Construction will proceed on the Trans Mountain pipeline expansion this month, despite the Federal Court of Appeal agreeing to hear six challenges to the project.

Canadian Association of Petroleum Producers CEO Tim McMillan said in an emailed statement Wednesday that while the oil lobby group is disappointed with the court's decision to grant leave for appeal, it's just a setback.

"The [Trans Mountain pipeline expansion] has already undergone a lengthy, thorough and extensive regulatory review process, including extensive consultation with all stakeholders. It has been deemed to be in the best interests of all Canadians," McMillan said. "Despite this setback, CAPP fully expects construction on the TMEP to begin in September."

A spokesperson from Trans Mountain Corp. echoed that statement, saying that the Crown corporation plans to move forward with planning and construction.

"Trans Mountain is confident in the certificates and approvals obtained to date and we look forward to building and operating this project in a manner that minimizes impacts to the environment and provides benefits to all Canadians," an emailed statement from the company read.

"The applications are challenging the decisions made by the Canada Energy Regulator and the federal government, but do not in and of themselves negate the pre-existing approvals provided by those governmental authorities until and unless the court rules otherwise."

Project twice approved

The federal Liberal cabinet has twice approved the project, which is set to be finished by mid-2022.

That timeline could be in jeopardy if the appeals from B.C-based Indigenous groups are successful again at convincing the court to quash those approvals and nullify construction permits.

Alberta Energy Minister Sonya Savage says the project is desperately needed.

"Of course we're disappointed," she said Wednesday. "We need construction to start now. We need shovels in the ground. We don't want to lose a construction season."

Alberta Energy Minister Sonya Savage said she was disappointed by the Federal Court's decision to hear six appeals of the federal government's approval of the Trans Mountain pipeline expansion project. (CBC)

But Savage said she did see "good news" in the judgment — that another six requests for appeal were denied.

"The court just said you can't continuously litigate and litigate," she said.

"As it stands right now, the project is still approved."

In an unusual move, the Federal Court posted its reason for agreeing to hear the appeals — stating Indigenous groups have raised serious concerns about how the government re-did its consultation process.

The court has ordered challenges to proceed on an expedited basis.

Situation is 'déjà vu,' says legal expert

David Wright, an assistant law professor with the University of Calgary, said it's difficult to predict what kind of delays may ensue based on the court's decision.

"This is a little bit of déjà vu. This time just over a year ago there was very preliminary construction happening despite the legal challenges … you'll probably see some level of construction continue throughout this litigation. But the fatal risk to the project will be alive throughout that," he said.

Wright said the timeline for these appeals could be as short as three to four months.

Trans Mountain has said it expects 4,200 workers to be employed along the pipeline corridor by late 2019.

If completed, the pipeline expansion will carry nearly a million barrels of oil per day from Alberta to the B.C. coast.