He said individuals and groups found places they liked and decided to come and camp there regularly. Then, when their situation changed, they often walked away from their gear rather than going back to take it out.
"Something happens. They get a girlfriend, or find they can't get there, or find a different place. They just leave their stuff there."
Especially in the 1980s and 90s, when helicopters were cheaper, people would make large sites and leave big tents. They would clear areas and leave beds, dishes and billy stoves there.
If some members of the group lost interest, the rest couldn't afford to fly the gear out.
Making such permanent camps, and clearing forest, is illegal. Sometimes DOC staff ignore them. Other times they have to remove them, at some cost.
"We usually pull it down, and burn what we can because it's bloody expensive to fly rubbish out of the bush," Mr Campbell said.
Staff will let people from "various circles" know if valuable items are found. The items are usually not claimed, because the owners don't want to pay the costs of the clean-up.
"Someone might have left their best axe and spade in there. But they don't want to pay for the cost of flying it out."
