If the Trans Mountain pipeline expansion project is to proceed, meaningful consultation with First Nations will need to involve more Indigenous communities than just those who were involved in the court decision.

And that likely means a substantial delay to the project, according to Merle Alexander, an Indigenous resource lawyer with Miller Titerle and a member of the Ts'msyan Nation from Kitasoo on B.C.'s North Coast.

"I suspect, and my experience was, that every First Nation experienced the same failure of consultation," he said.

Alexander worked with First Nations who were involved in the court ruling and those who had signed impact benefit agreements.

"I've seen communities struggle with the complexity of the project from both sides," he told Stephen Quinn, the host of CBC's The Early Edition.

Any future consultation would have to include a "real and genuine sustained effort" with all the First Nations impacted by the project, not just those who appealed the Trans Mountain expansion in court, Alexander said.

"We're talking about a very substantial delay on the project."

The Federal Court of Appeal stopped the pipeline expansion in its tracks last week, ruling Ottawa failed to adequately consult with affected Indigenous communities.

Despite the ruling, the federal government says it's still committed to the controversial project Canada now owns.

A pipeline marker for the Trans Mountain pipeline as it passes by a playground near the Coldwater River and Coldwater Reserve in B.C. (CBC)

New negotiations

Khelsilem, who also goes by the name Dustin Rivers, is a spokesperson for the Squamish Nation.

"I'm curious to know ... how many First Nations are going to say, 'actually, we want out of what we signed before with Kinder Morgan, and we want a new negotiation with the federal government, so that given the court ruling, we actually want to be consulted properly as well,'" Khelsilem said.

The twinning of the 1,150 kilometre-long Trans Mountain pipeline will nearly triple its capacity to an estimated 890,000 barrels a day and increase traffic off B.C.s coast from approximately five tankers to 34 tankers a month. (CBC News)

The Squamish Nation was one of the Indigenous communities involved in the federal ruling.

"Through all the work that we did to participate, a lot of our concerns were not addressed, a lot of our questions weren't answered, and the final report didn't actually reflect anything that we had told them," Khelsilem said.

Khelsilem said questions and concerns about the impact of a potential spill in the inlet and details about the product being shipped across First Nation territory were not addressed.

"Going forward, a lot of those questions need to be answered," he said.

"There is a lot of information that needs to be ascertained."

With files from The Early Edition.

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