I would frame it as the initial responsibility of the operators who know their own particular operation, who know the loads that they carry, where their routing may be, the type of terrain, and what kinds of local risks there are along that terrain.
Then they get the feedback from municipalities along that route, for example, and the first responsibility is for the company to look at those questions and to look at the appropriate risk management approach. Then it is Transport Canada's responsibility to look at the sufficiency of that and Transport Canada can take action if more is required, but clearly, the initial responsibility is with the railway company.