VANCOUVER, B.C. ─ Diluted bitumen won’t exactly sink most of the time but it won’t exactly float all of the time, either, according to new evidence filed with the Joint Review Panel hearing the Enbridge Northern Gateway application in Prince Rupert. In cross-examination by Ecojustice counsel Karen Campbell today, Enbridge consultants admitted that tank test evidence filed this week found dilbit did submerge beneath the surface of the water, although none was found to have sunk to the bottom of the tank.

The new evidence was filed this week in response to a motion brought by Campbell on Wednesday, on behalf of a coalition of intervenors including Living Oceans, Raincoast Conservation Foundation and Forest Ethics. Campbell argued that witnesses had referred to evidence not on the record that they claimed would show that dilbit spilled from tankers at sea would not sink or submerge, making it hard to recover. The panel ruled that the evidence must be filed and has allowed all intervenors to seek leave to file formal response evidence at a later date.

Living Oceans has maintained that diluted bitumen, with its high content of heavy asphaltenes, was likely to behave like the heaviest of heavy oils when spilled in the ocean.

“Heavy oils often submerge beneath the surface water, making it extremely difficult to track and contain spills, and harder still to recover spilled oil,” said Karen Wristen, Executive Director of Living Oceans.

In cross-examination today, Enbridge admitted that the dilbit used in the consultant’s tank tests did, in fact, submerge. The coalition’s goal in cross examining Enbridge on this issue was to highlight the dearth of information on how dilbit and other heavy oil products could behave in the North Coast ocean environment. 

“We know that dilbit sank at the Enbridge pipeline spill in Kalamazoo and this real world experience provides a much clearer indication of what we’d face on the North Coast than a tank test in Ottawa,” said Brian Falconer, Director of Marine Operations for Raincoast Conservation.

The evidence is vital to a finding that the Panel has to make regarding the potential for adverse environmental effects to be caused by Enbridge’s proposal to ship diluted bitumen in tankers from a terminal at Kitimat, B.C.

“Clearly, spilled oil will have adverse environmental effects,” said Wristen. “The question then becomes, can those effects be mitigated? Our contention has always been that they cannot; that as much as 90 percent of a spill is often unrecoverable.” 

Evidence filed from studies of the Exxon Valdez oil spill of 1989 indicates that there is still an estimated 80,000 litres of heavy oil in the subtidal zone of Cordova Bay, where the herring fishery has never recovered.