Abstract

The oil sands in the Athabasca Basin in northeastern Alberta, Canada, are an important national resource whose development affects the economic well-being of all Canadians. However, this legacy comes with a significant environmental footprint. The extraction process to separate the mixture of sand, clay and bitumen produces large volumes of slurry wastes. This semi-liquid mixture is then stored in man-made dams, referred to as tailings ponds. The slurry’s components, namely the polycyclic aromatic hydrocarbons (PAHs), have been shown to be toxic to aquatic organisms and humans. We believe it is our responsibility as Canadians to reduce that footprint.

We have found that a variety of bacteria residing in the ponds are able to break down these contaminants. In particular, the breakdown of many PAHs generates a common intermediate – catechol – that is further degraded to Acetyl-CoA. Since these reactions naturally proceed at extremely slow rates, we plan to utilize the principle of metabolic channeling to increase the catechol breakdown efficiency. In turn, we will be able to accelerate the biodegradation of the contaminants in the tailings ponds.<p>