My understanding is that the EPA rules grandfathered in all of them way back. Now refineries are are just being expanded every year at 15% or less to keep them under the old rules. No one can afford to meet the new rules, so they just work around them. Plus they have built new ones in the Caribbean without much regulations. We now import a lot gasoline instead of oil. Guessing Canada has serious rules too. 

The deal with Canada is that the refineries in Texas that were set up for that type oil used to get it from Venezuela and want to switch to Canada. Refineries have to be designed for a particular grade/type oil.

The oil with just go by rail now at a higher cost.