Leading Practice and Mine Closure Australian Centre for Sustainable Mining Practices

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1 Leading Practice and Mine Closure Australian Centre for Sustainable Mining Practices David Laurence Australian Centre for Sustainable Mining Practices With thanks to Graeme McIlveen and Daniel Franks, SMI, University of Queensland

2 What is Leading Practice? the best way of doing things for a given site It s flexible and innovative in developing solutions that match site-specific requirements. It s about approach and attitude as it is about a fixed set of practices or a particular technology. an evolving target it is adaptive to changing standards and situations to allow mining companies to maintain their social licence to operate

3 Leading Practice Sustainable Development Program for the Mining Industry The Leading Practice Program provides practical guidance to the mining industry through handbooks and workshops Assist with the implementation of leading practice Offering a continual challenge to the industry and other stakeholders to improve their social & environmental performance

4 Leading Practice Sustainable Development 14 HANDBOOKS PRODUCED TO DATE Community Engagement & Development Managing Acid & Metalliferous Drainage Mine Rehabilitation Mine Closure & Completion Stewardship Biodiversity Management Tailings Management Working with Indigenous Communities Water Management Cyanide Management Risk Assessment & Management Hazardous Materials Management Evaluating Performance: Monitoring & Auditing Airborne Contaminants, Noise & Vibration

5 The Guide to Leading Practice

6 The Guide to Leading Practice This new publication provides a single point of reference for information on implementing and improving leading practice principles through the life of a mine by bringing together the major lessons of the leading practice books and case studies from around the world.

7 Why Do Mines Close?

8 Reasons Why Mines Close Mines close! Resource depletion: ideal case Economic: cost or price changes Reserves and resources: uncertainty or errors Transition from open pit to underground Geological issues: unpredictability or errors Geotechnical problems: instability, stresses and failures, hardness Mining technical: rock hardness, errors in choice of technique Metallurgy: unpredicted mineralogy effects, errors in choice in technology Safety and health: fatal accidents Flooding Change in corporate ownership or strategy Loss of markets Community opposition Government intervention Combination of these reasons or factors

9 Mine Closures % Percentages of Closures 25% 20% 15% 10% 5% 0% Resource Depleted High costs/low prices Receivership/administrator Open cut depleted Geology/geotech issues Did not fit company strategy Low grades Loss of markets/downstream Regulator/government interv. Floods/wet weather/inrush Production difficulties Equipment/technical difficulties Lack of exploration Safety Environment Poor grade estimation Industrial relations Metallurgical Unclassified Primary Reason for Closure School of Mining

10 The Impacts

11 Mine Closures Primary Environmental Impacts AMD Tailings Open pit voids Waste dumps Water quality Land/soil degradation Poor rehabilitation Infrastructure Underground impacts general Rivers/creek impacts Heap leach issues Slope stability Heritage issues Aesthetics Others School of Mining

12 AMD

13 School of Mining

14 Tailings

15 School of Mining

16 School of Mining

17 Waste rock dumps

18 School of Mining Mine Closures Socio-economic impacts Employees 10% 7% 5% 2% 2% 40% Regional/local (businesses etc) Indirect employee Sterilised ore 12% Loss of investment 21% Industry image Death/loss of community/town Indigenous opportunities

19 School of Mining Employees Major stakeholders often neglected

20 Indigenous community Failed joint ventures Trust? School of Mining

21 School of Mining Mine Closures Primary OHS Impact Vertical openings 9% 18% 36% Voids Subsidence Landslips Hazardous materials 9% Other 9% 18%

22 School of Mining Vertical openings From drill holes to shafts to

23 Open pit voids School of Mining

24 Subsidence Block cave & SLC; Crown pillar collapse Longwall School of Mining

25 School of Mining Subsidence

26 School of Mining Longwall damage Courtesy A. Waddington & BHP-Billington

27 Hazardous substances School of Mining

28 Legislative and Policy Requirements for Mine Closure Australian legislation and regulation are both national and state-based: Nine states and territories Minerals are reserved to state governments Conditions for mine closure and rehabilitation are set at state level National laws address national issues such as impact assessment and exports, but not mine closure or rehabilitation directly National Environmental Protection Measures, such as for hazardous waste National Strategic Frameworks for mining (guidance documents) on Tailings Management, Abandoned Mines (legacy sites), Water Management and Mine Closure State and Territory laws address mining, land use planning and pollution control State laws address mining title and conditions, management plans and financial guarantees for mine closure and rehabilitation State pollution control regulation is detailed and onerous, with financial penalties not in mining law

29 Regulatory and Planning Issues for Mine Closure Key elements: Predictability and availability of Policy guidelines Consistency and scientific rigor in enforcement Resources for enforcement Future may lie in risk-based and non-prescriptive approach to regulation Being in compliance is mandatory requirement for certification in ISO14001 Pressure to publish information on closure liabilities in sustainability reporting Resources and guidelines: State Guidelines Leading Practice handbooks Research and training

