University of Calgary (UC) professors Howard Ceri and Raymond Turner have been working to develop a biofilm that will be able to absorb much of the toxic metal residue associated with tar sands’ tailing ponds, which store contaminated water from processing oil.
Turner, a biochemistry professor, explained that the technological discovery began as a side project, when the team decided to start researching biofilms naturally occurring in the tailings ponds ecosystem.
“What’s novel about what we’re doing,” Turner said, “is that we are growing these communities as biofilms.”
When explaining the benefit of using biofilms, Turner likens the communities to that of a city.
“We don’t have everyone in a city, every single organism, every human in the city, can do every job. We have the specialist; we have the plumber; we have the accountant; we have all these specialty organisms within a city community. Every individual species within the biofilm will only be able to degrade a certain amount of one kind of compound,” said Turner.
“As a community, in the biofilm, they are close together like we are in a city,” Turner added. “They can work together to get things done.”
Currently, remediation of tailings ponds occurs in a multi-step process.
“The tailings ponds have a lot of microbial activity. The problem is that, there would be metal contamination such that, with that metabolism, [degradation] happens quite slowly. If you can isolate the community organisms that can process all the organic pollutants as well as deal with the heavy metal components, you’d have a super community, if you will,” Turner explained.
This led Turner to collaborate with Ceri, who has spent much of his career looking at metal tolerance comparison between bacteria growing in a biofilm versus other forms of growth. Together they are trying to develop seed organism inoculants to treat the water layer that could be integrated with traditional water treatment.
The goal, Turner said, is “to create metal resistant bacteria that would lead to better organic, and maybe metal remediation, and be able to generate a water treatment process for remediation.”
Biofilms have been used in water treatment and bioremediation before. Water treatment plants in municipal facilities use some forms of biofilm in treating human waste. Other mining tailings have used biofilms for tailings, such as copper. But while a precedent has been set, biofilms are not widely used in the treatment of tailings.
There are many stakeholders who want to emphasize that the success of treating the tailing ponds doesn’t diminish the negative aspects associated with them.
Ramsey Hart, the Canada Program Coordinator of MiningWatch Canada, stated that while this discovery will improve the situation, it does not significantly alter the argument.
“If the water and sediments in the tar sands tailings ponds could be made environmentally benign then certainly that would improve the situation,” he said.
“However, there are still issues of the amount of land and energy the whole system is using, but storing millions of meters cubed of clean water and sediments would be better than the status quo,” Hart continued.
He also expressed reservations about the large-scale application. “I’m quite skeptical that this could be scaled up, but it’s kind of my job to be skeptical,” he said.
Turner and Ceri are nearly done their portion of the research. Turner said they will soon pass the research over to a team of engineers at the University of Alberta, who will begin testing the biofilms in a water treatment system.
“We gave the project six months to see if it would work,” Turner said in an interview with the Canadian University Press. “I never thought it would work in a lab… Where we are now is where we thought we would be in five years.”