A recent string of leaks from tailings ponds at oil sands operations upstream has once again drawn attention to the profound transformation Canada’s largest industry has had on the region – and the distrust that comes with it. In May, Calgary-based Imperial Oil notified Alberta’s energy regulator it had discovered discoloured water near its Kearl oil sands project. The regulator soon concluded the water had come from tailings ponds where the company stored the toxic sludge-like byproducts of bitumen mining. Environmental samples showed high levels of several toxic contaminants, including arsenic, iron, sulphate and hydrocarbon – all of which exceeded provincial guidelines.