Tar sands oil that began leaking more than four months ago in northern Alberta is still bubbling to the earth’s surface, an environmental disaster that has prompted the Alberta government to intervene.
The government has ordered Canadian Natural Resources Ltd., the company in charge of the leaking Primrose tar sands operation, to drain two-thirds of a 131-acre lake on the property in an attempt to plug one fissure, located directly below the lake, which has been spilling tar sands oil into the lake over the four months. The order, according to CNRL, will allow the company to identify the exact location of the leak and attempt to halt it. The company’s plan to stop the other three leaks on the site is unknown, though CNRL says the seepage rate from all four leak sites has been reduced to fewer than 20 barrels a day.
The first of the four ongoing leaks at the Primrose site was reported May 20, and may well have started leaking long before that. As of September 11, the leaks have spilled more than 403,900 gallons — or about 9,617 barrels — of oily bitumen into the surrounding boreal forest and muskeg, the acidic, marshy soil found in the forest. In addition, 14,491 metric tons — 31,947,188 pounds — of “impacted soils” have been removed from the site, along with 515 cubic meters — 18,151 cubic feet — of oily vegetation. Two beavers, 49 birds, 105 amphibians and 46 small mammals have been killed as a result of the spill, according to the Alberta Energy Regulator.
Back in July, CNR attributed the cause of the four leaks to “mechanical failures of wellbores in the vicinity of the impacted areas,” but the Alberta Energy Regulator said in August that it was “far to early” to determine the cause of the event. CNRL said that the seepage was “now controlled to specific containment areas where it is effectively recovered as it reaches the surface” — basically, that the leaks were being monitored and the oil cleaned up, but the leaks weren’t being stopped.
Greenpeace Canada is calling on the Alberta government to put a moratorium on new tar sands development projects until the specific causes of leaks like those at the Primrose site were investigated, but in August, the Alberta Energy Regulator again said it was far too early to make decisions like that. So far, three investigations are planned around the leaks: Alberta’s department of Environment and Sustainable Resource Development, the government body in charge of monitoring the environmental impacts of the tar sands, is looking into the overall environmental impacts of the spill, including whether the spill impacted groundwater; the Alberta Energy Regulator investigating the cause of the leaks; and Environment Canada is looking into how the leaks impacted wildlife.
In 2009, there was a similar seepage incident at the same CNRL sites as two of the current leaks, the cause of which was never determined — the Alberta Energy Regulator’s investigation of the site was “largely inconclusive.”
“It’s crazy that it has come to this, and shows how hard it is to clean up tar sands incidents and the extreme nature of these spills,” Greenpeace Canada spokesman Mike Hudema said in a news release. “As the spill numbers and questions rack up, the Alberta government should, at a minimum, put a hold on approving new underground tar sands operations until we understand how these leaks are happening and if other sites could run into similar problems.”
Part of the reason why it’s so hard to determine cause of the leaks at the Primrose facility — and stop them — is that they occur underground. Instead of the open pit mining that tar sands operations are most famous for, the operation uses cyclic steam simulation, a process similar to fracking that pushes high-pressure steam underground, creating cracks in rock from which trapped oil can escape. CSS extraction is required to reach about 80 percent of Alberta’s tar sands. But the CSS projects aren’t the only ones to spill — on average, Alberta has had two crude oil spills per day for the last 37 years, according to data from the Energy Resources Conservation Board.