There is a perception that mining is inherently dirty and destructive. And it is true that the industry is faced with big challenges when it comes to environmental and social impact.
Yet mining is critical to provide the minerals and metals we need today and, in the future, to support low- and no-carbon energy, manufacturing, construction, information technology, green technology and transport.
It’s essential for the greater good: supporting human lives, our economies and efforts to create a more sustainable world. But balancing the benefit versus the cost and impact of mining is a complex negotiation and the arguments surrounding the topic are nuanced.
Meanwhile public discourse, media headlines and brand positioning around the sustainability debate are often firmly black and white. Or perhaps washed green.
So what questions should we be asking about mining and sustainability?
We asked Martijn Mannot-Russell, Technical Director experienced in mining and construction at OTB Engineering, for his perspective.
Engineering has always been about delivering the best solution. And that means a solution that is safe for people and the environment, does the required job and at the right cost.
In the past, with the technology, materials and calculation models that were available at that time to the famous infrastructure builders such as Brunel, the Victorians arguably over-engineered many structures. However, with the tools we have at our disposal today such as finite element analysis, well researched models engineers can push designs to leaner limits, at the same time ensuring that they are safe and effective. This enables a reduction in the quantities of materials used and combined with the latest technology, ensures that the structures are more durable, and therefore more sustainable.
Remember that the Prince Albert rail bridge over the river Tamar in Saltash, Plymouth still operates today – the steel structure was built in 1859, so that’s 164 years old and still going strong.
It is inherent in the role of mining and civil engineering to seek to create solutions that use less concrete, less water, have as minimal as possible negative effects on local environments and communities. And to deliver back as many social and environmental benefits as possible.
“We've always been trying to reduce the carbon footprint. We've always wanted to use less cement. We’ve always wanted to use less steel. Civil and construction engineers always want to reduce their materials. It is to do with cost too, of course, but it’s always been an underlying motivation.”
Those efforts may previously have been described purely in financial cost management terms, but they were also delivering sustainability benefits, then and now.
What has the mining industry been focused on when it comes to sustainability?
“In the last 10 years, the mining industry has led the way with electric vehicles. When you’re underground air quality is critical. So do I go with a big diesel engine, very powerful, great system, but it kicks out loads of fumes, or do I focus on an electric vehicle, which has no exhaust? If you use electric systems, you can reduce your air inflow and while you do still need to power and recharge batteries, you can use less energy for ventilation.”
Many mines are embracing renewable energy sources - particularly in rural areas in Australia and Africa, where there's lots of space available - they are using solar panels, where possible to supplement energy and rely less on generators or on the grid.
Mining companies are also looking at using chemicals and alternative binders in mine backfill operations. This reduces their reliance on cement which is expensive in terms of energy used to make it as well as financial cost.
Tailings (waste materials from mining & processing) are a big challenge for the mining industry. New mining concessions are now often issued with the caveat that tailings must be processed and where possible disposed of in underground mined out voids/spaces to reduce the surface footprint of the mine. And there are continual efforts to improve the methods of extracting the maximum amount of minerals and metals - and therefore value - from the tailings as possible.
This is not to say that everything that can be done is being done. But the industry is focused on finding ways to use less, decrease negative impacts and improve the environmental and social value it can deliver.
“On the one hand, the world is increasingly digitising and electrifying tools and processes in the interests of productivity as well as sustainability. But those decarbonisation-through-electrification efforts are also increasing the demand for metals. Higher demand means higher metal prices which makes more mining operations viable. So that's good for mining but beyond that industry we really also need to have a better take on recycling metals or products that are currently in use.”
What of the future?
For Mannot-Russell, civil and mining engineering have a crucial role to play in sustainability.
The industry is continually working with new knowledge and tools: using plastic fibre reinforcement produced from recycled plastic and steel fibres to reduce the need to fabricate new steel. Exploring new and different products to reduce the lining thickness for tunnels. Creative approaches to project management and construction to reduce environmental impact and waste by the equipment used plus develop new methods to use less.
Change has to come from the inside of any industry, the future is in the hands of the next generation of engineers of all disciplines. From the mining engineers producing the raw materials, the civil engineers who use those materials for construction, the material engineers and mineral processors to discover new innovative methods of extracting metals, combined with mechanical and electrical engineers to develop new uses and applications.
“If you truly care about your environment, if you truly care about sustainability, then become a civil engineer or mining engineer. You’ll be surprised how much change is going on. But we need more really creative people to help us take it further.”