A report released Thursday tracks the movement of heavy oil known as diluted bitumen through Puget Sound and raises questions about whether it is being transported safely.
Fred Felleman, a consultant for Friends of the Earth, who also serves on the Port of Seattle commission, has been tracking tugs and barges traveling between the Westridge Marine Terminal in Burnaby, British Columbia, and the U.S Oil refinery in Tacoma.
"What we found is there's a regular service about three times a month carrying this heavy oil, this diluted bitumen," Felleman told KIRO 7.
Diluted bitumen, also known as dilbit, can sink after it spills.
"Once this oil sinks, it's unrecoverable," Felleman said.
A U.S. Oil spokeswoman told KIRO 7 that the dilbit coming to Tacoma does not originate in Alberta's tar sands, but she would not say where it comes from.
A spokeswoman for Kinder Morgan, which operates the Trans Mountain Pipeline, told KIRO 7 on Thursday that everything in the pipeline comes from Alberta's oil sands.
She clarified Friday that the pipeline also carries conventional crude from Northern Alberta.
Canadian officials are considering allowing expansion of the pipeline, which would allow as many as 34 tankers per month to load in Burnaby, up from the current maximum of five per month.
Felleman said moving dilbit by tug and tow is worrisome because barges are harder to control than a ship.
In 1988, a barge broke loose off Grays Harbor, which state officials say led to a collision that spilled 231,000 gallons of fuel oil.
Spokesmen for the U.S. Coast Guard and Kinder Morgan said Thursday that dilbit has been shipped from the British Columbia terminal for 30 years without incident.
A Coast Guard spokesman pointed out that the barges are double-hulled, and said the risk of oil spills is well managed with navigational advisories and a network of spill responders.
Friends of the Earth has urged Washington lawmakers to start requiring escort tugs for oil barges to minimize the risk of a spill.
Similar requirements are in place in San Francisco Bay.
"If San Francisco Bay can do it, why can't we do it?" Felleman said.
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