When Prime Minister Justin Trudeau announced approval of Kinder Morgan's Trans Mountain pipeline project, he framed it as a decision based on science.

Perhaps he didn't check his inbox before making that pronouncement, because the pipeline decision seems not to have taken into account concerns expressed by many of Canada's young scientists about the flawed environmental-assessment process in this country.

"If I thought this project was unsafe for the B.C. coast, I would reject it," Mr. Trudeau said last week in declaring the controversial pipeline is going ahead. "This is a decision based on rigorous debate, on science and on evidence. We have not been and will not be swayed by political arguments– be they local, regional or national."

Story continues below advertisement

In taking office, Mr. Trudeau promised he would be guided by just such principles.

"We are a government that believes in science – and a government that believes that good scientific knowledge should inform decision-making," he wrote in his mandate letter to Minister of Science Kirsty Duncan.

The problem is, the scientific process the government relied on in making the Trans Mountain decision is suspect. That's not just according to environmental critics of the project. In a letter to Mr. Trudeau on Nov. 15, more than 1,700 scientists early in their careers expressed doubts about the process by which major projects are assessed.

"We are concerned that current environmental assessments and regulatory decision-making processes lack scientific rigour, with significant consequences for the health and environment of all Canadians," they wrote.

Story continues below advertisement

"As the next generation of Canadian scientists, we are professionally and personally affected by such decisions, especially regarding large-scale and long-term projects. Not only might our expertise be required to mitigate problems, but we have longer to live with the impacts, including a planet profoundly affected by climate change."

The scientists did not take issue with any specific projects. But they wrote the letter shortly after the government had approved the controversial, $11.4-billion Pacific Northwest LNG project (which will impact important salmon habitat at the mouth of the Skeena River) and they wrote it knowing Ottawa was contemplating three pipelines: Enbridge's Northern Gateway and Line 3 proposals, and Kinder Morgan's Trans Mountain.

Clearly they were trying to alert the government to grave concerns within the scientific community about the way big projects were being reviewed.

Mr. Trudeau forged ahead, however, rejecting Northern Gateway but approving both Line 3 and Trans Mountain while claiming the decisions were "anchored in science not rhetoric."

Story continues below advertisement

B.C. Green Party Leader Andrew Weaver, a noted climate-change scientist and the MLA for a Vancouver Island riding that has waterfront along the oil-tanker route, has taken issue with that in relation to Trans Mountain, which crosses B.C., reaching tidewater in Burnaby and increasing tanker traffic from 60 vessels a year to 408.

"As a scientist, I can say unequivocally that we remain completely and utterly unprepared for a major oil spill," he said.

Mr. Weaver also complained that "approval of this project is completely contradictory to this government's rhetoric at the Paris climate talks."

Reflecting the concerns expressed by his young scientific colleagues, he also said that "the ways in which projects are receiving approval no longer meets the expectation of Canadians."

Story continues below advertisement

The young scientists who wrote to Mr. Trudeau made five recommendations "to help rebuild public trust in robust, open and fair decision-making."

They say that environmental impacts should only be assessed by parties at arms-length from proponents; that cumulative environmental effects need to be considered; that all parties should disclose any potential conflicts of interest and that explicit criteria must be developed to "ensure that decisions are based on science, facts and evidence."

In its hearings, the NEB did not meet those standards, and instead relied largely on science done by the pipeline proponents. That's the science Mr. Trudeau endorsed when he approved Trans Mountain.

"Since limited or biased science will not fully reflect the benefits and risks of a project, it cannot accurately inform decision-making," Canada's young scientists state in their letter. Another way of putting that is garbage in, garbage out – a computer-programming term that means inputting incomplete information leads to faulty decisions.