment of Hardbottom Resources Task 2: Scope of Work The results from the sidescan sonar survey described in Task 2 will guide the in situ diver investigation of hardbottom resources identified in the nearshore, within the pipeline corridors and adjacent to the borrow area. Nearshore Hardbottom: Divers will verify the location and distribution of nearshore hardbottom resources identified from the sidescan sonar survey described in Task 1. If small areas of edge mapping are needed due to data gaps in the sidescan sonar data, divers will use a buoy with a Differential Global Positioning System (DGPS) antenna linked to a topside laptop running HYPACK navigational software to delineate the hardbottom edge. The buoy will be towed by divers along the reef edge to record the position of the divers during the su rvey. FDEP acknowledged in their request for additional information (RAI) #1 (0285993 -009 -JC - dated April 4, 2019) that a sizeable amount of information has been collected on hardbottom resources adjacent to the proposed fill template for the previous Sector 3 Beach Restoration project, and agrees that these data were collected recently enough that they provide information on the status of the natural hardbottom community in this area. Therefore, additional characterization of the nearshore hardbottom area is not proposed.