Model shows how 4 toxic metals have likely spread downstream from metal mines and waste storage facilities
Metal mining waste have gone down the rivers around the globe leading to about 23mn people being exposed to unsafe level of lead, copper, arsenic and zinc.
Karen Hudson-Edwards of the Exeter University says “We’ve seen a lot of evidence about the way mining can affect river systems”.
The university researcher added that they have decided to model the problem on a world scale and that “The message about chronic contamination of rivers is not getting out.”
Moreover, large amounts of contaminated water gets released in the environment when the tailings dams which hold back mining waste fail, said Hudson-Edwards.The researcher also said that her team’s modelling study stresses the risk due to slower procedures like the sediment and dust which is metal-contaminated, seepage from storage facilities and other procedures. Further, researchers said that more and more people are exposed to contamination which are impacted by tailings dam failures.
The researchers collected data about active and inactive metal mines and tailings dams around the globe. Such information was combined with information about human and rivers from mines and livestock populations downstream. The researchers also modelled the extent of the world’s rivers and land which are likely contaminated with metal mining waste. They have also predicted that 23.48mn people are potentially at risk of being exposed to unsafe levels of arsenic, zinc, copper and lead and that they are exposed through drinking water, dusty air, and food grown on land contaminated.
University of Notre Dame’s environement scientist Richard Marcantonio says that the results are “very, very concerning.” Moreover, the scientist said that the model leaves a lot out.
It does not account for mercury which is a common waste product of gold mining or many metals released when battery materials are mined like cobalt, chromium, and cadmium. The research can also not account for small-scale mining which is dirty and not present in the databases.The scientist’s team is expanding their model to become more comprehensive and that they are limited by available data.
Additionally, climate change is likely to worsen the toxic metals spread. Hudson-Edwards said that the world is getting windier which means it is most important to cover tailings storage facilities and control dust at active mines.
Hudson-Edwards says that a rise in risk of flooding meant that more water to move the metals around contaminated new places but also potentially diluting toxic metals to safer levels. The metal salt formation sped up due to dry conditions caused as a result of more frequent drought.
Hudson-Edwards also said that “Mining is vital now as we’re trying to move away from oil”.
There is a great pressure to create new mines to meet the increasing demand for battery metals.
“It’s in everyone’s interest to make mining sustainable,” said Hudson-Edwards and that she hopes stressing the ongoing risk from historic mining shall make mining companies and governments more alert going forward.
