That's a very funny image!!! someone perched precariously atop a compost bin!
But it wouldn't look quite like that. There would of course be a small wooden building to house the loos, sited on a slope so that the entrance to the toilet would be a few steps up on the higher side, and, the access for the waste would be dug out a bit on the lower side to facilitate access. Complete with ventilation and solar powered fan. At least that's the plan...