Several police agencies already have cell phone tracking towers up and running, so it isn't like they don't have all of that data available to them. It would take a significant target for them to use chemical markers though I imagine. Of course the police will set up a 'whole operation' to bust a vendor though, didn't you already realize that? That is what the police do. They set up operations, to bust criminals. How many people visit a new drop box that has been identified as a box drugs were sent out of every week? If the vendor uses the same outgoing box for all shipped orders catching them will be trivial. How many people within sixty miles of Alice use Tor at all?