Appendix I Sediment Spillage APPENDIX I EVALUATION OF EXPECTED SEDIMENTATION EXPOSURE IN THE OFFSHORE OF PORT EVERGLADES AS A RESULT OF THE PORT EVERGLADES PROJECT PORT EVERGLADES, FLORIDA PROJECT Port Everglades, Florida Project December 2020 I‐i Appendix I Sediment Spillage This page intentionally left blank Port Everglades, Florida Project December 2020 I‐ii Appendix I Sediment Spillage Table of Contents I INTRODUCTION ‐ EVALUATION OF EXPECTED SEDIMENTATION EXPOSURE IN THE OFFSHORE OF PORT EVERGLADES AS A RESULT OF THE PORT EVERGLADES PROJECT I‐1 I.1 Dredge Plume Development ................................................................................... I‐1 I.2 Sediment Quantities and Characteristics ................................................................ I‐3 I.3 Dredge Equipment .................................................................................................. I‐7 I.4 Spillage Estimates ................................................................................................... I‐7 I.5 Sediment Deposition Distribution ........................................................................... I‐9 I.5.1 Exponential Distributions and Dilution for CSD and Overflow .................... I‐9 I.5.2 Representative Currents Fields and Distributions .................................... I‐10 I.5.3 Release Depths and Settling Distances ..................................................... I‐12 I.5.4 Exponential Distributions and Dilution for Mechanical Dredging ............. I‐14 I.6 Sediment Thickness Exposure ............................................................................... I‐14 I.6.1 Scenario 1 ................................................................................................ I‐15 I.6.2 Scenario 2 ................................................................................................ I‐20 I.6.3 Scenario 3 ................................................................................................ I‐25 I.6.4 Scenario 4 ................................................................................................ I‐29 I.6.5 Direct Impacts .......................................................................................... I‐34 I.7 Summary .............................................................................................................. I‐34 I.8 References ............................................................................................................ I‐38 I.9 Addendum 1 ‐ Evaluation of Expected Sedimentation Exposure Offshore of Port Everglades as a Result of the Port Everglades Deepening Project .................. I‐40 I.9.1 Introduction ............................................................................................. I‐40 I.9.2 Sediment Quantities and Characteristics ................................................. I‐40 I.9.3 Dredge Equipment ................................................................................... I‐43 I.9.4 Spillage Estimates .................................................................................... I‐43 I.9.5 Sediment Deposition Distribution ............................................................ I‐44 I.9.6 Summary ................................................................................................. I‐62 I.9.7 References ............................................................................................... I‐63 I.10 Addendum 2 – Distance Tables with Statistics ...................................................... I‐65 List of Tables Table I‐1. Summary of sediment quantities, percent fines, and total quantities of fines. ................. I‐6 Table I‐2. Summary of dredge spill information. ................................................................................ I‐9 Table I‐3. Distance clay particles may travels before reaching a depth of 15 m for various release depths, fall velocities and current speeds. ................................................................. I‐13 Port Everglades, Florida Project December 2020 I‐iii Appendix I Sediment Spillage Table I‐4. Distance north and south of the channel of sedimentation thickness under scenario 1: a CSD with overflow of various quantities at various overflow release depths for segments 1 (A), 2 (B), and 3 (C). ................................................................................. I‐16 Table I‐5. Estimates of Exposure acreage for each benthos category for a given pre‐defined value of sedimentation exposure for SCENARIO 1: a CSD with overflow at 3.0 m water depth. ......................................................................................................................... I‐19 Table I‐6. Distance north and south of the channel of sedimentation thickness under scenario 2: a CSD with barge decanting at 3.0 m water depth for segments 1 (A), 2 (B), and 3 (C).I‐21 Table I‐7. Estimates of Exposure acreage for each benthos category for a given pre‐defined value of sedimentation exposure for Scenario 2: a CSD with barge decanting at 3.0 m water depth. ............................................................................................................... I‐24 Table I‐8. Distance north and south of the channel of sedimentation thickness under scenario 3: a CSD with direct pump to offshore disposal for segments 1 (A), 2 (B), and 3 (C)..... I‐26 Table I‐9. Estimates of Exposure acreage for each benthos category for a given pre‐defined values of sedimentation exposure for Scenario 3: a CSD with direct pump to offshore disposal. ...................................................................................................................... I‐28 Table I‐10. Distance north and south of the channel of sedimentation thickness under scenario 4: mechanical dredge with barge decant for segments 1 (A), 2 (B), and 3 (C)............... I‐30 Table I‐11. Estimates of Exposure acreage for each benthos category for a given pre‐defined value of sedimentation exposure for Scenario 4: mechanical dredge with barge decant. I‐33 Table I‐12. Direct Impacts in the Navigation Channel (not including side slope impacts). .............. I‐34 Table I‐13. Summary of assumptions. ............................................................................................... I‐35 Table I‐14. Summary of scenarios and spill volumes. ....................................................................... I‐37 Table I‐15. Summary of sediment quantities, percent coarse, and total quantities of coarse material. ..................................................................................................................... I‐42 Table I‐16. Summary of Dredge Spill Information. ........................................................................... I‐44 Table I‐17. Distance sand particles may travel before reaching a depth of 15 m for various release depths, fall velocities and current speeds. ................................................................. I‐47 Table I‐18. Summary of assumptions. ............................................................................................... I‐48 Table I‐19. Distance north and south of the channel of sedimentation thickness under scenario 1: a CSD with overflow of various quantities at various overflow release depths for segments 1 (A), 2 (B), and 3 (C). ................................................................................. I‐51 Table I‐20. Estimates of Exposure acreage for each benthos category for a given pre‐defined value of sedimentation exposure for SCENARIO 1: a CSD with overflow at 3.0 m water depth. ......................................................................................................................... I‐53 Table I‐21. Distance north and south of the channel of sedimentation thickness under scenario 2: a CSD with spill at the cutterhead for segments 1 (A), 2 (B), and 3 (C)...................... I‐54 Table I‐22. Estimates of Exposure acreage for each benthos category for a given pre‐defined value of sedimentation exposure for Scenario 2: a CSD with spill at the cutterhead. ........ I‐57 Table I‐23. Distance north and south of the channel of sedimentation thickness under scenario 4: mechanical dredge with barge decant for segments 1 (A), 2 (B), and 3 (C)............... I‐58 Table I‐24. Estimates of Exposure acreage for each benthos category for a given pre‐defined value of sedimentation exposure for Scenario 4: mechanical dredge. ............................... I‐61 Table I‐25. Summary of scenarios and spill volumes for coarse sediment. ...................................... I‐62 Table I‐26. Distance north and south of the channel of sedimentation thickness under scenario 1: a CSD with overflow at a release depth of 3.0 m for segments 1 (A), 2 (B), and 3 (C) for fines (d50 < 0.062 mm). ......................................................................................... I‐65 Port Everglades, Florida Project December 2020 I‐iv Appendix I Sediment Spillage Table I‐27. Distance north and south of the channel of sedimentation thickness under scenario 2: a CSD with barge decanting at 3.0 m water depth for segments 1 (A), 2 (B), and 3 (C) for fines (d50 < 0.062 mm). .................................................................................... I‐66 Table I‐28. Distance north and south of the channel of sedimentation thickness under scenario 3: a CSD with direct pump to offshore disposal for segments 1 (a), 2 (b), and 3 (c) for fines (d50 < 0.062 mm). ..............................................................................................