2021-026 - Laserfiche WebLink

Home Browse Search

APTIM February 5, 2021 Page 2 of 5 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 interface. The purpose of the survey is to provide a baseline for comparison with post - construction hardbottom edge delineations. 2) Installing and Monitoring Permanent Transects: Thirty (38) permanent transects will be established along the length of project influence, which includes 1000 feet north (updrift) and 3000 feet south (downdrift). This includes twenty-four (24) biological monitoring transects and fourteen (14) sediment -only transects. All transects will run perpendicular to the shoreline and extend from the landward hardbottom edge to a distance of 50 meters seaward. Stainless steel rods will be used to permanently mark the transects to facilitate repeatability for post -construction monitoring. Following transect establishment, a biological survey will be conducted to document the pre -construction condition of the hardbottom using the following methods: 1) Quadrat Assessments: Up to nine (9) 0.5-m2 quadrats sampled along each transect to quantify the benthic community. 2) Sediment Measurements: Collected using line -intercept and 1-m interval sediment depth measurements. 3) Video/Photo Documentation: Collected for the length of each transect. It is anticipated that up to 20 days of field operations is required to delineate the hardbottom edge, install permanent transects and monitor the transects. The collected pre -construction data will be compiled and incorporated into an interactive GIS database and the quadrat 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 the field operations. Task 1: Deliverable Raw data will be provided to FDEP and the County including 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/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 the most recent aerial photography (in digital format). A report is not proposed for the pre -construction monitoring survey. APTIM will also provide information or assistance to County staff, as needed or requested. Task 1: 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. Task 1: Cost The lump sum cost for this task is $183,539.43.