Treliver was a new one on me. An interesting example of the power of the internet, in some ways.
http://www.cornishmineimages.co.uk/treliver-farm-project/ https://www.bbc.co.uk/news/uk-england-cornwall-22357712 (£64m surfing industry in Cornwall? Really?)
... and a listing on LinkedIn, which (and I hadn’t realised that this happened) has collated details from entries by those involved and created a listing out of those (to be fair, it does say that no one is updating or operating that listing, but it’s an interesting concept. A sort of modern version of “enter Rumour, painted full of tongues”)
I wouldn’t have thought that re-processing old dumps, was a particularly radical concept. Whear Tin (?) used to do that, down in the Brea Valley, in my student days. I seem to remember that their main profit centres were selling the resulting washed crushed granite to the Camborne bypass construction site, and letting student accommodation.
There was also a short-lived operation dredging sands from, I think, Roscroggan and the-streaming the arisings.
Come to that, there are plenty of abandoned small-scale speculative sites around the old mining areas. I’m only surprised that anyone could care less about them, in the present time.