China's drive for cleaner mining

Engineer Live News Desk

Demand for rare-earth minerals continues to surge. But could China’s dirty record undercut the environmental benefits of the electric revolution? 
Wind power, solar energy, electric vehicles – we are at the dawn of the green revolution, but there’s a dark side. The new green economy will require copious amounts of rare earth minerals such as europium for energy-efficient light bulbs and neodymium for use in car batteries. At the moment, the global market is dominated by China, which supplies approximately 80% of all rare-earth minerals. Historically, this has come with a significant environmental impact. 

Clean energy, dirty mines 

Rare-earth metals aren’t exactly rare. Many of them are found in similar quantities to more “common” metals such as iron. The problem is that they are difficult and environmentally damaging to extract. There are two main methods to extract rare-earth metals that have been used in China. The first involves stripping layers of topsoil and transporting it to leaching ponds. Here acids and chemicals would separate the rare-earth elements from clay, soil, and rock. The second process requires workers to drill holes into hills and then flush out the earth using water and chemicals before transporting the slurry back to a leaching pond. 

When done improperly, these processes carry significant risks of water contamination and environmental damage. This is exactly what happened in Jiangxi province. A plethora of illegal rare-earth extraction operations led to excessive amounts of ammonia and nitrogen compounds getting into the region’s ground and surface water. There were also significant amounts of lead released during the mining process, posing a health risk. To make matters even worse, much of the mining was done near uranium deposits, which has led to radioactive material in the area. 

Satellite images show that there are large wastewater ponds sitting uncovered and open to the elements. A landslide, not uncommon to the region, could send this contaminated water spilling into the local environment, polluting local groundwater and rivers. This could cause significant problems for populations downstream that use this water as a drinking source. 

Getting the extraction industry under control

Chinese officials claim that a major reason for the problems facing Jiangxi province was illegal mining operations. They have been working to eliminate these operations since 2011 but were only able to complete their efforts in 2017. In 2016, the government also introduced legislation to better regulate the industry – requirements that companies use more modern mining solutions and consolidate waste. But in Jiangxi, the damage had already been done. It is estimated that the clean-up efforts will cost more than $5.5 billion and take up to a century to complete. 
Another challenge for China is that while the industry is highly polluting, rare-earth extraction is vital for the region’s economy. The government is funding efforts to extract rare-earths in more environmentally friendly ways, but these efforts are still in preliminary and likely won’t bear fruit for some time to come. 

More immediately, the government has spent around US$43 million for reforestation in an effort to combat erosion. The problem is that officials from the Ministry of Ecology and Environment have discovered that local governments have been overstating their replanting efforts and that the area treated so far has been exaggerated. 

International effort Is needed 

It is too late for Jiangxi but it is not too late for the mining industry to learn from its efforts. China has 42% of the world’s 130 million metric tons of rare earth reserves. China’s production continues to grow but so does that of a small number of other countries. These countries are looking at increasing their efforts. Doing so could provide economic booms in countries like Mongolia. But the long term environmental costs might prove devastating, as it has in Jiangxi. 

There are a few solutions to this. The first is regulatory. Governments could impose and rigorously enforce strict environmental protections. Combined with emerging extraction technologies, this could help to significantly reduce the environmental impact of any rare-earth extraction operation.

The other solution would be to focus on demand. It is possible, although expensive, to produce electric vehicles with minimal numbers of rare-earth minerals. Indeed Honda achieved this back in 2016. The problem is that this would require a radical retooling of green technologies and could set the green revolution back decades.

A more reasonable solution would be a sustained effort to encourage companies to only purchase rare-metals from sustainable sources, similar to the way palm oil is sourced. 

One thing is certain. Short of some miraculous new technology, demand for rare-earth metals is unlikely to abate any time soon. The challenge will be how we limit the environmental impact of mining operations. We can learn lessons from China. 


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