APP a Marine Ecology Study.Pdf
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Proposed Construction, Operation and Decommissioning of the Marine Outfall Pipeline and Associated Infrastructure for Frontier Saldanha Utilities (Pty) Ltd in the Saldanha Bay Region, Western Cape Marine Ecology Specialist Study Prepared for: Prepared by: PISCES Environmental Services (Pty) Ltd September 2014 PISCES Envir onmental Services (Pt y) Lt d Contact Details: Andrea Pulfrich, Pisces Environmental Services PO Box 31228, Tokai 7966, South Africa, E-mail: [email protected] Environmental Impact Assessment (EIA) for the proposed construction, operation and decommissioning of the Saldanha Regional Marine Outfall project of Frontier Saldanha Utilities (Pty) Ltd. at Danger Bay in the Saldanha Bay region EXPERTISE AND DECLARATION OF INDEPENDENCE This report was prepared by Dr Andrea Pulfrich of Pisces Environmental Services (Pty) Ltd. Established in 1998, Pisces has aquired considerable experience in undertaking specialist environmental impact assessments, baseline and monitoring studies, and Environmental Management Programmes relating to marine diamond mining and dredging, hydrocarbon exploration, harbour expansions and thermal/hypersaline effluents. Andrea has a BSc (Hons) and MSc degree in Zoology from the University of Cape Town and a PhD in Fisheries Biology from the Institute for Marine Science at the Christian-Albrechts University, Kiel, Germany. She is a registered Environmental Assessment Practitioner and member of the South African Council for Natural Scientific Professions, South African Institute of Ecologists and Environmental Scientists, and International Association of Impact Assessment (South Africa). This specialist report was compiled as a desktop study on behalf of the CSIR, Stellenbosch for their use in preparing an Environmental Impact Assessment Report and developing an Environmental Management Plan for the proposed construction, operation and decommissioning of the marine outfall pipeline and associated infrastructure for Frontier Saldanha Utilities (Pty) Ltd in the Saldanha Bay Region, Western Cape. The compilation followed a review process of published (peer reviewed) and unpublished literature and the assessment of potential impacts based on proposed activities and identification of impacts (and their mitigation) within the available literature. I do hereby declare that Pisces Environmental Services (Pty) Ltd is financially and otherwise independent of the Applicants and CSIR. Dr Andrea Pulfrich VOLUME II, Appendix A – Marine Ecology Study i Environmental Impact Assessment (EIA) for the proposed construction, operation and decommissioning of the Saldanha Regional Marine Outfall project of Frontier Saldanha Utilities (Pty) Ltd. at Danger Bay in the Saldanha Bay region TABLE OF CONTENTS ABBREVIATIONS, UNITS AND GLOSSARY ....................................................................................... IV EXECUTIVE SUMMARY ........................................................................................................................ XI 1 INTRODUCTION .............................................................................................................................. 1 1.1 Scope of Work ......................................................................................................................... 2 1.2 Approach to the Study ............................................................................................................. 2 1.3 Limitations and Assumptions ................................................................................................... 3 1.4 Structure of the Report ............................................................................................................ 4 1.5 Legal and Permitting Requirements ........................................................................................ 4 2 PROJECT DESCRIPTION ............................................................................................................. 12 2.1 The REE Separation Plant .................................................................................................... 12 2.2 The Chlorine, Caustic Soda and Hydrochloric Acid Facility .................................................. 13 2.3 The Waste Water Treatment Facility ..................................................................................... 14 2.4 The Desalination Plant .......................................................................................................... 15 2.5 Saldanha Regional Marine Outfall ......................................................................................... 16 3 IDENTIFICATION OF KEY ISSUES AND SOURCES OF POTENTIAL ENVIRONMENTAL IMPACT .......................................................................................................................................... 20 3.2 Identification of Key Issues .................................................................................................... 20 3.2.1 Construction Phase .............................................................................................. 20 3.2.2 Operational Phase ................................................................................................ 20 3.2.4 Decommissioning Phase ...................................................................................... 21 3.3 Assessment Methodology ..................................................................................................... 22 4 DESCRIPTION OF THE AFFECTED ENVIRONMENT ................................................................. 25 4.1 Geographical Setting ............................................................................................................. 25 4.2 Physical Environment ............................................................................................................ 26 4.2.1 Winds, Currents and Circulation Patterns ............................................................ 26 4.2.2 Waves and Tides .................................................................................................. 27 4.2.3 Upwelling and Plankton Production ..................................................................... 28 4.2.4 Organic Inputs ...................................................................................................... 29 4.2.5 Low Oxygen Events ............................................................................................. 30 4.2.6 Turbidity ................................................................................................................ 31 4.3 Biological Environment .......................................................................................................... 32 4.3.1 Sandy Substrate Habitats and Biota .................................................................... 32 4.3.2 Rocky Substrate Habitats and Biota .................................................................... 34 4.3.3 The Water Body ................................................................................................... 40 4.3.4 Beneficial Uses ..................................................................................................... 44 5 MODELLED CHANGES IN THE MARINE ENVIRONMENT DUE TO DISCHARGES OF EFFLUENTS TO THE MARINE ENVIRONMENT ......................................................................... 49 5.1 Scenarios Modelled ............................................................................................................... 49 5.2 Model Results ........................................................................................................................ 50 6 ASSESSMENT OF ENVIRONMENTAL IMPACTS ....................................................................... 57 6.1 Assessment of Potential Environmental Impacts .................................................................. 57 6.1.1 Construction of Discharge Pipeline ...................................................................... 57 6.1.2 Operational Phase ................................................................................................ 68 6.1.3 Decommisioning Phase ...................................................................................... 121 6.2 Project Impacts and Environment Interaction Points .......................................................... 121 6.3 Cumulative Impacts ............................................................................................................. 121 VOLUME II, Appendix A – Marine Ecology Study ii Environmental Impact Assessment (EIA) for the proposed construction, operation and decommissioning of the Saldanha Regional Marine Outfall project of Frontier Saldanha Utilities (Pty) Ltd. at Danger Bay in the Saldanha Bay region 7 RECOMMENDATIONS AND CONCLUSIONS ............................................................................ 122 7.1 Environmental Acceptability and Comparison of Alternatives ............................................. 122 7.2 Mitigation Measures ............................................................................................................ 123 7.3 Monitoring Recommendations ............................................................................................. 125 7.4 Conclusions ......................................................................................................................... 127 8 REFERENCES ............................................................................................................................. 131 A.1 Potential Effects