The Albian Sands tailings pond, located just north of the Fort McKay Indigenous reserve. At 1.5 trillion litres, the oil sands tailings ponds are the largest of their kind in the world. They house a liquid mix of toxic waste which contains dangerously high levels of mercury, arsenic, lead and benzene. Independent studies have found the the tailings ponds leak 11 million litres per day into the groundwater and Athabasca River.