Mining — The Necessary Evil of Our Time?
For outsiders looking inwards on the world of mining, it seems like a fairly miserable industry. Not for those who work in it of course, they make a lot of money. Yet, objectively, mining has been an incredibly destructive industry. The “sustainability transition” within mining is focused on figuring out how to make an evil thing acceptably evil.
Regardless of how we feel about mining, there is always the familiar array of arguments in its favor: “humanity has been mining for millenia,” or “we all benefit from it,” or, my personal favorite, “the laptop you’re using to read this needs to come from somewhere.” Sure, none of these are explicitly false statements, yet they ignore the crux of today’s mining industry.
Mineral reserves are at a historic low with minerals such as Indium, Gold, and Copper predicted to be completely exhausted by the end of the century. But we desperately need these minerals if we are to get anywhere near accomplishing international carbon emission targets.
Mineral extraction is a function of price. Mines will only extract what is deemed economic to extract and then close, but as supply of critical minerals constricts drastically and demand for others, i.e. lithium and cobalt, rises, prices rise in turn.
So are we actually running out or is that just something people say to spike prices? Well…yes. Mineral exhaustion effectively funds the development of new, more efficient mining techniques which then helps meet huge global demands — and fund the private jets of mining executives.
One such new technique, In-Situ Leaching (ISL), is the source of much discussion. ISL is a type of mining where, after an orebody is identified and established as a viable reserve, a field of wells is set up above ground. These wells pump a lixiviant, typically something very acidic or very alkaline, to strip orebodies of target minerals and extract the solution for processing.
ISL is the global standard for the extraction of uranium. The United States and Australia host firms currently piloting the development of ISL for the extraction of copper and other critical minerals. ISL could help the mining industry become less physically destructive, though, does this make it more sustainable?
There is no digging. All the trademarks of mining — explosives, open pits, dust, massive dams of waste rock (tailings) — are absent. ISL mines can theoretically produce a mineral concentrate in absolute silence.
Of course, there are limitations. Orebodies need to be permeable enough to let lixiviants percolate efficiently. Groundwater contamination is a serious, but manageable, risk. Despite these limitations, the concept of leaching remains applicable to the more run-of-the-mill, destructive mines as well.
Indonesia is an apt example. The country houses extensive nickel reserves. Nickel is one of the key minerals used in the construction of high-performance batteries and Indonesia could produce up to 60% of the global supply by 2025.
Mining companies in Indonesia are opting to process nickel-hosting ores with a variation of ISL known as High-Pressure Acid Leaching (HPAL). HPAL does not replace the digging up of nickel, but it replaces the 1500°C furnaces used to process ores and produces a nickel product very suitable for batteries.
Mining in Indonesia means destroying rainforests, regardless of what kind of mine you want to build. More than 50% of the country is forested and these forests are some of the world’s biggest carbon sinks. Additionally, ISL is still an energy-intensive process and the primary source of energy in Indonesia is still coal.
A mine is only as sustainable as the energy it consumes. The rest of mining is really the antithesis of sustainability is it not? Once something is out of the ground and put into your cell phone, a car, or even the Colosseum, it’s a little difficult to put it back where it came from for your grandkids to dig up.
