As a sailor who has floated most of the oceans at one point or another… I do not see any part of the west coast of Canada as safe for shipping at the Panamax size or higher, including Vancouver and Seattle. The waters are narrow, high latitude tides & currents, topography mountainous with an 8-month rainy season complicating the water flows. Heavy commercial and private traffic from small to large vessels, barge and log booms throughout.
For oil, the risk is simply too high.