First of all, the documents that explain how the tolls are going to be calculated are transparently available on the Canada Energy Regulator's website. I assume the government consulted them before making a decision on the pipeline purchase.
Secondly, you talk about tolls, so the tolls that will have to be paid by shippers. As we speak, we do not know what these tolls will be. The mechanics of their calculation are already available, but the final amounts have yet to be determined.
As long as this information is not available, we cannot assume that the fees will be too high or too low. The board of the Canada Energy Regulator will have to decide whether the tolls are just and reasonable when the case is presented to it.