If a tanker runs aground in southern B.C.'s coastal waters, where will the oil end up? That's the question conservation groups are trying to answer with a research project launched yesterday.

High school students from the Tsleil-Waututh First Nation, along with several reporters, were invited aboard the Raincoast Conservation Foundation's research boat Achiever in Vancouver's English Bay Thursday afternoon for the release of the first batch of 1,000 yellow plywood 'drift cards' that will be dropped along tankers' route to the open ocean.

Key locations between English Bay and Victoria's Race Rocks were chosen based on what Raincoast and the Georgia Strait Alliance -- the two groups behind the initiative -- say are danger zones for tankers carrying oil.

The cards are marked with information about the project, and an individual number and letter to indicate its starting point. Members of the public who find these cards on shore are asked to report back to the organizations, giving researchers an idea of how oil would be dispersed in the case of a spill.

The drift card method is one employed by the National Oceanic and Atmosphere Administration to simulate the trajectory of oil and other pollutants.

The impetus for this initiative is a Kinder Morgan proposal to increase capacity of its Trans Mountain pipeline, which carries Alberta crude to terminals in Vancouver's Burrard Inlet, where tankers fill up and head west. Kinder Morgran wants to twin this pipeline to move an additional quarter-million barrels a day -- and more product means more tankers.

However, this isn't conventional oil; it's diluted bitumen. This unrefined tar is treated with chemicals to make it possible to move via pipeline, and when it hits water -- as evidenced by a devastating recent spill in Kalamazoo, Michigan -- it behaves in an entirely different way. The bitumen -- the heavy tar -- sinks, while the lighter chemicals used to dilute the tar off-gas into the atmosphere.

It's a problem that Raincoast biologist Ross Dixon is well aware of. Even in the case of a diluted bitumen spill, where some of the substance will sink, it's important to know how the wind, ocean and surface currents are moving.

"What will a spill trajectory look like?" he said. "With this, we hope to outline a number of different scenarios."

More important, he said, is getting this information into the hands of the public.

Raincoast is offering a prize -- the coffee table book Canada's Raincoast at Risk' -- to whomever finds the first drift card. Anyone who finds a drift card is asked to report it at www.salishseaspillmap.org, where they can find more information about the project.

Colleen Kimmett is an editor at The Tyee.