A North American environmental watchdog says it has found “scientifically valid evidence” that oilsands tailings ponds are contaminating groundwater sources.
The report was released today by the Commission for Environmental Cooperation, an agency tasked with implementing an environmental side accord to the North American free trade pact.
“Based on the scientific tools used today, the current literature shows that there is strong scientifically valid evidence of oilsands processed water seepage into near-field groundwater around tailings ponds when compared with the first peer-reviewed evidence published in 2009,” says the report.
Tailings ponds, such as the ones used by oilsands mining operations north of Fort McMurray, Alberta, collect by-products from oilsands mining operations — a mixture of water, sand, residual bitumen and other hydrocarbons that the industry calls “processed” water.
Many of these byproducts are toxic and environmentalists have long warned of the risks of leaks from tailings ponds, while the residual oil that covers the ponds can trap migratory birds.
These massive ponds are bordered by outer walls of dirt built to hold back the tailings water — which, as the report notes, “is an acutely toxic substance containing, among other things, naphthenic acids and heavy metals.”
For years it’s been unclear whether pollutants detected in waterways near oilsands operations came directly from plant operations or from bitumen already in the soil.
Although tailings ponds may be leaking into groundwater, the commission found there is less evidence to suggest it’s seeping into surface water sources like the Athabasca River, which runs adjacent to one of the oldest oilsands tailings ponds.
“The literature shows that there is no evidence of dissolved bitumen-derived organics (natural or anthropogenic) being detectable in any water samples, although a major challenge to spotting any seepage is dilution in a very large river,” the report states.
The Commission for Environmental Cooperation launched its probe of tailings ponds after environmental groups, including Environmental Defence Canada, filled a submission in 2017 that accused the federal government of failing to enforce the federal Fisheries Act by not prosecuting oilsands producers over the “alleged leaking of deleterious substances.”
The Commission for Environmental Cooperation cannot issue binding rulings, but instead its reports the facts it finds.
“To me, the evidence is really clear,” said Dale Marshall, a program manager for Environment Defence. “It tells us that the federal government is not upholding its responsibility to protect human health and the environment.”