Mine closure is not just an environmental issue, say Anna Littleboy, Guy Boggs and Glen Corder
WHEN the average person thinks about mining, they consider it to be about extracting minerals and metals that we require for our modern way of life but will inevitability result in damage to the environment. This is undoubtedly true and some environmental impacts from mining can be restored through effective rehabilitation, while others (such as old or abandoned pits) will leave a lasting mark on the landscape. So, when a mine’s ore body runs out and mining is finished, the operator only needs to employ good environmental management to close the site and make it safe, secure, and sustainable, right? No, the answer is more complex than this.
We now know that mine closures should never just be considered an environmental issue, as it is so much more than the rehabilitation of mined land. For mine closure to be successful and lead to a formal relinquishment of the site to a landholder, a business case for the next use needs to be made. This needs to consider post-mining land and asset use based on input from a diverse range of stakeholders in addition to mining companies – local communities, indigenous participation, regional development, provincial and/or national government, and the METS (mining equipment, technology and services) sector. Whilst environmental goals are important, they are not the only issue for this range of stakeholders, who are often seeking to prepare the ground for livelihoods and opportunities for the future.
So we need to consider both mine rehabilitation and lease relinquishment for closure to be successful. How well are we doing it and what’s holding us back from doing better?
Consider three good examples of repurposed mined land. Firstly, at the New Acland mine in Queensland Australia, 650 ha of land has been rehabilitated, with much of this already being returned to cattle grazing land. Secondly, in the Limburg region of the Netherlands, one of the oldest coal mining regions, the government implemented an economic restructuring policy to facilitate post-mining land use and post-mining opportunities. Finally, the Eden project in Cornwall in the UK was developed from an abandoned quarry and contains two large biomes, one which simulates a rainforest environment and the other, a Mediterranean environment. These are all excellent examples of repurposing mined land but none of the three have ever been through a formal process of lease relinquishment. Is this a problem?
The mining industry is maturing, and many mines around the world are nearing the end of their economic life. This is illustrated in Figure 1 where the red, orange, and yellow dots indicate mines that are coming to the end of their economic lifetime within the next five years in Australia. The situation is similar for other mining regions around the world.
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