A pipeline rupture under the Red Deer River just over two years ago carries important implications across the oil and gas industry, including for the proposed Keystone and Northern Gateway pipeline projects, says a river researcher from the University of Lethbridge.
Professor Stewart Rood and his research team were given a unique opportunity to analyze results from the cleanup after flood debris ruptured a pipeline carrying light sour crude under the Red Deer River, just downstream from Sundre.
The spill was discovered on June 7, 2012, at the river’s confluence with Jackson Creek. There was a pool of crude at the mouth of the creek, so there was an assumption that the spilled had occurred there, Rood said. The pipeline actually broke further upstream, near the Sundre sewer treatment plant, he said.
The result was the release of about 450,000 litres of crude into the river, upstream of the Gleniffer reservoir.
More oil would have been spilled had the pipeline been flowing at the time, said Rood.
Rood said he is “astounded” that there has not been more research into spill cleanups, given that pipelines have been shipping oil for more than 50 years. Better research would help governments and oil companies respond more appropriately to pipeline spills, he said.
There is less chance of a rupture if the pipeline is placed well below the riverbed, out of danger from flooding action, said Rood.
When rolling rocks and flood debris do cause a break, the pipelines release a mix of hydrocarbons that react in various ways to natural processes, he said.
Teams responding immediately after a pipeline rupture have a duty to contain the spill, mop up as much of the oil as possible and scare off birds and animals that attempt to enter the contaminated area, said Rood.
However, the aggressive cleanups that follow an initial response have often caused more harm than good, including the cleanup after the 2012 break, he said.
Pipelines under rivers tend to break during spring flooding, when native trees and shrubs along the flood plain are in full leaf and growing rapidly, said Rood.
“The key plants, the willows and the cottonwoods … are really good at what’s called phytoremediation. In fact, these things are deliberately planted in some contamination sites and part of the reason is that they use a lot of water, so they go through ground water and in so doing they’re able to remove contaminants and the like,” he said.
“Rather than mowing down the willows and cottonwoods that have been contacted with the oil from the rupture … in areas that are thinly coated, I think you’re better off leaving them.”
Rood and his crew documented considerable progress at three designated sites along the banks of the Red Deer River, including evaporation of volatile hydrocarbons and suffocation of the leaves that were coated in crude and eventually fell to the ground.
As time progressed, the tarry substance that covered the trees and rocks on the floodplain dried up and, where there was moisture present, microbes and bacteria completed the breakdown of the remaining material.
The trees that had been in the flood plain grew new leaves and suffered no long-term damage, said Rood. The impact on them was no worse than what they would have suffered from an infestation of tent caterpillars, he said.
On the other hand, where costly and aggressive cleanup has been performed, such as bulldozing river banks and removing contaminated material, there have been devastating consequences including the introduction of invasive plants like as reed canary grass.
At one time, the United States Environmental Protection Agency recommended bulldozing and removal of all contaminants from a spill site, with devastating results, he said.
Funding for the Red Deer River research project included $67,200 from fines totalling $1.3 million levied against the pipeline company, Plains Midstream Canada, after it pleaded guilty to charges laid under Alberta’s Environmental Protection and Enhancement Act in connection with the Sundre break, as well as a similar spill in the Peace River region.
Additional money from the fines went to the Alberta Conservation Association for projects and to the federal government’s Environmental Damage Fund, for projects within the affected watersheds.