I suddenly twigged why you're itching to get at it - you're a landscaper aren't you? What a project!
It's true isn't it, if a group of us spent a couple of days on it it would leap out of the view, plain for all to see.
But I can imagine that the permissions and the legalities would be a major problem, and it wouldn't be wise to do anything without them.

Two things seem very urgent though - shifting the fly tipping and putting up a fence against the road to prevent a repitition. Not sure whether either or both of those costs would fall on the council or the landowner, and if we're going to talk to anyone I'd suggest it was the landowner first, as we don't want to be in the position of having shopped hin and caused him expense. It's urgent though, as if the fly tipping grasses over then a false profile has been established, and in this case profile is all.