As to exactly where the shunting is occurring, I think I'd defer to what BNSF is required to do in its operations, but I can tell you that there are proximity laws, and the Canadian Transportation Agency will deal with any noise or vibration complaints that result from the shunting activity, and has dealt with them. But in terms of where the shunting takes place, that would be something that railway operations would be responsible for.
On April 18th, 2016. See this statement in context.