A decision to build a massive new oilsands mine north of Fort McMurray has been delayed. And that has Alberta's Opposition party worried the proponent might back out altogether.

The proposed $20.6-billion Frontier oilsands mine, if approved, would stretch over 292 square kilometres of boreal forest. That's an area roughly the size of Mississauga, Ont.

The proponent, Teck Resources Ltd., said the mine would employ 7,000 people during peak construction and 2,500 people during its operation.

Late Tuesday, Environment Canada announced in a press release it had granted the joint federal and provincial review panel an eight-month extension to decide whether or not to allow the project to go ahead.

This is the second review extension that has been granted. The panel was given 240 days to complete its environmental assessment as of Nov. 7. 

'Very concerned'

"I am very very concerned given the environment we are in," said Prasad Panda, the United Conservative Party MLA for Calgary-Foothills and the party's energy critic. "It takes forever to get anything built here."

Panda said he's particularly concerned as there is no other project as large as the Frontier mine under construction.

The timing is important, he said, because as construction wraps up on Suncor's Fort Hills project, many workers will be looking for new jobs.

Teck Resources spokesperson Chris Stannell declined CBC's request for an interview but said in an email the company is focused on "advancing" to a public hearing.

Complex project review

The panel reviewing the Frontier oilsands project asked both the federal and provincial governments for the extension in September.

Environment Canada had already granted a three-month extension on the decision after the 2016 Fort McMurray wildfire.

"The Frontier Oil Sands Mine Project application is complex," the panel's chair Alex Bolton wrote in a September letter posted to the Canadian Environmental Assessment Agency's website.

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Wood Buffalo National Park is under UNESCO’s spotlight. The United Nations body is determining whether the World Heritage Status deserves an “in danger” designation. (Mikisew Cree First Nation/ Submitted)

The panel said Teck made last-minute changes to the project description, which added many documents to the application.

The federal government also expanded the panel's mandate to consider the effects the project would have on Wood Buffalo National Park, a UNESCO World Heritage site.

Two Fort Chipewyan First Nations have also expressed concerns about the impact of the project on their lands.

Andrew Read, a senior analyst at the Pembina Institute, welcomed the extra time to review the mine proposal.

"I actually don't see a downside for delaying this project at this time during this review and making sure the information is fulsome," Read said.

"I see a lot of issues where there is gaps in information of how some of these issues are going to be addressed."

Read said there is no urgency to rush the project given the low price of oil and, therefore, lack of economic incentive to invest in large oilsands projects. 

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