PRINCE RUPERT, B.C. - The proponents of the Northern Gateway pipeline have made many promises as they seek approval of their multibillion-dollar pipeline, but there is no guarantee those commitments will endure, says a lawyer representing environmental groups.

Karen Campbell, who represents ForestEthics, Raincoast Conservation and Living Oceans, asked a panel of company experts at federal review hearings Friday if promises of a marine spill response and wildlife recovery studies will survive the 50-year life of the project.

"Can you ensure that the commitments that you've made over and above the regulatory requirements would be adhered to by any future owner of this pipeline?" Campbell asked.

"We anticipate that the project would be subject to conditions from the joint review panel, and that any owner would have to respect those conditions that are imposed upon the project," replied John Carruthers, president of Northern Gateway Pipelines and one of a dozen company experts answering questions under oath this week.

Asked if the company would take steps to make those commitments legal, Northern Gateway lawyer Dennis Langen objected.

"I don't think it's fair to get into legal issues well into the future with these witnesses," he said.

Campbell questioned the science Northern Gateway has presented to the panel, including their own study that found diluted bitumen — the type of heavy oil that will flow through the pipeline — will not sink in the event of a tanker spill.

She also questioned their assessments of the effects of oil on killer whales and the ability to clean-up a spill in the wind and wave conditions found in Hecate Strait in winter.

"We are trying to understand their science, and we're trying to really hold them to task," Campbell said. "When they say their science is robust ... we'd like to make sure that it's robust, and so far we've seen some gaps."

Panel members were adamant that preventing an oil spill is the main aspect of their plan, a goal shared by shipping companies.

"None of these shippers want to lose their cargo," said Ed Owens, a consultant from Polaris Applied Science, an oil spill response company based in Washington state. "It costs them a lot of money."

The hearings — quasi-judicial proceedings dominated by lawyers and scientists — have been a struggle for members of the public and citizen interveners such as Douglas Channel Watch, a grassroots group from the Kitimat area.

Lawyers for the Council of the Haida Nation appealed this week to Northern Gateway's experts to respond in language that elders listening to a live broadcast might be able to understand.

The panel spent much of the week discussing such topics as the chemical properties of asphaltene, the specific gravity of diluted bitumen, emulsion viscosity and stochastic modelling.

"This is difficult material," Campbell told the panel. "I have been trying to make sense of these things."

Outside the hearings, the debate has taken on a more personal note.

On Friday, Murray Minchin, a member of Douglas Channel Watch, published an open letter to Alberta concerning claims the province is losing out on billions because of stalled pipeline projects.

"Why is Alberta so cash-strapped that you have to squander what you have so quickly, without adding value?" he wrote in a letter published in several B.C. newspapers and in an abridged form in the Edmonton Journal.

"Where did the money go, and why did the companies get away with paying so little?"

Minchin suggested there will be construction blockades if the project is approved.

"We aren't willing to risk the things we value most to bail your province out of its colossal mismanagement of the tar sands," Minchin wrote.

The review panel hearings will resume in Prince Rupert later this month, when they will continue hearing testimony on Northern Gateway's marine response plan.

What became clear in the past week is that, while Northern Gateway has committed to having in place an emergency response regime in the event of a marine spill, they do not yet have that plan.

The federal review panel has until the end of the year to produce a report and recommendations for the federal government.

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