Testing the waters

“Not only do all human beings need water to survive,” says researcher Brent Wootton, “all life needs it.”

As the director and senior scientist of the Centre for Alternative Wastewater Treatment (CAWT) at Fleming College in Lindsay, Ont., he clearly sees the potential benefits of his research. “It’s incredibly rewarding to know that working on applied solutions for improving water quality can have such an important impact on the lives of people around the planet and on the planet itself.”

Since its inception in 2002, the CAWT has become a hub for constructed wetland and alternative waste-water treatment expertise and applied research. And now, funding from the Canada Foundation for Innovation (CFI) will allow the centre to renovate its facilities and upgrade its equipment to help the facility expand its work into areas such as industrial effluents.

Enhanced infrastructure will enable more applied research and development for both private and public partners, including investigating biologically based treatment systems for the removal of toxic trace elements, particularly in the mining sector.

“Water contaminated with trace elements is a problem around the world, especially in industrial settings,” says Wootton. “Many trace elements are toxic to organisms at very low concentrations, and it is difficult to remove or immobilize contaminants that are highly soluble.”

Wootton is looking to bacteria-based treatment systems as an environmentally sound approach to removing these trace elements from waste water. While most such systems are used to break down natural waste such as sewage, the bioreactors Wootton studies use bacteria to treat heavy metals. “The bugs can’t destroy the metals; they simply make them insoluble,” he explains. “By doing so, the metals precipitate out as a solid and can then be captured and recycled or disposed of properly.”

A number of factors affect the efficacy of this method. “Detailed knowledge of the types of bacteria, their interdependency and the requirements of system design to optimize both summer and winter performance is critical to expanding the usefulness of these systems,” says Wootton. “By examining, defining and determining the processes that take place in an operating bioreactor, we hope to improve the efficiency of metal removal as well as long-term performance reliability.”

An added benefit is that these systems are cost-effective compared with traditional dig-and-dump methods and lime-based effluent treatment for metal contamination. “They require less maintenance and are very well accepted by communities,” says Wootton. He’s confident that as the CAWT expands its knowledge of these systems, it will lead to improvements, eventual commercialization and adoption on a large scale.

While the CAWT already hosts a range of experiments on biological treatment systems and has, as a result, established partnerships with 40 companies, more research is needed to commercialize the technology. “A select number of these companies from the mining industry and related sectors are eager to partner with Fleming to pursue this research,” says Wootton.

The need for technological advances in water treatment is critical for Canada’s mining industry which, according to the Canadian Mineral Industry Federation, contributed $32 billion to the country’s GDP in 2009 and employed 306,000 workers. An estimated 1,000 Canadian exploration companies are also active in more than 100 countries around the world.

In Ontario alone, there are more than 5,700 known abandoned mine sites. Of these, 4,000 sites could be hazardous to public health and safety and the environment. It has been estimated that it could cost approximately $500 million to properly rehabilitate all of these mine sites.

“Mining is a rapidly growing sector with equally expanding environmental constraints,” says Wootton. “Developing a technology that is effective in the diverse climatic and geophysical conditions found in Canada will result in a technology that can be exported to virtually any jurisdiction in the world.”

1Government of Ontario, Ministry of Northern Development and Mines http://www.mndm.gov.on.ca/mines/mg/abanmin/default_e.asp