APPENDIX 12 ARROW LNG PLANT Marine and Estuarine Ecology Impact Assessment MARINE AND ESTUARINE ECOLOGY IMPACT ASSESSMENT Arrow LNG Plant MARINE AND ESTUARINE ECOLOGY IMPACT ASSESSMENT Arrow LNG Plant October 2011 CR 7033_09_v6 Coffey Environments Australia Pty Ltd ABN 65140765902 (formerly Coffey Natural Systems) Level 2, 12 Creek Street Brisbane QLD 4000 Australia T (+61) (7) 3002 0400 F (+61) (7) 3002 0444 coffey.com Marine and Estuarine Ecology Impact Assessment Arrow LNG Plant © Coffey Environments Pty Ltd October 2011 Project director David Gwyther Project manager Chelsea Kavanagh Version: Details: Approved: Date: CR 7033_09_v1 Initial draft to client RL May 2011 CR 7033_09_v2 Second draft to client RL August 2011 CR 7033_09_v3 Third draft to client EW September 2011 CR 7033_09_v4 Forth draft to client EW September 2011 CR 7033_09_v5 Fifth to client EW September 2011 CR 7033_09_v6 Final to client EW October 2011 Coffey Environments 7033_marine_and_estuarine_ecology_impact_assessment_v6.doc i Marine and Estuarine Ecology Impact Assessment Arrow LNG Plant CONTENTS EXECUTIVE SUMMARY VI 1. INTRODUCTION 1 1.1 Purpose and Scope 1 2. PROJECT DESCRIPTION 3 2.1 Proponent 3 2.2 Arrow LNG Plant 3 2.2.1 LNG Plant 3 2.2.2 Feed Gas Pipeline 7 2.2.3 Dredging 8 2.2.4 Decommissioning 9 3. LEGISLATIVE CONTEXT 11 3.1 Commonwealth Legislation 11 3.2 State Legislation 12 3.3 Policies and Subordinate Legislation 15 3.4 Internationally Protected Areas 15 4. STUDY METHOD 17 4.1 Approach to Existing Marine and Estuarine Environment 17 4.2 Approach to Impact Assessment 20 4.2.1 Identifying Impacts 21 4.2.2 Significance 22 5. EXISTING ENVIRONMENTAL VALUES 27 5.1 Introduction 27 5.2 Physical Environment 28 5.2.1 Benthic zone 28 5.2.2 Reef and Rock Substrate 30 5.2.3 Intertidal Mudflats 32 5.3 Flora 32 5.3.1 Saltmarsh 32 5.3.2 Mangroves 33 5.3.3 Seagrass 37 5.4 Fauna 39 5.4.1 Dugongs 39 5.4.2 Turtles 44 5.4.3 Cetaceans 48 5.4.4 Saltwater Crocodiles 50 5.4.5 Fish and Shellfish 51 5.4.6 Sea Snakes 56 5.4.7 Seahorses and Pipefish 57 Coffey Environments 7033_marine_and_estuarine_ecology_impact_assessment_v6.doc ii Marine and Estuarine Ecology Impact Assessment Arrow LNG Plant 5.4.8 Macrobenthic Communities 59 5.4.9 Plankton 60 5.4.10 Introduced Species and Pest Species 60 6. ISSUES AND POTENTIAL IMPACTS 63 6.1 Loss and Disturbance of Marine and Estuarine Habitat 63 6.1.1 Direct Construction Impacts 63 6.1.2 Indirect impacts 69 6.2 Impact on Marine and Estuarine Fauna and Flora 75 6.2.1 Boat Strike 75 6.2.2 Underwater Noise 78 6.2.3 Lighting 87 6.2.4 Sedimentation from Propwash 88 6.3 Loss of Commercial and Recreational Fishing Access 88 6.4 Introduced Species and Pest Species 89 6.5 Shipping Activities and Accidents 90 7. AVOIDANCE, MITIGATION AND MANAGEMENT MEASURES 93 7.1 Loss and Disturbance of Marine and Estuarine Habitat 93 7.1.1 Construction 93 7.1.2 Operations 95 7.2 Impact on Marine and Estuarine Fauna 95 7.2.1 Boat Strike 95 7.2.2 Underwater Noise 96 7.2.3 Lighting 96 7.2.4 Dredging 97 7.3 Reduction of Commercial and Recreational Fishing Access 97 7.4 Introduced Species and Pest Species 97 7.5 Shipping Activities and Accidents 98 8. ASSESSMENT OF RESIDUAL EFFECTS 101 8.1 Loss and Disturbance of Marine and Estuarine Habitat 101 8.1.1 Construction 101 8.1.2 Operations 101 8.2 Impacts to Marine and Estuarine Fauna 101 8.2.1 Boat Strike 101 8.2.2 Underwater Noise 101 8.2.3 Lighting 102 8.3 Loss of Commercial and Recreational Fishing Access 102 8.4 Introduced Species and Pest Species 103 8.5 Shipping Accidents and Activities 103 9. CUMULATIVE IMPACT 105 9.1 Loss and Disturbance of Marine and Estuarine Habitat 105 9.2 Impacts to Marine and Estuarine Fauna 108 9.2.1 Boat Strike 108 9.2.2 Underwater Noise 110 9.2.3 Lighting 110 Coffey Environments 7033_marine_and_estuarine_ecology_impact_assessment_v6.doc iii Marine and Estuarine Ecology Impact Assessment Arrow LNG Plant 9.3 Loss of Commercial and Recreational Fishing Access 110 9.4 Introduction of Invasive Species, Shipping Activities and Accidents 111 10. INSPECTION AND MONITORING 113 11. CONCLUSIONS 115 12. REFERENCES 123 13. ACRONYMS AND GLOSSARY 133 Figures 1 Site Locality 18 2 Field investigation study area 19 3 Marine and estuarine habitat distribution in the Port Curtis region 29 4 Reef and macrobenthic distribution in the Port Curtis region 31 5 Port of Gladstone - Rodds Bay Dugong Protection Area and seagrass beds in the Port Curtis Region 41 6 Monitored seagrass beds in the Fishermans Landing area 42 7 Monitored seagrass beds in Rodds Bay 43 8 Turtle nesting sites in the Gladstone region 46 9 Commercial catch for all species and fishery types in Central Queensland waters, 2005 54 10 Commercial catch quantity and gross value of production in grid S30, 1988-2010 55 11 Marine habitat impact areas 65 12 Curtis Island potential marine habitat impact areas 66 13 Marine habitat impact areas tunnel entry shaft and tunnel spoil disposal area 68 14 Marine habitat impact areas Launch Site 4N 70 15 Marine habitat impact areas Launch Site 1 and Calliope River dredging. 