Volume 5 - Appendices Appendix 14 -Flora and Vegetation Assessment
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PROJECT SEA DRAGON STAGE 1 LEGUNE GROW-OUT FACILITY DRAFT ENVIRONMENTAL IMPACT STATEMENT VOLUME 5 - APPENDICES APPENDIX 14 -FLORA AND VEGETATION ASSESSMENT Volume 5 - Appendices Appendix 14 -Flora and Vegetation Assessment 1 CO2 Australia & Seafarms Group Ltd Project Sea Dragon Stage 1 Grow-out Facility EIS Terrestrial flora report August 2016 Prepared by: Astrebla Ecological Services This Project Sea Dragon Stage 1 Grow-out Facility EIS Terrestrial Flora Report (‘the Repor’) has been prepared by Astrebla Ecological Services (‘’) on behalf of and for CO2 Australia Ltd (‘’) in accordance with an agreement between AES and CO2. The Report may only be used and relied on by CO2 for the purpose of informing environmental assessments and planning approvals for the proposed Project Sea Dragon (Purpose) and may not be used by, or relied on by any person other than CO2. The services undertaken by AES in connection with preparing the Report were limited to those specifically detailed in the Report. The Report is based on conditions encountered and information reviewed, including assumptions made by AES, at the time of preparing the Report. Assumptions made by AES are those stated throughout the Report. To the maximum extent permitted by law AES expressly disclaims responsibility for or liability arising from: •any error in, or omission in connection with assumptions, or •reliance on the Report by a third party, or use of this Report other than for the Purpose. CO2 Australia Executive Summary Seafarms Group Limited is proposing to develop Project Sea Dragon, a large fully integrated aquaculture project that will develop reliable, long-term and large scale production of black tiger prawns (Penaeus monodon). The main operations will be at the Grow-Out Facility (GOF) located on Legune Station, approximately 105 km north-east of Kununurra on the western border of the Northern Territory. This Terrestrial Flora Report is provided as part of an overall Environmental Impact Assessment (EIS) for the development of Stage 1 of the GOF, and reports on the findings of a desktop and field investigation into the terrestrial flora of the project area. The grow-out centre is the main part of the GOF area, and is proposed on an estuarine-deltaic plain (the Legune delta) of black cracking clay comprising the largest of its type in the NT, located between the estuaries of the Keep and Victoria Rivers. The vegetation on the Legune delta is characterised primarily by a mosaic of grasslands dominated by northern rice grass and canegrass, interspersed with ephemeral or seasonal wetland formed on playas and smaller areas of gilgai. To the south of the GOF, where service corridors are proposed, large areas of closed sedgeland and grassland fringe permanent wetland associated with Alligator Creek, interspersed with extensive grassland. The estuarine-deltaic plain is bordered to the north, east and west by a particularly extensive coastal plain, the second largest in northern Australia and the NT, comprised of a plain of mostly bare marine sediment patchily vegetated with samphire forbland and dissected by estuarine creeks fringed by low closed mangrove forest. A low coastal erosional plain is located to the south west of the GOF, over which the access road to Kununurra is located. This coastal erosional plain is characterised by Darwin stringybark and Darwin woollybutt woodland growing on sandy soils. Two near threatened species were recorded – but both do not occur within the project footprint and impacts are not expected to these species. In addition, three species listed as data deficient were detected within the project footprint - as populations of these species are likely to be present within the clearing footprint, pre-clearance population surveys are recommended in the habitats in which they occur. No species of conservation significance was detected from the GOF. A total of 20 vegetation communities were defined and mapped as a result of the field survey. Of these, two are considered likely to be partially groundwater dependent - Melaleuca open forest fringing Forsyth Creek, and elements of the M. dealbata woodland community on the Forsyth Creek floodplain and where it fringes the coastal erosional plain. However, this dependence is thought likely to be facultative. Eight species of declared weed were recorded, with the most common being hyptis (Hyptis suaveolens*) and spinyhead sida (Sida acuta*). Impacts to vegetation from this project are expected to be restricted to those experienced from clearing. In general, clearing impacts to vegetation communities in the project area will be moderate to negligible at the local scale, and minor to negligible at the bioregional and NT-wide scale. Potential land degradation impacts can be managed with appropriate planning and the implementation of soil conservation plans and sediment and erosion management measures. Impacts to fauna habitat associated with clearing and possible impacts to estuarine ecology from eutrophication as a result of wastewater disposal have been covered elsewhere in the EIS. Astrebla Ecological Services| Flora report for Project Sea Dragon Stage 1 Grow-out Facility EIS|CO2 Australia/Seafarms Group Ltd i CO2 Australia Contents Executive Summary ............................................................................................................................ i Abbreviations................................................................................................................................... vi Glossary ........................................................................................................................................... vi 1 Introduction .............................................................................................................................. 1 1.1 Project overview ................................................................................................................ 1 1.2 Terminology....................................................................................................................... 1 1.2.1 Project footprint......................................................................................................... 1 1.2.2 Project area................................................................................................................ 2 1.2.3 Study area .................................................................................................................. 2 1.3 Scope of this report............................................................................................................ 2 2 Legislative review in relation to vegetation................................................................................ 5 2.1 Northern Territory legislation............................................................................................. 5 2.1.1 Territory Parks and Wildlife Conservation Act 2000 .................................................... 5 2.1.2 Weeds Management Act 2001.................................................................................... 5 2.1.3 Land clearing .............................................................................................................. 5 2.2 Commonwealth legislation................................................................................................. 7 2.2.1 The Environment Protection and Biodiversity Conservation Act 1999 ......................... 7 3 Methods.................................................................................................................................... 8 3.1 Introduction....................................................................................................................... 8 3.2 Desktop survey .................................................................................................................. 8 3.3 Field survey........................................................................................................................ 9 3.4 Vegetation community mapping ...................................................................................... 10 4 Survey results .......................................................................................................................... 11 4.1 Location ........................................................................................................................... 11 4.2 Protected areas and sites of conservation significance ..................................................... 11 4.3 Climate ............................................................................................................................ 11 4.4 Landscape description...................................................................................................... 12 4.4.1 Geology.................................................................................................................... 12 4.4.2 Geomorphology and hydrology ................................................................................ 13 4.5 Threatened species and communities .............................................................................. 23 4.5.1 Commonwealth EPBC Act......................................................................................... 23 4.5.2 Northern Territory TWPC Act.................................................................................... 24 4.6 Vegetation communities .................................................................................................. 29 Astrebla