30 National Strategic Framework for Mine Closure

31 PLANNING ISSUES AND APPLICATION OF RISK MANAGEMENT The importance of risk and of management of risk as the key management tool Critical aspects and impacts of the mining cycle (closure and rehabilitation) are risks to be managed They can be managed using new research-based risk methodologies Closure risks For the company Corporate risk, reputational risk and business risk (liabilities) Operational; compliance, environmental liabilities For the regulators Long-term liabilities Financial Guarantees [performance guarantees] For the community Economic development and employment issues Long-term environmental impacts and liabilities Planning and Risk Assessment are essential steps in mine closure

32 Manage the Risks for Mine Closure

33 What are the Risks of Mine Closure and how do we manage them? The likelihood that an event will happen and the consequences of that event happening Our aim is to make ourselves aware of all the risks, to understand all the risks and to manage them systematically We can develop a risk matrix and quantify the risks allowing us to rank them, to cost them and to prioritize them We can design control strategies for risks, we can insure against them or we can accept them

34 Planning, large scale open pit coal mining Mt Owen Coal Mine, Hunter Valley, NSW

35 FINANCIAL GUARANTEES [Performance guarantees] Financial Guarantees, Bonds or Securities are aimed at penalising failure to adequately rehabilitate closed sites Form of risk assessment and management Forms of guarantees: insurance, up-front bonds, bank guarantees Regulator methodologies are not systematic Policy guidelines available

36 Financial Assurance for Mine Closure

37 Financial Assurance for Mine Closure

38 Leading Practice Handbook: Mine Closure and Completion

39 Domains

40 Mine site domains and elements Planning principles for each domain Voids and open pits Understanding the long-term geotechnical and hydrogeological behaviour of the pit walls Water balance Waste Rock Planning shape natural and final Planning encapsulation and optimization of mass handling Water balance and surface hydrology and infiltration Run-off and erosion Soils and plants: store and release example

41 Mine site domains and elements Tailings facilities Final design and capacity Settlement and consolidation Outer slopes and surface covers Potential for AMD Processing and Plant site Hazardous waste Soil contamination Demolition and recycling Final use Heritage aspects

42 Leading Practice Handbook: Mine Closure and Completion

43 Progressive rehabilitation Mt Owen Coal Mine, Hunter valley, NSW

44 Large-scale open pit coal mining in State forest, Hunter Valley, NSW

45 Closed mines and Legacy Sites Variously termed Orphan, Derelict, Abandoned and Legacy sites Unrehabilitated Serious risks to public safety Contaminated land Health risks Environmental impacts Contaminated waterways Health risks Environmental impacts Heritage and Tourism issues Social connection with local communities Economic connection with local communities

46 Mining heritage and tourism Mt Morgan gold mine, Queensland, and Sovereign Hill gold mine, Victoria

47 LEADING PRACTICE IN MINE CLOSURE and REHABILITATION Key Messages All mines close and many close prematurely. Mine management needs to develop and implement mine closure planning. Taking more integrated approach to mine closure planning, and doing it earlier, can achieve effective mine closure and completion, and ameliorate negative effects of unexpected or unplanned closures. Community engagement at earliest possible time is essential. Goal should be community ownership as community will inherit project eventually. Community liaison or advisory groups established specifically for mining project can help operation focus its engagement program. Rehabilitation planning and implementation need to take place early and progressively throughout life of mine. Leading practice techniques can provide guidance for successful landform design, topsoil usage and revegetation outcomes.

48 LEADING PRACTICE IN MINE CLOSURE and REHABILITATION Key Messages Costing for closure and rehabilitation is essential and tools are available to calculate realistic costs. Risks (to company reputation etc) are significant and are long term in nature and companies can expect to have rehabilitation and closure liabilities long after production has ceased. Quantitative and qualitative risk assessment techniques to demonstrate to community and regulators that closure issues have been identified and appropriate security deposit can be calculated. Leading practice biodiversity management goes beyond minimising long-term impacts from operations. It identifies opportunities for improvement in lease and adjacent areas by introducing innovative and sustainable land management practices. Leading practice techniques during operation of mine will reduce potential for long term issues associated with acid mine drainage.

49 LEADING PRACTICE HANDBOOK: BIODIVERSITY MANAGEMENT

50 Measuring the height of saplings, rehabilitated land University of Newcastle researchers, Mt Owen coal mine, Hunter Valley, NSW

51 Ongoing assessment of the success of rehabilitation Kidston gold mine, Queensland

52 Closure: What does it mean to leave a positive legacy? Leaving a positive legacy means that the region around the mine and the people who live in it are left with assets that have value beyond the life of the mine. It is not just about mitigating the negative impacts of closure Assets may take a variety of forms and will not necessarily be physical, economic or fixed in one place.

53 Mt Leyshon & Agricola courtesy SMI

54 The Guide to Leading Practice

55 The Guide to Leading Practice

56 The Guide to Leading Practice

57 New England Sapphires (1990)

58 New England Sapphires (2012)

59 New England Sapphires Excellence in enviro management Suitable final land use Regular information sharing with landowner Pay the landowner well Invited onto other farms for exploration , 5 mines successfully closed

60 Thank you for your kind attention