Waste Management Outlook for Mountain Regions

Tailings stored in dams and impoundments are theoretically supposed to remain forever, but in reality many storage facilities fail. When mines were small-scale operations, the storage of tailings was not given a lot of consideration and waste was stored poorly or just dumped into valleys or rivers (and there are many old abandoned mine sites that cause environmental damage today as tailings do not necessarily become “safer” with time). Improved technology has made it economical to mine progressively lower grade ores, resulting in larger mines and the production of more and more tailings that need to be permanently quarantined from the environment. A review of major tailings dam failures in the period 1910 to 2010 by Bowker and Chambers (2015) found a trend towards failures of increasing magnitude and negative impact, and concluded that the scale of future disasters could require cleanup operations that were beyond the economic capacity of mining companies. Some of the largest mines in the world, and consequently the largest waste dumps, are found in mountain regions and statistically it appears that some of these storage dams will fail in the future (Morgenstern et al 2015). The 2015 dam collapse at the Germano iron ore mine located in ranges of Minas Gerais in southeastern Brazil, illustrates the social, environmental and economic impact of a giant dam failure. The collapse flooded the village of Bento Rodrigues killing 19 people and spreading toxic red mud for more than 700 km across two states (Hatje “Reference document on Best Available Techniques for Management of Tailings and Waste-Rock in Mining Activities”: In 2009, after an accident in Baia Mare (2000), Romania, the European Commission released this document, which as the name suggests describes best available techniques for mining of the metals, coal and selected industrial minerals. It includes rock-waste management and tailings management (European Commission, 2009) “Safety guidelines and good practices for tailings management facilities”: The United Nations Economic Commission (UNECE) for Europe issued this report in 2010 to supporting policymakers and the business sector in enhancing awareness and the sharing of experience and good practices among the competent authorities, operators and the public. Another aim of this document is the better harmonization of the regulations and requirements

2016). If a failure of this magnitude occurred high up in the mountains the consequences could be even more devastating and geographically extensive.

Perpetual waste: Waste generated after the mine has closed

Mine restoration in mountain areas is difficult due to the steep slopes, often thin, poor topsoil and high intensity rainfall events. In addition, disturbed areas can be very extensive - open pit mines constitute some of the largest man-made structures. Some mine sites are just abandoned, with no attempt at restoration – this is especially common inareas that haveexperienced informalmining, in developing countries and or mines in developed countries that operated prior to effective environmental legislation. Without restoration, abandoned mine sites experience long-term erosion and leaching from tailings impoundments and waste rock dumps. Hard rock mines (associated with ores containing sulphides and minerals like gold, silver, iron, copper, zinc, nickel, tin and lead) can also be a source of environmentally damaging acid mine drainage. Long after the economic minerals have been exhausted, acidic waste can still be generated from the mine, stored tailings and exposed rock. When iron sulphide minerals, common in many mineral deposits, are exposed to air and water, they react to form sulfuric acid and dissolved iron (the iron can precipitate, forming

Examples of some existing best practice guidelines, documents and initiatives related to mining waste

concerning the safety of tailings management facilities (TMF) in the ECE region (UNECE, 2014)

“Best Practice in Environmental Management of Uranium Mines”: the International Atomic Energy Agency (IAEA) released this document in 2010 with the objective to provide both operators and regulators with guidelines and examples of the implementation of the principles of best practice to the uranium mining and processing industry. (IAEA, 2010) International Council on Mining and Metals (ICCM): ICMM is an international organisation whose goal is to improve the social and environmental performance of the mining and metals industry. ICCM brings together 23 mining and metals companies and 34 regional commodities associations, identifying common challenges and working to establish a safer and more sustainable industry. (ICMM, 2016)

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