Strategy Cloudbreak Groundwater Operating Strategy Water
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Strategy Cloudbreak Groundwater Operating Strategy Water Management 30/06/13 CB-PH-HY-0009 Cloudbreak Groundwater Operating Strategy Page 3 of 81 CB-PH-HY-0009 Rev 1 TABLE OF CONTENTS 1. INTRODUCTION ............................................................................................................ 7 1.1 Background ....................................................................................................... 7 1.2 Approvals ........................................................................................................... 8 1.3 Document Scope ............................................................................................... 8 2. ADMINISTRATIVE REQUIREMENTS .......................................................................... 12 3. CLOUDBREAK OPERATING PLAN ............................................................................ 14 3.1 Project Development ....................................................................................... 14 3.2 Dewatering System.......................................................................................... 14 3.3 Conveyance system ........................................................................................ 15 3.3.1 Transfer ponds and settlement ponds .................................................. 15 3.3.2 Bulk flow and conveyance pipelines ..................................................... 15 3.4 Water Supply System ...................................................................................... 15 3.4.1 Ore processing and tailings .................................................................. 16 3.4.2 Dust suppression ................................................................................. 16 3.5 Injection system .............................................................................................. 16 3.5.1 Brackish injection ................................................................................. 16 3.5.2 Saline injection ..................................................................................... 17 3.6 Cloudbreak Village water system and potable water system ....................... 17 3.7 Contingency Operations ................................................................................. 17 3.7.1 Alternative Water Supply ...................................................................... 17 3.7.2 Cloudbreak and Christmas Creek Connectivity .................................... 17 3.7.3 Water supply optimisation .................................................................... 18 3.7.4 Water level optimisation ....................................................................... 18 4. OPERATING RULES .................................................................................................... 19 4.1 Mine water balance .......................................................................................... 19 4.2 Abstraction Licence Allocation ...................................................................... 20 4.3 Injection Licence Allocation ........................................................................... 21 5. WATER INFRASTRUCTURE MONITORING, CONTROL AND MAINTENANCE ........ 22 5.1 Monitoring and controls .................................................................................. 22 Cloudbreak Groundwater Operating Strategy Page 4 of 81 CB-PH-HY-0009 Rev 1 5.1.1 Bulk pipelines and storage ponds......................................................... 22 5.1.2 Leak detection...................................................................................... 22 5.2 Maintenance schedule .................................................................................... 22 6. DEWATERING/INJECTION SYSTEM MONITORING PROGRAM ............................... 23 7. ENVIRONMENTAL IMPACT MANAGEMENT .............................................................. 25 7.1 Potential environmental impacts .................................................................... 25 7.1.1 Overall environmental management approach ..................................... 25 8. TRIGGER LEVELS AND CONTINGENCY PLANS ...................................................... 27 8.1 Project zoning .................................................................................................. 27 8.2 Two-tiered trigger level system ...................................................................... 27 8.3 Framework for selecting appropriate trigger values ..................................... 28 8.3.1 Groundwater level and EC triggers ...................................................... 28 8.3.2 Near-marsh water level assessment .................................................... 28 8.4 Trigger Level Response .................................................................................. 31 8.5 Contingency plans........................................................................................... 32 8.5.1 Insufficient brackish water .................................................................... 32 8.5.2 Insufficient injection capacity ................................................................ 32 9. EFFICIENT WATER USE INITIATIVES ........................................................................ 33 10. MANAGEMENT COMMITMENTS SUMMARY ............................................................. 34 11. REFERENCES ............................................................................................................. 37 12. GLOSSARY .................................................................................................................. 38 Cloudbreak Groundwater Operating Strategy Page 5 of 81 CB-PH-HY-0009 Rev 1 List of Tables Table 1: Key regulatory Issues to be addressed in the Operating Strategy ............ 9 Table 2: Scope changes for this Operating Strategy .............................................. 11 Table 3: Administration requirements ..................................................................... 12 Table 4: Reporting requirements .............................................................................. 12 Table 5: Summary site water balance ...................................................................... 19 Table 6: Groundwater abstraction licence details................................................... 20 Table 7: Groundwater injection licence details ....................................................... 21 Table 8: Cloudbreak monitoring summary .............................................................. 23 Table 9: Near-marsh bore assessment process ...................................................... 29 Table 10: Trigger level framework .............................................................................. 30 Table 11: Summary of licensee’s commitments ....................................................... 34 Table 12: Environmental Impact Management .......................................................... 35 Cloudbreak Groundwater Operating Strategy Page 6 of 81 CB-PH-HY-0009 Rev 1 LIST OF FIGURES Figure 1: Regional Location Plan ................................................................................. 40 Figure 2: Existing Cloudbreak water management infrastructure ................................. 42 Figure 3: Hydrogeological section ................................................................................ 44 Figure 4: Regional production bores ............................................................................ 46 Figure 5: Injection bores ............................................................................................... 48 Figure 6: Monitoring location plan ................................................................................ 50 Figure 7: Cloudbreak trigger level zones and monitoring bores .................................... 52 LIST OF APPENDICES Appendix 1: Groundwater abstraction licences Appendix 2: Tenements Appendix 3: Non-pit region abstraction bore details Appendix 4: Pit-region abstraction setup Appendix 5: Injection bore details Appendix 6: Proposed abstraction rates at Cloudbreak Appendix 7: Cloudbreak conceptual water balance Appendix 8: Monitoring locations Appendix 9: Project trigger levels Appendix 10: Trigger reporting procedure Cloudbreak Groundwater Operating Strategy Page 7 of 81 CB-PH-HY-0009 Rev 1 1. INTRODUCTION The Cloudbreak mine (Cloudbreak) and Christmas Creek mine (Christmas Creek) are located on the southern slopes of the Chichester Range and north of the Fortescue Marsh. Collectively, the two mine sites are referred to as the Chichester Operations. This Operating Strategy relates to Cloudbreak only, for further details on operations at Christmas Creek, approximately 30 km east of Cloudbreak mine (Figure 1), see Christmas Creek Operating Strategy (FMG, 2013). 1.1 Background The water quality in the Cloudbreak area (between the Fortescue Marsh and Chichester Range) is variable due to the influence and mixing of both topographic-driven Chichester Range brackish water and density driven Fortescue marsh saline water. Groundwater in the resource area is generally brackish and becomes increasingly saline towards the Fortescue Marsh and with depth, as shown in Figure 3. Based on the water quality distribution and beneficial use considerations, two classes of groundwater quality are defined for the purpose of groundwater management: • Brackish: ≤6000 milligrams per litre (mg/L), total dissolved solids (TDS), which occurs in shallow aquifer zones within the mineralised Marra Mamba