Nothing lasts forever planning for successful mine closure

Transcription

1 Nothing lasts forever planning for successful mine closure Tommi Kauppila, Geological Survey of Finland

2 All mines eventually close All mines have a finite life-of-mine (LOM): Eight years for a typical gold mine starting now Thirty years for a typical copper mine Mine sites may leave an environmental legacy that persists after mine closure Slow weathering of mineral wastes; Acid Rock Drainage Water management issues Mine closure also affects the regional economy and livelihoods Also a wealth of opportunities for the post mining period EXPLORATION (20+ yrs) PRODUCTI ON POST CLOSURE (10- eternity) CONSTRUCTION (2-3 yrs) CLOSURE (2-3 yrs)

3 What is mine closure Mine closure aims at bringing all parts of the mine site to a safe and physically, chemically and biologically stable state that facilitates the planned post mining uses of the site. Mine closure consists of two main activities: Decommissioning = permanently ending the mining and mineral processing operations and removing all the equipment and facilities that are not destined to remain in place for future use Reclamation = reclaiming the mine site for the planned sustainable post mining land uses Mine closure starts already at the planning stage of a mining project and continues long into the post mining period

4 Mine closure is a long process Interact with feasibility and planning Consult stakeholders Define post closure land uses Define closure objectives Make a Closure Management Plan Keep the CMP up to date Exploration Pre-feasibility Feasibility Financing Design & planning Constru ction Operate for closure Employ continuous closure Make the final CMP Close the mine Monitor success Operation Decision to close Final closure Post closure

5 Stakeholders are key to successful closure External stakeholders Those affected by, dependent on, or interested in the mining project. Those in a position to affect the outcomes of the closure Can provide a view of the post mining land uses and life in the area Local residents, summer home owners, municipalities, authorities, NGOs, prospective post mining users of the site Internal stakeholders Those whose work in the project affects the success of the closure process Mine closure should guide all planning, design, and operation: clear and well communicated objectives Environmental department, Health and Safety, Mining, Processing, Geology and Exploration, External relations, Financing; the corresponding departments at the corporate level

6 Objectives of working with external stakeholders Remind stakeholders that all mines close at some point and preparations are needed to sustain the benefits after closure Identify the most affected stakeholders and those crucial for successful closure Provide information to facilitate the participation of the stakeholders in the closure process Look at risks but also opportunities related to mine closure Collect, combine, understand and balance the views, expectations, and objectives of the different stakeholders Define balanced and realistic objectives for mine closure and views of the post closure uses of the site Engage stakeholders in the closure process to achieve best sustainable mine closure outcomes

7 Defining closure objectives: minimize risks, maximize opportunities

8 General closure objectives Value/objective Physical stability Geochemical stability Biological stability Aesthetics Natural resources Post-mining land use Social and economic issues Closure objectives All remaining structures and facilities are physically stable, able to withstand the environmental conditions and events, pose no threat to health and safety, and term functions as designed. Any contaminants must not be released and transported from the site at harmful to human health or biota or otherwise unacceptable. The biological environment is restored to a natural, balanced, self-sustaining the area or compatible with the planned post mining land use. The other mine must provide for physical, chemical, and hydrological conditions that enable such ecosystems. The site is brought to a visually acceptable state. Closure secures the amount and quality of the natural resources of the site mineral, energy etc.) Closure and reclamation are such that the desired post-mining land use is mining land uses have been selected using best practice approaches. Closure minimizes adverse local and regional socio-economic effects and seeks benefits. The views, expectations, and expertise of the local community are taken consideration. Financial issues Outstanding liability and risks are minimized after reclamation activities are are in place to facilitate post closure monitoring.

9 Closure Management Plan is a key document Closure Management Plan (CMP) is a key document in managing the closure process Many jurisdictions, including Finland, require a closure management plan as part of the permitting process The actual live CMP is usually a different document The level of detail increases throughout the project Conceptual Detailed Final ; engineering design, management procedures, due diligence CMP is a continuously updated document with the aim of providing confidence that the closure objectives will be met Constant reduction of uncertainties and outstanding liabilities

10 Legal requirements in Finland there must be a plan Mining Act, Section 120 & Government Proposal for Mining Act (HE 272/2009) The mining operator must take into consideration the safe termination of mining activity at every stage of the mining project. The termination of mining activity and the closing of the mine should be conducted in a planned manner. The Government Decree on Mining Activities (391/2012), Section 16: The mining application must include a reliable report regarding the termination of activities and related measures, alongside after-care measures to be performed once the mining activity is terminated A report on the measures required by the termination of mining activities and their regional scope. A report on the measures related to buildings and constructions after the termination of mining activities. A report on the objectives and primary content of mine closure measures. A report on the options available for the area s future use. An estimate of the schedule and costs of termination measures

