Maegen Giltrow, lawyer for the Peace Valley Landowner Association, told the B.C. Supreme Court on Monday that the province erred by failing to consider all the recommendations put forward by a joint review panel assessing the dam's environmental impact.
The B.C. and federal governments granted environmental approval for the $8.8-billion project in October last year, signing off on nearly all of the 30 recommendations made by the provincial Environmental Assessment Office in its approval certificate.
But Giltrow said the panel actually made 50 recommendations, 20 of those were deemed to fall outside the scope of the review panel's mandate.
"If the panel has recommendations that go to the questions that were put toward it, the panel must include those recommendations and the minister must consider those recommendations," she said.
"The evidence is that the executive director (of the Environmental Assessment Office) advised the minister that these are not recommendations that the panel is allowed to make."
Responding to the court case Monday, Energy Minister Bill Bennett described the province's assessment process for Site C as "very thorough" and that he remained confident shovels would be in the ground by the summer.
Still, he admitted the possibility of an unexpected result.
"Any time an issue goes to court anything can happen," he said. "We'll just have to wait and see."
The B.C. cabinet gave final approval last December for the dam that would flood an estimated 5,500 hectares of land to create an 83-kilometre-long reservoir on the Peace River.
The courtroom was packed on Monday with more than 40 people in the public gallery. About half of those were landowners from the Peace Region who had travelled to Vancouver to watch the proceedings.
Gwen Johansson, mayor of the District of Hudson's Hope, said her community stands to be the most impacted by Site C, with the possibility of losing more than 1,800 hectares.
People have to have confidence that our decision-making processes are fair, just and transparent, said Johansson outside the courtroom on Monday.
"If people start to lose confidence in that then our democratic processes are at risk," she said, calling for the environmental assessment to be redone if the court finds it was lacking.
Poul Pedersen, who owns the closest property to the proposed dam site, said about half of his 65 hectares is in jeopardy.
BC Hydro plans to place an easement on a large section of his property because of the risk of erosion or "sluffing," he said.
While he would not be banned outright from farming, many of his buildings — including his home — fall within the proposed easement.
"If it's unstable you don't want to go to bed every night wondering if you're going to wake up in a reservoir," said Pedersen.
The case is the first of seven legal challenges against the provincial and federal governments from various groups opposed to Site C.
Opposition has dogged the long-range energy project over the decades, but that resistance has only heightened during the seven years it's been formally in the works.
The project is expected to produce 1,100 megawatts annually once completed by 2024, enough to power 450,000 homes.
Lawyers for the provincial government are expected to present in court on Tuesday.
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