"British Columbia has the power to grant or withhold 60 permits," she told students Tuesday at the University of Calgary's School of Public Policy.
"British Columbia's power would be required to power up the pipeline from B.C. Hydro, a Crown corporation. There's a whole number of things the British Columbia government could do and certainly if this project was forced through without meeting the five conditions, it wouldn't be just the British Columbia government that would be in court. It would be every First Nation across the line."
Clark's government has set out five conditions under which B.C. would allow projects like Northern Gateway and Kinder Morgan's Trans Mountain expansion to go ahead.
Three have to do with the environment, one with aboriginal consultation and one — the most contentious — with getting a "fair share" of the economic benefits.
This isn't the first time the B.C. government has tried to make this point.
In July, B.C. Environment Minister Terry Lake warned that even if the National Energy Board recommends approval of Enbridge's $6 billion project, there are scores of provincial permits that must be obtained. Clark has also spoken before about how the pipeline would require power from B.C. Hydro.
Later Thursday, Clark qualified her remarks to reporters.
"To me all the speculation about how British Columbia would stop it is kind of silly because the thing is if British Columbia doesn't give its consent to this, there is no way the federal government or anyone else in the country is going to be able to force it through. It just won't happen."
Clark told the students that it is important for Canada to get its resources to market; the Indian middle class is growing fast and China is rapidly urbanizing.
"Canada needs to be a part of that."
But she said moving thick oilsands bitumen product via the pipeline poses a big environmental risk — riskier than lumber, natural gas or other products — and needs to be handled with extreme care.
Citing a study filed to the panel currently reviewing the contentious project, Clark said B.C. stands to bear all of the risk and only eight per cent of the financial rewards.
"If you were in business, would you take that deal?" Clark asked. "And the answer for me is quite simply, I will not."
Clark said she feels like the repairman in old Maytag commercials, waiting for the phone to ring with a proposal from pipeline proponents she can accept.
Clark made a "courtesy call" to her Alberta counterpart Alison Redford on Monday, a meeting which both women described as "frosty" and short on progress. Redford was adamant that Alberta will not share resource royalties with B.C.
Clark has no plans to discuss B.C.'s demands with industry.
"It's not a British Columbia project. I think that we in British Columbia have done our bit to set out a clear path for this to move ahead or not," Clark told reporters.
"I think the people who have the most vital interest in having it go ahead are the ones that are going to have to decide to move it forward. If they don't, I think the odds of it happening are really slim."
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