By Jason Hayes, Associate Director, American Coal Council
First published in Cornerstone, Volume 3, Issue 4
Nearly 8.2 billion tonnes of coal were produced globally in 2014. Although a great deal of activity occurs around the extraction of coal, a limited amount of land is disturbed during mining compared to total landmass. For example, Natural Resources Canada has estimated that less than 0.01% of Canada’s total landmass was used in metal and mineral mining in over 100 years. Similarly, Haigh estimated that mining affected 0.16% of the U.S. landmass from 1940 to 1971. However, even if mining affects a relatively small amount of land, its impact can be significant and the extractive industries have an ethical and often legal obligation to return land to productivity.
Each coal mine has a limited life span due to the finite nature of the resource being extracted. Eventually the resource is exhausted, or the point is reached at which it is no longer profitable to extract for any number of reasons, such as increasing mine depth, increasing strip ratios, changing regulations, or market pressures.
When extractive activities cease, restoration processes must be completed, although they normally begin far sooner. In fact, reclamation processes typically begin while active mining is still occurring in another area of a mine. Thus, mining and restoration can be completed continuously and progressively throughout the life of a mine.
The costs associated with these restoration activities can be substantial: One estimate suggests US$1.5 million per mine, although varied mine sizes, regulatory regimes, or the presence of legacy reclamation costs could result in wide fluctuations in cost.
Today, in many parts of the world, reclamation and restoration plans must be prepared prior to mining. An improved understanding of the potential impacts of industrial activities, societal attitudes toward mining, increasingly stringent regulatory regimes, and dynamic market conditions now typically require companies to state clearly how their operating area will be restored before mining can begin.
There are various approaches to reclamation, and collaborative efforts between industry and government can help to improve mine management and reclamation processes. Thus, best practices and select case studies are worth exploring to highlight examples of successful mine closure and remediation.
The process of reclamation
Reclamation can be roughly defined as the replacement of soil materials—often to approximate original contour—and revegetation of mined areas or areas adjacent to mines that have been affected by mining activities. An alternative definition, offered by the International Energy Agency’s Clean Coal Centre, is “the process of repairing any negative effects of mining activities on the environment”.
Reclamation activities sometimes can also employ passive means of ecosystem restoration—wherein a less intensive management approach is taken and, for example, flora and fauna are allowed to self-colonize after soil replacement and stabilization are completed. However, the vast majority of contemporary reclamation and restoration efforts are based on technical reclamation, which exceeds simply repairing the affected property. Technical reclamation activities often aim to proactively manage a mined area for specific natural or recreational value, or other human uses, which can include infrastructure needs such as airports, schools, or shopping centres. Reclamation activities can also target agricultural or silvicultural (i.e., forestry) objectives. Plans to return mined areas to a more natural state, focusing on soil, vegetative, wildlife, and/or water management values, can also play a large role in guiding reclamation activities.
Both underground and opencast mines require reclamation, but the approaches are different. Reclamation activities for underground mines will typically require less above ground activity, but can necessitate extensive management to avoid drainage and flooding issues after mine closure. This management can involve techniques such as filling of excavated areas with mine spoil or fly ash and diverting or controlling the flow of groundwater to keep it from entering existing mine structures. Doing so avoids the risk of rising water becoming contaminated by dissolved metals and other substances and potentially being discharged into rivers and streams. Notably, higher levels of calcite or carbonates in the rock, however, may neutralize acidic mine water, allowing metals to stay immobile.
Reclamation of opencast mines typically involves replacement of overburden that was removed or repositioned to access buried coal layers. When excavated areas are built up, re-landscaping or recontouring is completed along with drainage control measures. Recontouring will be guided by mine plan objectives (i.e., the intended end use for the land). Where natural processes are sought, recontouring will typically attempt to return landforms to the mine site’s approximate original contour, or to mimic natural contours. Where other human uses are planned for, the land will often be leveled or shaped in a manner that improves access or aids in future infrastructure development.
Ensuring best practices on reclamation
The time frame extending from exploration to post-reclamation and closure requires decades. In many cases, reclamation processes—which can include the mine closure and decommissioning stage, as well as the post-closure stage—can require as long as, or even longer than, the combined previous stages of exploration, site construction, and mining.
Even with mining plans in place, mining can substantially affect local or regional environments. Proper reclamation of mine sites, however, can avoid many risks, including unstable spoil piles, acid drainage and water quality issues, and potential cave-ins.
Best practice reclamation activities are designed to limit or avoid these impacts to the greatest degree possible. Although fully listing the legislative, regulatory, or best practices standards governing global mine reclamation is outside the scope of this article, a few prominent examples are worth highlighting. For example, general requirements for the approval of mining permits could resemble the conservation practice standards published by the Natural Resources Conservation Service (NRCS), U.S. Department of Agriculture (USDA). NRCS describes a threefold purpose for land reclamation:
Australia’s Department of Industry Tourism and Resources gives similar guidance for land reclamation, but also encourages consultation, reporting, and monitoring with stakeholders during mine plan development and mining activities. Companies are also urged to rehabilitate progressively through the full life cycle of the mine and, where possible, to manage and rehabilitate historical disturbances. Expanded regulatory oversight combined with a trend toward a lesser number of larger, mechanized mining operations that are governed by binding mining plans are decreasing concerns about unregulated or unmonitored activities.
