NEB panel members Kenneth Vollman, left, David Hamilton and Gaeton Caron leave the Midnight Sun Recreation Complex after a day of hearings wrapped up earlier this week. (Allison Devereaux/CBC)The National Energy Board must now decide whether to approve a natural gas pipeline through the Northwest Territories' Mackenzie Valley, after it wrapped up its final hearings Thursday in Inuvik, N.W.T.

Members of the independent federal agency, which regulates parts of Canada's energy industries, have until September to decide if the 1,200-kilometre Mackenzie Valley pipeline should be built, and under what conditions.

Since 2006, the NEB has been holding hearings into the $16.2-billion pipeline, spearheaded by a consortium of companies led by Calgary-based Imperial Oil.

"On the 25th of January, 2006, in this room in Inuvik, we welcomed you to the opening session of the National Energy Board hearing for the Mackenzie Gas Project. We now bring this hearing to an end," NEB panel chairman Kenneth Vollman said Thursday at the Midnight Sun Recreation Complex.

The board had spent the last two weeks in Yellowknife and Inuvik, hearing final arguments from pipeline supporters, opponents, critics and the project proponents themselves.

On Thursday, the board heard the last final argument from Imperial Oil's lawyer, Don Davies, who congratulated the NEB for giving the chance to participate and keeping the hearings efficient.

However, Davies was less complimentary about other regulatory processes in the North.

"How long will it take for northern regulators to review the project permit applications, for which approvals is required?" Davies told the board.

"If we were to use the Dehcho geotechnical program application as a precedent, the answer would be seven years and counting."

If approved, the Mackenzie Valley pipeline would be built through the Northwest Territories' Mackenzie Valley, from the Beaufort Sea to a hub in northern Alberta.

Other members of Imperial Oil's consortium are ExxonMobil Corp., ConocoPhillips, Royal Dutch Shell PLC and the Aboriginal Pipeline Group.

Managing uncertainty

People in Inuvik, N.W.T., listen to the National Energy Board's final hearings this week. (Allison Devereaux/CBC)Davies said there is uncertainty in the consortium's talks with the federal government about getting financial breaks for the project.

He argued that a project permit from the National Energy Board — if granted — should not expire in December 2013, which is the current NEB proposal.

Many interveners, including the N.W.T. government and the Inuvialuit Regional Corp., have called on the board to keep the permit's sunset clause at 2013.

But Davies said Imperial Oil and its partners have good reasons for wanting until December 2016 to decide whether or not to start building.

"They are requesting that date in order to reasonably manage uncertainty, and we continue to believe that the request is reasonable, notwithstanding the collective frustrations of all of us," he said.

That sunset clause, along with many more conditions of an NEB permit, are now in the hands of Vollman and fellow panellists Gaeton Caron and David Hamilton.

"Now we have our work cut out for us," Vollman said. "You can expect to receive our decision, with reasons, in September 2010."