November 01, 2023
The Mining Microbiome Analytics Platform is finding tiny solutions to some of our biggest environmental challenges
*The following is an excerpt of an article originally published by Illumina. To read the full article, please visit Illumina.com.
Selenium, element 34 on the periodic table, is essential for animal cell function—in small amounts. But just like oxygen and water, a high-enough concentration of selenium can become toxic.
Selenium occurs naturally in coal deposits and sulfide ores, like brassy chalcopyrite and crystalline sphalerite, which are important resources for copper and zinc mining. The mining process creates leftover rock, and water from rain or snowmelt that flows through this rock can carry selenium into nearby waterways. Plankton absorb the element directly into their tissues, and fish that feed on that plankton can potentially get enough selenium in their bodies to cause growth defects. It’s incumbent upon the mining industry, then, to find innovative ways to manage selenium and protect fish populations in the communities where it operates.
Renewable energy needs mining
For generations, the metals and minerals that the mining industry produces have been integral to improving quality of life. And the industry is on the cusp of a staggering increase in demand for materials critical for low-carbon and renewable energy technology.
“What we’re producing are the fundamental building blocks of society,” says Bryan Rairdan, technical director of processing at Teck Resources Limited, which has mining operations in Canada, the United States, Peru, and Chile. “With current technology, if we want to densify cities, we need steel. If you need steel, you need steelmaking coal. If you want to electrify the world, the best way we have to move those electrons around is copper.”
A single wind turbine requires 4.7 tons of copper and 335 tons of steel—and to meet net-zero emissions goals from now until 2050, the world will need as much copper as humanity has mined since 1900. Considering that mining is crucial to building green energy infrastructure, what can the industry do to advance its environmental performance?
Bacteria can keep potentially harmful amounts of selenium from entering rivers by changing it into selenite crystal. Credit: istockphoto
Tiny creatures can have a big impact
As it turns out, some bacteria can “eat” selenium—or rather, their carbon metabolism has evolved to convert the element from its dissolved state into a more solid form, which is then easier for humans to keep out of the water cycle.
At its steelmaking coal mines in the Elk Valley of British Columbia, Teck has built “saturated rock fills,” which are large pits of waste rock allowed to fill with groundwater and treated with these special bacteria to reduce selenium levels in the watershed.
Teck’s water treatment facilities, including its saturated rock fills, are working. This treatment is removing between 95% and 99% of the selenium from treated water, and monitoring shows that selenium concentrations downstream of treatment have stabilized and are reducing.
Microbes can make mining itself more environmentally friendly, too. While most copper is obtained through furnace smelting, which contributes to air and water pollution, about 20% of the world’s copper now comes from hydrometallurgy, which uses strong acids and, increasingly, bacteria that can naturally leach the metal.
Bill Burton, principal geological/geotechnical engineer and H3 R&D lead at BGC Engineering, says the potential for microbial applications in mining is exciting. “There’s a goal in the industry for mining to be a temporary use of the land. You have to manage the waste and byproducts that come from the process, and there are many places where microbial biotechnology can help with that.”
For example, Rio Tinto, a mining company operating on six continents, has supported multiple R&D projects to finding biotechnological ways to recover metals from mine-influenced water. And Elizabeth Deyett, senior bioinformatics scientist at Allonnia, explains that some microbes can be used to help dust suppression by binding fine sand particles together, making the air safer to breathe; others can be used to help mining companies extract certain metals they weren’t looking for before, like rare earth elements that are essential to many green technologies, such as energy-efficient light bulbs and hybrid vehicle batteries.
How many other kinds of industry-changing organisms might be lurking beneath our feet? To find out, we must seek genetic data from the earth itself.
Steelmaking coal mines in the Elk Valley of British Columbia are using microbes to help remove up to 99% of the selenium content from treated water, so it doesn’t end up in the local waterways. Credit: istockphoto
The Mining Microbiome Analytics Platform
To discover and implement these organisms, the Canadian government’s Digital Supercluster initiative has formed the cross-industry Mining Microbiome Analytics Platform (M-MAP). Teck, BGC Engineering, Rio Tinto, and Allonnia are participating, as well as the Centre for Excellence in Mining Innovation, Koonkie Canada, Genome BC, and the University of British Columbia.
The partnership’s goal is to extract DNA from 15,000 mine site water, rock, and soil samples, sequence it, and create an online platform for storing and analyzing the data. “M-MAP is trying to get ahead of the curve,” Rairdan explains. “As opposed to saying, ‘We know these organisms do this,’ we’re looking ahead and asking, ‘What organisms are out there and what are they doing?’ We don’t know exactly what we’re going to find, but we know that the data set doesn’t currently exist.”
Koonkie CEO Aria Hahn describes it this way: “At the end of every PhD defense, the classic question is, ‘If you had unlimited resources and time, what would you do?’ M-MAP is essentially a manifestation of those answers. We have the people, the volume of data, the access to resources, and the expertise to solve big problems and make big discoveries.”
*This has been an excerpt of an article originally published by Illumina. To read the full article, please visit Illumina.com.
