Sorry but you are wrong.
https://www.thestar.com/news/canada/2016/11/29/liberals-approve-trans-mountain-line-3-pipeline-projects.html  
From the article "Finally, the Liberals rejected Enbridge’s controversial Northern Gateway proposal, which would have transported Alberta oil through the Great Bear Rainforest to Kitimat, B.C. The move was widely expected, with Trudeau saying for over a year that the rainforest is no place for an oil pipeline."
And if you listen to the link provided in the article, Trudeau says he rejected Gateway.