The Tsleil-Waututh Nation conducted an in-depth review that spanned a year and encompassed six expert reports. The review found, among other things, that the fumes from spilled bitumen have the potential to make over 1 million people sick.
Rueben George, a band member who runs an initiative to oppose the pipeline, compared the expansion to an ancient legend about a two-headed serpent that blocked Burrard Inlet.
"Our ancestors had to slay that dragon. So we've always been protectors of our lands and our waters here," he told a cheering crowd gathered on a North Vancouver shore on Tuesday.
"Now we're facing another long dragon that needs to be slain. That's the Kinder Morgan pipeline."
Kinder Morgan hopes to triple its bitumen-carrying capacity to 890,000 barrels a day by laying almost 1,000 kilometres of new pipe near the existing pipeline that runs from Alberta to Burnaby, B.C.
The Tsleil-Waututh's traditional territory includes Burrard Inlet, where tanker traffic is expected to increase seven-fold if the expansion is approved.
The National Energy Board is currently reviewing Trans Mountain and interveners are releasing critical reports ahead of a deadline Wednesday to submit evidence. The board will make a recommendation in January 2016 to the federal government, which will issue a final decision.
Spokeswoman Ali Hounsell said in a statement that Kinder Morgan "deeply respects" aboriginal rights and will fully respond to the nation's report. She said the company has consulted with about 133 First Nations and has tried to have multiple discussions with the Tsleil-Waututh.
"With the release of this new report, we once again invite the Tsleil-Waututh First Nation to come to the table," she said.
The report said that spilled oil or bitumen seriously threatens all components of the nation's subsistence economy, especially salmon, herring, clams and birds. A major spill could kill up to 5,000 birds, strand 90 per cent of the oil on the nation's beaches and foul up to 25 kilometres of shoreline, it found.
But the pipeline's impacts on the nation's culture could be even larger than the effects on the environment, the report concluded.
George said his people have a spiritual and historical connection to the water that once provided 90 per cent of their diet, so they must protect it.
"What we know is that we can't put a price on the sacred. We can't put a price on our children. We can't put a price on who we are," he said.
Scott Smith, a lawyer for the nation, said the federal government is legally obligated to recognize the Tsleil-Waututh's inherent law and jurisdiction. He warned the government will face lawsuits if it approves the project without the nation's consent.
Four law professors, including Gordon Christie of the University of B.C., released a statement Tuesday that said the nation's decision opposing the pipeline expansion creates "uncertainty and legal risk" for the Kinder Morgan proposal.
The Tsleil-Waututh also launched a legal challenge of the energy board's review of Trans Mountain last year, arguing against what it called a false and unlawful process.
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