A federal review panel's report on Enbridge's proposed Northern Gateway pipeline will be released Thursday afternoon in Calgary following more than a year of hearings in B.C. and Alberta.

The $6.5-billion pipeline would take bitumen from Alberta's oilsands to the B.C. coast for tanker export to Asia. But the controversial proposal has pitted Calgary-based Enbridge against environmental groups and several First Nations.

The pipeline is also a lightning rod in the debate over global climate change and has raised concerns about the effects an oil spill would have on environmentally sensitive areas along the B.C. coast.

The report will detail a joint review panel's recommendation on whether the project should be approved and the reasons behind it. The final decision, however, rests with the federal government, which has 180 days to decide.

The B.C. government had told the panel it did not support the pipeline as proposed, and more than 130 aboriginal bands signed a declaration against the project.

The panel can recommend conditions of approval for the project.

Ivan Giesbrecht, a spokesperson for the Northern Gateway project, said the hearings were the most thorough in history and he is confident the panel's decision will be based on solid science.

Politicians split on support

"We put a lot of hard work and effort into this process and we have confidence in the joint review panel, that they have reviewed it thoroughly and done it to the highest standards possible," Giesbrecht said.

Northern Gateway Hearings 20120110

Douglas Channel in Kitimat, B.C., is the proposed termination point for the Enbridge Northern Gateway pipeline. The 1,177-kilometre pipeline would deliver 520,000 barrels of petroleum a day from Edmonton through northern B.C. to the tanker terminal. (Darryl Dyck/Canadian Press)

Several new safety measures have been announced by federal Natural Resources Minister Joe Oliver since the hearings ended, and B.C. Premier Christy Clark has announced a truce with neighbouring Alberta in a dispute over her province's "fair share" of revenues from the project.

Alberta Premier Alison Redford said she hopes the panel endorses Enbridge's proposed pipeline as her province strives to diversify market access for the oilsands.

It would allow Canadian oil producers to reach the emerging markets of Asia and free them to sell outside what is currently their sole market in the American Midwest.

But Redford said approval would likely come with conditions.

NDP Leader Tom Mulcair said the controversial project should have been vetoed outright without wasting public money on a review.

Mulcair said the project is a non-starter because it would require supertanker traffic through British Columbia's Douglas Channel. He prefers the idea of a west-east pipeline — provided it is supported by a thorough, credible environmental assessment.

First Nations opposition a big hurdle

Even if the pipeline project is approved, he predicted vehement opposition from First Nations along the proposed route will eventually kill it.

"This is not going to be allowed to go through without a peep," Mulcair said, faulting the Conservative government for ignoring the rights and concerns of aboriginal communities.

"You can no longer impose these things from the top down. This is another era. You need social adhesion, you need to work with people. You can't just bark at them and say, 'This is going through.'"

Kimberly Sheardon of Ecojustice, which represented ForestEthics Advocacy, Living Oceans Society and Raincoast Conservation Foundation at the hearings, said the panel was given a narrow scope and some major concerns have yet to be addressed.

"We remain particularly concerned about the panel's failure to consider the upstream impacts of oilsands expansion this proposed pipeline would enable," she said in a statement.

"We are also concerned that the panel was not able to consider the recently released recovery strategy for the Pacific humpback whale, which shows a clear conflict between tanker traffic and the long-term survival and recovery of the whale population."

She pointed out the Northern Gateway decision will be the first since the federal Conservative government made sweeping changes to the laws governing environmental reviews, leaving the final decision in the hands of cabinet.

With files from CBC News