11 Benefits of a Closure Management Plan Public participation: Public participation is essential to successful closure planning. Closure planning usually starts early in the project, at the same time with the EIA process, and relies heavily on the views of the stakeholders on what the post mining uses of the proposed mine site should be and what is their view of the local community after the mine has closed. Predictability: Commonly agreed goals for mine closure help in reducing uncertainties about what is expected from the closure process. This, together with appropriate planning and costing of the actions needed to fulfill the goals, helps in estimating the costs of closure and including the costs on balance sheets. Continuity: Changes of ownership and management are frequent in mining. A Closure Management Plan helps in maintaining the original goals and focus through these changes all the way until the end of the operations. Prevention is better than cure: The CMP defines the physical, chemical and biological conditions of the site that facilitate the agreed post mining land uses. It is usually less expensive to achieve these conditions by preventing pollution and problems of physical stability during planning and operation of the mine than to try to fix the issues at the closure phase. Continuous closure: The most common approach to mine closure is that of continuous closure in which closure actions are taken throughout the life of the mine. For instance, individual waste facilities or sections of facilities may be closed years before the cessation of mining. Continuous reduction of risks: Perhaps the most common form of continuous closure is reduction of risks and unknowns related to closure during the operation of the mine. For instance, long term weathering tests of tailings materials and cover structures are often made and the facilities that have already been closed are monitored to estimate the performance of the closure methods. Financial issues: Many jurisdictions require financial sureties to guarantee that enough funds will be available for mine closure at all times. Mine closure plans and the cost estimates involved can be used to define the amounts of funds required for closure and, with continuous closure, the estimated costs of the remaining closure actions. Demonstrating closability: An up to date CMP can be used to demonstrate that the mine can be closed safely at all times during operation. It also serves as a basis for planning the mine's transition to care and maintenance if that becomes necessary.

12 Closure Management Plan & Action Plan Contextual information Purpose, scope and status of the plan Site operator (especially for official CMP documents) Site characteristics Legal obligations Closure management Management structure and responsibilities CMP Review schedule and procedures Commitments related to closure (if appropriate) Target outcomes of closure (objectives) Stakeholder consultation Analysis of risks and opportunities Post mining land uses Identification of closure issues to define closure objectives Scope of the CMP and the closure Closure objectives (=goals), interim goals (milestones), verification

13 Closure Management Plan & Action Plan Action plans How the individual objectives will be achieved Which issues need to be addressed to achieve the goal For each closure issue: Actions, timing, responsibilities, resources, costs Monitoring of success Costs of closure and financial arrangements Full costs of closure (estimate, incl. variation) Estimated cost schedule Financial arrangements, reference to surety Post closure management plan May be one section of the Action Plan or a separate plan Annexes Detailed plans for the actions listed in the Action Plan Reports etc. of the completed actions

14 Action Plan (Tailings Management Facility B) 2: Tailings Management Facility B Task no Action Timing Responsibility Resources Verification Cost Feasibility study Site environmental Siting 2-01 Preliminary siting of TMF B Pre feasibility manager officer + team approved $ Conceptualise post closure use Feasibility study Site environmental 2-02 and land forms Feasibility manager officer + team Report $ Site environmental Feasibility study officer + team + Report 2-03 Feasibility manager consultant approved $ Conceptualise and list cover structure options Study the geological, hydrological and geotechnical data of the TMF B site Contribute to engineering design of TMF B Compare final TMF B structures to planned and update CMP Design long term field tests for tailings materials Site environmental Site environmental 2-04 Feasibility officer officer + team $ Planning and Site environmental Review final 2-05 construction officer Environmental team design docs $ Site environmental 2-06 Construction officer Environmental team CMP updated $ Site environmental Environmental team 2-07 Startup phase officer + consultant Test plan $ Startup phase, Site environmental Environmental team Annual 2-08 Start long term field tests annually officer + consultant reports Design long term field tests for May 15th Site environmental Environmental team Approved 2-09 tailings covers 2018 officer + consultant report $ etc. etc. etc. etc. etc. etc. etc. $ $ /a (analyses)

15 Financial provisions for closure Mine closure requires considerable resources and funding. These costs should be taken into account already in the feasibility planning stage. Financial sureties are often employed to ensure that enough funds will be available for mine closure at all times Usually required in legislation. Sometimes separate for waste facilities. Determination of the correct amount is excessively difficult Enough but not prohibitive Default: Closure in absence of the mine operator The scope of the surety needs to be clearly defined as well CMP is of great help here Should not be a substitute for proper mine closure but an incentive Reduction of liabilities with continuous closure

16 CMP is kept up to date Three main ways of doing this Regular intervals The most common way; legislation or permits may require this Financial department surely likes this (reduction of liabilities) With changes in the project With new data or more advanced planning stage One of the main goals of the closure process is constant reduction of risks and uncertainties This is why many of the actions in the Action Plan aim at reducing unknowns already during operation Utilization of monitoring data Specific research and field tests to aid in closure planning

17 Updating CMP with project changes

18 Mines are operated for closure The idea behind Closure Management and regular updating of the CMP is to make sure that the mine is operated for closure. Designs, plans and operation should not jeopardize the objectives of closure but contribute to them The principle of continuous closure: close what you can when you have cash flow, personnel, and equipment in place Mines have to be able to prove that they can be closed safely at all times Especially important during long lasting care and maintenance periods Continuous reduction of risks, unknowns, and (financial) liabilities

19 The final closure phase and post closure monitoring The final closure phase starts with the decision to end mining This usually gives a maximum of a few years to prepare for final closure Transition from the operational phase to decommissioning and final closure: Technical planning for decommissioning and reclamation Making sure that all agreements related to closure are fulfilled Monitoring is employed to verify that the objectives of closure have been met and no environmental or social risks remain In some jurisdictions monitoring is required for relinquishment Some post closure maintenance is usually required (e.g., passive water treatment structures) It is advisable to analyze the closure process afterwards to learn from it

20 Thank you! mineclosure.gtk.fi