Righting the past
Employing best practices during contemporary mine reclamation helps to avoid the challenges associated with mines that were not properly reclaimed in the past. The varied nature of reporting measures and regulatory regimes governing mine management worldwide are compounded by the fact that many private or unregulated mines have been created, especially in developing nations where regulatory oversight may not yet be as thorough. Thus, it is difficult—if not impossible—to get a full count of the number of abandoned coal mines worldwide.
The legacy of abandoned mines, however, is being addressed in many areas. For example, since the passage of the 1977 Surface Mining Control and Reclamation Act (SMCRA) in the U.S., direct fees have been collected by government agencies from existing coal mining companies. Various states and Native American tribes have used over US$4.06 billion of those funds to reclaim almost “240,000 acres of hazardous high-priority coal-related problems”. As described by the UK Environment Agency (2008), six similar programs are being carried out across the UK and internationally.
Collaborative efforts between mining companies and conservation organizations can promote successful mine reclamation as these organizations can lend expertise in developing best practices for wildlife, water, plant, and/or soil management. Demonstrating a transparent working relationship with conservation groups and other stakeholders can also help regulatory agencies when reviewing permit applications. If these agencies observe widespread support for mine plans and objectives and are convinced the area will be properly reclaimed and managed in the post-mining stages, permit approvals can likely be obtained much more easily.
One example of a collaborative effort is the U.S.-based Appalachian Wildlife Foundation’s Mine Land Stewardship Initiative (MLSI), which enables industry to pair with conservation organizations to move ahead in a challenging regulatory environment. The MLSI is working to design voluntary reclamation standards that “elevate the overall ecological performance of the coal industry” and help to enhance:
Efforts like the MLSI are a positive and proactive approach to reduce confusion and litigation, increase stakeholder involvement and buy-in, improve transparency, and ensure the highest standard of reclamation is carried out.
Bonding and financial assurance
Even with proactive management efforts like the MLSI, reclamation can be an expensive endeavour. As the mine will not continue producing saleable material, no additional income will be brought in after operations cease. Therefore, most regulatory agencies require some form of a financial safety net, or bonding, to ensure sufficient funds are available for reclamation even if a bankruptcy occurs. In this manner, company insolvency or an abandoned mine will not impose mine closure and reclamation costs on taxpayers.
While having adequate funds for reclamation is clearly important, public policy must recognize that environmental protection, reclamation in this case, must be balanced with financial realities to avoid stifling economic activity and to allow mining companies to operate profitably. The International Council on Mining and Metals (ICMM) has reported that expectations from an increasingly risk-averse public and government have been forcing assurance costs higher. The ICMM described how, in 1998, a mining company based in Australia had “identified more than 1,056 financial assurance instruments in place in four countries, which represents a contingent liability of greater than AUD$20 million. By 2004 the comparative amount had risen to AUD$60 million". ICMM expressed concern that setting aside growing levels of operating funds in bonds restricts investment and operational flexibility. In fact, increasingly conservative expectations of certainty relating to environmental protection could place such strict financial and administrative pressures on mining companies that mining projects could be cancelled as uneconomic.
Numerous mines around the world are demonstrating successful reclamation projects. One such project is Coal-Mac Mining’s Phoenix #2 surface mine in West Virginia, U.S. The Phoenix #2 mine was the recipient of the U.S. Office of Surface Mining’s 2010 Excellence in Reforestation Award for almost a decade’s worth of reclamation efforts and implementation of the Appalachian Regional Reforestation Initiative’s (ARRI) Forest Reclamation Approach (FRA).
ARRI is a working group comprised of citizen representatives, industry, academia, and government, and was formed to encourage planting of productive trees on reclaimed coal mine lands and abandoned mine lands. FRA is a means by which mining companies and forest managers can improve forest productivity, wildlife habitat, floral diversity, and water management on reclaimed mine lands. The FRA is made up of five steps:
Phoenix #2 mine is a 560-acre (227-ha) operation, originally permitted in January 2001 under the approximate original contour (AOC)-plus backfill guidelines. Under these guidelines, final backfill elevations were established to mimic the natural terrain of West Virginia, avoid soil compaction, and enhance post-mine land use.
Finite resources entail a finite mining life cycle. As coal reserves in a mine are removed or become uneconomical to continue mining, reclamation activities will replace removed soil and/or substrate materials and revegetate the mine in an effort to (1) return it to as close to natural state as possible or (2) redesign landforms to allow improved human access to, or use of, an area.
Key objectives in reclamation activities are to reduce potential damage and prevent negative impacts to the natural environment in and near mined areas, to restore the viability and growing potential of soils to their pre-mining level, and to maintain or improve landscape visual and functional quality.
Reviewing effective examples of mine reclamation from around the globe, such as those profiled in this issue, allows the extractive industry to develop a suite of best practices for successfully reclaiming mined areas. These properly reclaimed mines can provide essential lessons on technology, policy, and collaboration and serve as the gold standard for mine reclamation efforts.
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