The Canadian Tar Sands hold a huge portion of the World’s proven oil reserves. The technology to cost effectively mine and process bitumen into crude oil continues to improve.
Environmentalists absolutely hate Canadian tar sands crude. Most of the objections are to strip mining in the pristine frozen north and the CO2 emissions from mining and processing, but the environmentalists cannot stop this. So they have focused on obstructing the cost effective transportation of tar sands oil to make tar sands oil uneconomic.
They talk as if tar sands crude is the most toxic and dangerous substance on earth and they fight every effort to transport it, particularly cost effective pipelines.
So forget about building tar sands crude pipelines. They are politically toxic. Refine the oil near its source in Alberta into generic higher value products: gasoline, jet fuel, heating oil and diesel. Then build pipelines to transport those relatively clean and well understood products.