What is clean dirt?

Soil.

=]

My father always reminds me that it only becomes dirt if it gets on you and makes a mess. Otherwise, it’s soil.

uncontaminated? Kind of like antarctica has purest snow on earth

As in “Clean Fill Wanted”? It just means they need some earthish stuff to fill in
a hole, and they don’t want it to come from where there was an oil spill, or the Love
Canal where they used to store chemical wastes, or someplace where nuclear waste
leaked. Or have radon in it. Or dead people. Or…

This ad said “Clean Dirt,” not “Clean Fill.” But I suppose that it could be the same thing.

Dirt or soil that is clean like susanc just said
Now the expression “Dirt Clean” means something that is so clean is impeccable clean, right?