I also be leave that there should be one trash can to rule them all. After a bit more thinking, I do understand the need to have a separate trash for each of the types of items you may wish to delete. But there should also be a central place to see all item in the trash and just delete everything or only one or two, or just the comments (via a drop down). Also you should be able to sort or view by who deleted it, or maybe by role.