TORONTO – As long ago as 1556 with the publication of De Re Metallica by Georgiius Agricola, mining and mineral processing were known to be deleterious to water quality. It is a problem in search of an economic answer even today.
Among those seeking an low cost method of treatment is Margarete Kalin of Boojum Research. CMJ readers will be familiar with her work as it has appeared in our pages over the years. She is firmly of the belief that the best solution is not a water treatment plant that must operate eternally, but a passive treatment that harnesses the power of bacteria and other microscopic organisms. She has spent over 30 years researching the use of microbes to neutralize acidic effluents and to collect and precipitate metals out of water.
Kalin's latest approach is the bio-mineralization of metals in sediments. Her studies have successfully demonstrated introducing "good" microbes will prevent acidification. The practice is not yet mainstream, but as more is understood about the mechanism, it deserves to become widespread.
Studies done at the University of Ottawa showed for the first time that microbes cover minerals with an organic coating, a biofilm, and create a barrier to keep oxygen from reacting with sulphides in the minerals.
Work done in 2013 at the Biofilm Centre at the University of Duisburg-Essen conclusively showed that the addition of phosphate wastes promotes the growth biofilms by heterotrophs (organisms requiring organic compounds for their food source).
This year the Canadian Mining Innovation Council is thinking of acid drainage and looking at the Genome Canada Project. Examining microbes at their most basic level could aid in increasing their effectiveness. Kalin believes the Genome Canada Project could address questions, factors or conditions which control development of the biofilm and its long term stability.
"With the knowledge generated through Genomics … a cost effective and sustainable approach to mine waste and water management can be implemented," she says.
Readers wishing to know more about Kalin's work and/or support it should email her at [email protected].