71 16 Potential marine habitat indirect impact areas near Curtis Island 72 17 Potential marine habitat indirect impact areas in Calliope River 73 18 Underwater noise projection at Hamilton Point 86 Tables 1 Sensitivity of the Environmental Value 23 2 Magnitude of the Impact 24 3 Matrix of Significance of Impact 24 4 Conservation Status of Marine Turtles in Queensland Waters 44 5 Conservation Status of Whales and Dolphins (Cetaceans) in Queensland Waters 48 6 Conservation Status of Marine Sea Snakes in Queensland Waters 56 7 Conservation Status of Marine Seahorse and Pipefish in Queensland Waters 57 8 Estimated Schedule of Disturbance on Habitat Types for the Arrow LNG Plant 64 9 Estimated Type, Number and Frequency of Marine Vessels for the Arrow LNG Plant 76 10 Pile Driving Noise Levels during Various Projects 80 Coffey Environments 7033_marine_and_estuarine_ecology_impact_assessment_v6.doc iv Marine and Estuarine Ecology Impact Assessment Arrow LNG Plant 11 Avoidance and Injury Noise Levels for Turtles, Dugongs and Cetaceans 81 12 Significance and Magnitude of Underwater Noise on Environmental Values in the Port Curtis Region 87 13 Seasonal Reproductive Periods for Marine Turtles in the Port Curtis Region 87 14 Shipping and Pollution Incidents in the Great Barrier Reef World Heritage Area for 2000 to 2004* 90 15 Magnitude of Shipping Activities and Accidents on Environmental Values in the Port Curtis Region 91 16 Residual Significance of Underwater Noise on Environmental Values in the Port Curtis Region 102 17 Significance of Shipping Activities and Accidents on Environmental Values in the Port Curtis Region 103 18 Estimated Cumulative Direct and Indirect Impact on Environmental Values 107 19 Estimated Cumulative Frequency of Marine Vessels 109 20 Inspection and monitoring for impacted environmental values 114 21 Significance Impacts on Environmental Values for the Arrow LNG Plant 117 Plates 1 Example of Rock Substrate at Hamilton Point 35 2 Example of Salt Couch and Bead Weed along the Calliope River 35 3 Example of Rhizophora along the Calliope River 36 4 Example of Avicennia at Hamilton Point 36 Attachments Attachment A Terms of Reference Cross Reference Table Appendices Appendix A Arrow Energy LNG Plant Estuarine and Marine Ecology Field Investigations 2010-2011 (Phase I & II) Coffey Environments 7033_marine_and_estuarine_ecology_impact_assessment_v6.doc v Marine and Estuarine Ecology Impact Assessment Arrow LNG Plant EXECUTIVE SUMMARY Arrow CSG (Australia) Pty Ltd (Arrow Energy) is investigating the development of a liquefied natural gas (LNG) plant on Curtis Island. This technical study assesses the impacts of the project and project infrastructure on the marine and estuarine environment of Port Curtis. This impact assessment has been prepared through desktop and field studies of the study area. Port Curtis forms a narrow coastal embayment of approximately 200 km2 that separates Curtis Island from the mainland. The marine and estuarine environment of Port Curtis is characterised by a large tidal range of greater than 4 m and consequentially has high tidal currents and extensive intertidal areas, and is also influenced by freshwater inflow from a number of rivers and creeks, particularly the Calliope River and Boyne River. Port Curtis has naturally high levels of turbidity and suspended sediments. The high tidal range results in a typical pattern of intertidal and coastal zonation from: • Saltmarsh and mud flat areas that are inundated only during extreme spring tides. • Intertidal mudflats and mangroves that dominate estuarine areas of Targinie Creek, The Narrows and North China Bay on the eastern shore of Port Curtis. • Subtidal mudflats and tidal channels. • Seagrass beds extending from intertidal to subtidal areas. • Rock and reef habitats extending intertidally and subtidally from the rocky headlands, predominantly on Curtis Island on the eastern shore of Port Curtis. Areas in and around Port Curtis also provide important habitats used by a diverse range of species, including the dugong (Dugong dugon), six of the world’s seven species of protected marine turtles, cetaceans (including the potentially endemic Australian snubfin dolphin (Orcaella heinsohni) and Indo-Pacific humpback dolphin (Sousa chinensis)), the saltwater crocodile (Crocodylus porosus), and a range of fish, nekton, sea snakes, seahorses and pipefish (syngnathid fishes), macrobenthic and plankton species. The likelihood of occurrence of some of these, especially the estuarine crocodile, is low. As one of Australia’s largest ports, Port Curtis serves numerous large and expanding industries.