As Canada's politicians threw blame around in the wake of TransCanada's cancellation of the Energy East pipeline, environmental groups hailed the decision, and called it a sign that the age of oil is coming to an end.
"The message from today's cancellation of TransCanada's proposed Energy East pipeline is loud and clear," the group Environmental Defence said in a statement.
"New tar sands pipelines don't make sense — economically or environmentally — in a world that is addressing climate change and moving away from fossil fuels."
Greenpeace took a similar tack, calling it "a great day for our water, climate and economy, and for Indigenous rights. The world is changing and the end of the age of oil is in sight."
TransCanada announced Thursday morning that, due to "changed circumstances," it won't be going forward with the Energy East and Eastern Mainline projects, which were to take 1.1 million barrels of oil per day from Alberta to ports on the east coast of Canada.
The company had announced last month it was suspending its efforts to get regulatory approval for the projects.
TransCanada did not specify reasons for the cancellation, but the industry has been rocked by persistently low oil prices in recent years, and Energy East faced a mass of political opposition, particularly in Quebec and from Indigenous groups.
But in a statement Thursday, the environmental group Sierra Club said the decision had to do with a tough new environmental review process at the National Energy Board (NEB).
In assessing a pipeline's environmental impact, the NEB had previously only considered the greenhouse gas emissions created by the construction of the pipeline itself.
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But in August the board announced it would now also count upstream and downstream emissions, meaning emissions at the site of production, and emissions created by the burning of the oil that passes through the pipelines. That decision was met with heavy criticism from the oil industry and its supporters, and applause from the climate activists who had pushed for the move.
Sierra Club gave some credit to climate groups for TransCanada's decision.
"TransCanada's statements indicate that new criteria Sierra Club members and thousands of Canadians pushed for ... shaped its decision to cancel the project," the group said in a statement.
Opposition Conservatives on the attack
The cancellation quickly became fodder for the Opposition Conservatives, who on Thursday laid the blame with the federal Liberals.
"Today is the result of the disastrous energy policies promoted by Justin Trudeau and his failure to champion the Canadian energy sector,'' deputy Conservative leader Lisa Raitt told a news conference on Parliament Hill.
She said new regulations on Canadian energy projects, brought in by the Liberals, have put Canadian energy companies at a competitive disadvantage.
"Justin Trudeau claims to support the middle class, but the truth is that the very people that the prime minister is claiming to help are the people most hurt by his misguided policies.''
Energy Minister Jim Carr dismissed Raitt's claims, arguing that TransCanada made a business decision influenced by low oil prices.
"I guess their role as the official Opposition is to try to score partisan political points,'' Carr said.
— With files from The Canadian Press and The Associated Press
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