I guess this is what they mean by "dump camp."
All one needs is a piece of PVC pipe with a sealed bottom and screw top, some kitty litter and brown paper bags. You go in the bag, put in some litter, roll it up and place it in the pipe which is carried outside the pack.
I believe this is what the big wall climbers use on El Cap. In fact, I thought I read Yosemite NP requires this outfit.