EDMONTON — The B. C. government arrived at the Northern Gateway pipeline hearings in Edmonton with its environment minister, its former attorney general and a binderful of questions, only to get shut down for being out of bounds.

Elisabeth Graff, the lawyer for the province, was stopped moments into her cross-examination Thursday of pipeline builder Enbridge.

Graff was asking Northern Gateway president John Carruthers about the insurance for oil spill disasters when panel chairman Sheila Leggett intervened.

Leggett reminded Graff the Edmonton hearings are to focus on the economic impacts of the project and that disaster preparedness is being dealt with at upcoming hearings in B.C.

Graff said there had been consultation with Enbridge on the topics to be covered and that any overlap with other hearings would be minimal.

Not good enough, said Leggett.

"We have, as the panel, taken great pains to set these issues up in a way that we believed would be logical and would be in a manner so that we wouldn't have any overlap," said Leggett.

"That's an important piece for us as far as having an efficient and effective process."

The exchange happened late Thursday afternoon. By then, B.C. Environment Minister Terry Lake and former attorney general Geoff Plant had left the hearings to catch a flight home.

Graff is expected to resume Friday with questions on the corporate structure of the project.

Earlier Thursday, at a news conference held at the Vancouver Airport, B.C. Premier Christy Clark announced Plant had been hired to oversee the questions the province will ask Carruthers and six Enbridge (TSX:ENB) economists at the hearings in Alberta and the upcoming ones starting next month in B.C.

"He's going to be making sure that we get the answers to the questions that we need," said Clark.

"(He) is one of the finest legal minds in our country. He understands the environment, he understands the government, he understands politics, and our coastline. And the protection of our land base here in British Columbia is deeply important to Geoff."

Enbridge is seeking federal approval to build a $6-billion pipeline to ship oilsands crude from the Edmonton area to Kitimat on the B.C. coast, where it would then be shipped to markets in Asia.

In Edmonton, Lake told reporters he came in person to send a message that if there's a catastrophe, British Columbia residents will not be left holding the bag.

"Our questions will focus around liability insurance coverage, corporate structure and ensuring British Columbians wouldn't be left holding any kind of bill if in fact there was an adverse event," said Lake.

Plant said the corporate structure is of particular interest, given that Calgary-based Enbridge has created a separate entity to deal with the pipeline.

"I'm not worried that they're creating a shell (entity), but I don't want them to create a shell, and the people of British Columbia don't want to face the prospect of someone building a pipeline that isn't in a position where they can be held directly accountable for some harm caused."