Seas At Risk advocates the importance of rethinking energy consumption in a no-mining scenario, as well as careful environmental policies. Without a clear vision, controversial biofuel production could fill the energy deficit by converting vast tracts of land to forestry to provide wood as a source for building materials, energy and biofuels.
But the work would not stop there. For Lèbre, who studies mine closures, the closed mines themselves would be a major cause for concern. If all mining stopped, there would still be an area at least the size of Austria with degrading and sometimes dangerous heavy metal levels. “Mining is a process of entropy. We are bringing material from trapped concentrations underground and releasing it into the world.”
Ensuring the cleanup and rehabilitation of these areas would be critical. Mines usually operate at depths below the water table, which must be constantly drained with pumps. When a mine shuts down, over many months, groundwater gradually inundates underground galleries and mineral seams, creating acidic water reservoirs. Above ground, on the other hand, tailings ponds and heaps of low-grade ores with traces of heavy metals lurk. “All of this material is exposed to water and oxygen,” says Lèbre. Exposure of such elements to the elements causes devastating damage to ecosystems, soil and water supplies through acid leaching. “An abandoned mine can be chronically polluted for hundreds, if not thousands, of years,” says Lèbre.
Cleaning a mine consists of reducing water acidity, detoxifying the soil and treating waste before reintroducing flora and fauna to the site. It’s a long, expensive process and can cost billions for a single large mine. Avoiding an environmental catastrophe and cleaning up all the world’s mines at once would cost hundreds of billions or even trillions.
