In early February, Chief Allan Adam of the Athabasca Chipewyan First Nation in northern Alberta started fielding calls from community members after the provincial regulator revealed toxic wastewater had been leaking for months from a tailings pond at Imperial Oil's Kearl oil sands mine. Many in the community hunt and fish downstream of Canada's huge bitumen mines, and wanted to know if the game meat in their freezers was safe to eat.

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.

The federal government is providing bottled water and mental health services to First Nations struggling to deal with a spill from a tar sands tailings pond that went unreported for months in northern Alberta. “They’re devastated and their communities are devastated,” Indigenous Services Canada Minister Patty Hajdu said at a press conference in Ottawa on Monday. “They’re afraid that the water is contaminated.

A Dene Nation water summit being held this week has taken on new urgency as delegates deal with the fallout from Imperial Oil’s Kearl tailings spills. The northern Alberta oil sands mine continues to operate but has now been ordered by the federal government to take immediate action to stop months-long seepage of wastewater. A separate release of millions of litres of tailings at the same site was also revealed last month.