Around the world, our growing population and our dependence on technology is driving an increasing demand for metals and minerals. From solar panels to mobile phones, lithium-ion batteries to televisions, key elements of our modern lives rely upon specific natural resources buried deep in the ground. And the way to access these materials? Mining.

The industry supports roughly 45% of the world’s economic activities. However historically it has been impossible to carry out large-scale mining without leaving significant social and environmental scars. As demand continues to increase, the concept of sustainable mining has begun to develop. This considers all the impacts of mining activity – the negative side as well as the economic benefits.

Professor Karen Hudson-Edwards is Professor in Sustainable Mining at the Environment & Sustainability Institute and Camborne School of Mines and an environmental geochemist and mineralogist. Her research focuses on the environmental impacts of mining and she works with the industry to help implement more sustainable practices.

Karen says: “A lot of people think about mining as simply extracting something from the ground but in the industry we consider the whole mining value chain from exploration to extracting and processing, to dealing with waste. And there are environmental impacts associated with every step of this process – noise, dust, water usage, chemicals, contamination, deforestation, and waste disposal.

“Mining generates a lot of waste, especially now because most of the really high-grade deposits have been found and so we’re having to exploit deposits with lower grades and therefore more waste. If that waste isn’t stored well we can have elements left behind that are toxic like arsenic, cadmium and lead, or we can have accidents related to the waste. Waste is often stored in a tailings dam, which is an embankment designed to hold materials in with earth and rock, but if they’re not managed properly they can fail. In 2014, 2015 and 2019 there were three significant failings of these tailings dams and when that happens it releases a lot of toxic material very quickly, creating a major disaster.

“There are also social impacts. There is something called the ‘resource curse’ which is where a country has an abundance of resources, but not the means to extract them. So companies from other countries move in, who may or may not employ local workers, but ultimately the wealth is taken out of the country. In some areas, local people suffer from health issues due to mining activity or working in unsafe conditions.”

Sustainable mining focuses on the mining value chain and aims to improve outcomes at each point. There are five key areas to consider:

Economics – mining activity has to make a profit in order to be sustainable as a business practice.

Environment – steps must be taken to prevent contamination of the surrounding area, reduce air pollution and damage to land, water and the biosphere.

Community – it’s important to make sure local people are engaged and involved in projects from the beginning and share in the benefits.

Safety – operations should be designed to protect workers and prevent accidents.

Resource efficiencies – it’s important to minimise waste, and then manage what is generated very well, where possible using it for something else afterwards, or storing it as safely as possible.

Karen says: “We need to recognise that there are negative impacts but at the same time we need mining to sustain modern life. And of course the greater the demand for green technologies such as electric cars, the greater the need for certain minerals. The key thing is to find the optimum balance between extracting assets and protecting the environment and people.

“Sustainable mining is simply about doing things much better and more responsibly. For example there is now a Global Tailings Standard which improves safety and is designed to prevent future disasters, it is now much harder to get approval to mine unless you have a ‘social licence’ where the local community is fully bought into company plans and impacts are reduced, and we also see the public becoming more aware and using their voices – for example with fracking or a recent coal mine development – which pressures for best practice.

“Then there is the extraction itself and here in Cornwall we have quite a few companies doing active exploration while following sustainable practices and thinking ahead. For example we have been working a lot with Cornish Lithium. The demand for lithium has soared thanks to ubiquitous technology such as mobile phones and laptops, and now electric vehicles and other renewables, but the process for extracting it can be quite destructive and we ship most of what we use from the other side of the world.

“Cornish Lithium are working on extracting what is known as geothermal lithium. Cornwall is underlain by granite which is still cooling and while it’s cooling it’s giving off a lot of heat. The rock here contains higher levels of lithium than other granite and it seeps into water. What the engineers are doing is developing a process to extract the lithium from the water.

“This means there is a much smaller footprint on the land, you really just have a borehole to bring the water to the surface and a processing plant. Traditional lithium mining uses a huge amount of water, whereas this method uses a fraction and what it does use can mostly be pumped back underground, and then the reduction in CO2 emissions is really significant. There are other organisations around the world doing a similar thing and it’s really exciting for the future.

“As we transition more and more from fossil fuels we need to make sure the elements we are sourcing instead are not creating their own ecological disaster. This is why expanding sustainable mining practices are so important. And maybe soon our vehicles will be powered by green lithium from under the Cornish soil.”