A toilet seat replaces the lid when in use. At the end of the trip, the box is emptied at an RV dump station or city sewage treatment plant. To use the poop tube, scoop waste from the ground into a paper lunch bag, roll up the bag, and slide it into the tube. Screw down the lid, and the poop tube can be strapped to the outside of your pack or lashed with other gear to canoe stalwarts or bike racks. Ask at the district office or ranger station for the best place to dispose of collected waste once you are out of the backcountry.
Most national parks have a sewage treatment plant.
On national forests and BLM lands, drive to the nearest town with a sewage treatment plant. Please do not put waste into outhouses unless instructed to do so. There's too big a risk of spillage, and most outhouses are drained on a regular schedule, with little room for excess waste. Finally, never put human waste into trash cans or dumpsters. The Cat Hole Contrary to popular wisdom, burying feces in a cat hole does not necessarily hasten decomposition.