Though Alberta’s government has proclaimed it false, a new report from issued by Environmental Defence claims that over four billion litres of contaminated tailings water enters the groundwater each year as a result of oil sands operations. New projects, it adds, could expand this number to over 25 billion litres within a decade.
The report, 11 Million Litres a Day: The Tar Sands’ Leaking Legacy, uses industry data to arrive at an estimate of tar sands tailings ponds leakage into the environment.
Four billion litres would fill the Toronto Rogers Centre (formerly the SkyDome) two and a half times. 25 billion litres would fill it 16 times.
“This massive leakage from toxic tailings ponds are yet another reason why tar sands oil is dirty oil,” said Matt Price, program manager, Environmental Defence.
Tailings ponds are known to contain dozens of toxic contaminants like heavy metals, polycyclic aromatic hydrocarbons (PAHs) and naphthenic acids. Naphthenic acids in particular break down very slowly and therefore pose a long-term threat to the groundwater of the region. The tailings ponds sit upriver from the Peace-Athabasca Delta, one of the world’s largest inland freshwater deltas and home to Fort Chipewyan where residents already have serious concerns about pollution and their health.
Tailings ponds are built on bare ground with walls made out of earthen materials. Companies deploy measures to capture some of the leakage from the ponds, but these measures are imperfect. Company applications for new projects admit that leakage is lost to the groundwater, and these applications were used to arrive at the overall leakage rate.