Last week, crude oil started flowing through a newly expanded pipeline that stretches more than 600 miles from the tar sands of Canada’s Alberta province to an export terminal near Vancouver in British Columbia. The Canadian government spent $25 billion and more than four years to complete construction on the Trans Mountain Pipeline expansion which will triple its capacity to ship nearly a million barrels of oil a day. But the project has also raised concerns about the threat of oil spills south of the border, and the harm to endangered marine mammals from increasing tanker activity moving through the Salish Sea to customers in Asia. Tom Banse, OPB’s former Olympia correspondent, joins us to share his recent reporting on this story.