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Environmental Impact Report Operation of 1 MW Geothermal Power Plant at Innamincka Geodynamics Limited June 2014 Contents 1.0 Introduction ......................................................................................................... 5 2.0 Current Approvals .............................................................................................. 6 3.0 Proposed Activity and Location ........................................................................ 7 4.0 Operational Changes Since 2008 .................................................................... 13 4.1 Management System Changes ..................................................................................... 13 4.2 Operational Changes ..................................................................................................... 13 4.3 Geothermal Power Generation Process ........................................................................ 13 4.4 Geofluid Management.................................................................................................... 14 4.5 Site Offices, Power Plant and Facilities ......................................................................... 15 4.6 Power Plant Environmental Safeguards and Controls .................................................. 15 4.7 Wastewater Management .............................................................................................. 16 4.8 Power Generation and Energy Supply .......................................................................... 16 4.9 Fuel and Chemical Storage ........................................................................................... 16 4.10 Water Supply ................................................................................................................. 16 4.11 Solid Waste Management .............................................................................................. 17 4.12 Workforce and Accommodation ..................................................................................... 17 4.13 Decommissioning and Rehabilitation ............................................................................. 17 5.0 Stakeholder Consultation ................................................................................ 19 6.0 Description of Environment and New Information ........................................ 20 6.1 Surrounding Land Use ................................................................................................... 20 6.2 Climate ........................................................................................................................... 22 6.3 Land Systems ................................................................................................................ 22 6.4 Surface Water ................................................................................................................ 22 6.5 Groundwater and Soils .................................................................................................. 23 6.6 Native Vegetation ........................................................................................................... 26 6.7 Fauna ............................................................................................................................. 30 6.8 Heritage ......................................................................................................................... 34 6.9 Noise and Air Quality ..................................................................................................... 34 6.10 Pest Plants and Feral Animals ....................................................................................... 35 Page 3 of 66 6.11 Socio-economic Issues ...................................................................................................... 35 7.0 Environmental Risk Assessment and Mitigation Measures ......................... 36 7.1 Risk Assessment Process ............................................................................................. 36 7.1.1 Definition of Consequences ................................................................................... 36 7.1.2 Definition of Likelihood ........................................................................................... 37 7.1.3 Risk Ranking ................................................................................................................. 37 7.2 Environmental Aspects & Mitigation Measures ............................................................. 38 7.2.1 Erosion .......................................................................................................................... 38 7.2.2 Weeds and pests .......................................................................................................... 39 7.2.3 Dust ............................................................................................................................... 39 7.2.4 Groundwater and Geofluid ............................................................................................ 40 7.2.5 Native Fauna ................................................................................................................. 41 7.2.6 Indigenous Heritage ...................................................................................................... 41 7.2.7 Fuels, Chemicals and Wastewater Treatment .............................................................. 42 7.2.8 Solid Waste Management ............................................................................................. 43 7.2.9 Decommissioning and Site rehabilitation ...................................................................... 43 7.2.10 Other Aspects ............................................................................................................. 44 8.0 References ........................................................................................................ 45 Appendix A – Goal Attainment Scaling Criteria ................................................... 46 Appendix B1 – Exposure Monitoring - H4 Cleanup Flow .................................... 48 Appendix B2 - Habanero 4 Open Flow Test – Surface Soil Assessment ........... 49 Appendix C – Habanero Site Heritage Report ...................................................... 50 Appendix D – Alien Species Flora Assessment ................................................... 51 Appendix E – Risk Assessment ............................................................................ 52 Appendix F – The Green Book .............................................................................. 61 Appendix G – Weed Identification and Controls Poster ...................................... 62 Appendix H – Caustic Cleaning Brine Heat Exchangers Operating Procedure 63 Appendix I – Flora & fauna impact assessment .................................................. 64 Appendix J – EIR - Summary of Comments and Responses .............................. 65 Appendix K – SEO - Summary of Comments and Responses ........................... 66 Page 4 of 66 1.0 Introduction Geodynamics Limited (Geodynamics) plans to maintain and operate its 1MW Geothermal Power Plant (Power Plant) and associated infrastructure and facilities near Innamincka over the next five years to: continue testing and trialling the operation of the Power Plant for research, commercial evaluation and exploration purposes; and maintain and repair the Power Plant and associated infrastructure as required. The plant operates by extracting the heat from superheated (approximately 250˚C) and highly pressurised groundwater (geofluid) derived from a deep (over 4km) enhanced geothermal fracture system in the granite basement rocks underlying the Cooper Basin. The geofluid is produced under its own pressure to the surface via a steel cased geothermal well (Habanero 4) and piped through a high temperature/pressure pipeline approximately 1km to the Power Plant located adjacent to the Habanero 1 geothermal well. The heat in the geofluid is transferred via heat exchangers at the Power Plant into a secondary working fluid, which is used to generate the steam that drives a turbine to generate electricity. The cooled geofluid is then injected into the Habanero 1 well to be returned to the geothermal fracture system to be reheated for the cycle to begin again. Construction and commissioning of the Power Plant and associated infrastructure was carried out under the combined Environmental Impact Report/Statement of Environmental Objectives for 1 MW Geothermal Power Plant at Innamincka (August 2008) prepared by Parsons Brinckerhoff for Geodynamics. Commissioning and trial operation of the Power Plant took place from April to October 2013. Under Regulation 14 of the Petroleum and Geothermal Energy Regulations 2013 (SA), an approved Statement of Environmental Objectives (SEO) must be reviewed at least once in every five years. The Environmental Impact Report/Statement of Environmental Objectives for a 1MW Geothermal Power Plant at Innamincka (August 2008) is due for its five-year review. The scope of the review is based on the requirements of Regulation 14(2) of the Petroleum and Geothermal Energy Regulations 2013, which requires the following to be taken into account or addressed: (a) changes in information or knowledge in relevant areas; (b) community expectations in relation to relevant environmental issues; (c) changes in the use of land; (d) changes in operational practices; and (e) other matters determined to be relevant