Responsible behaviour by the public
The Access Code says:
If you need to urinate, do so at least 30 metres from open water or rivers and streams. If you need to defecate, do so as far away as possible from buildings, from open water or rivers and streams, and from any farm animals. Bury faeces in a shallow hole and replace the turf.
Responsible behaviour by land managers
There is no specific guidance in the Access Code for Land Managers on human waste.