I pan a lot and we have a mapping app with our states Dept. of Natural Resources. Basically it's a layered map of mineral and water rights. Where I live a lot of stakes have been claimed but the state also has places where they won't let people have mineral rights and anyone can pan for gold, and use a high banker, but they don't allow sluice boxes or anything like that in the streams.
Just googleing and knowing what it takes in my state I would start here.
https://www.dmme.virginia.gov/webmaps/DGMR/Also your layered map is as difficult as ours to figure out so my link might be wrong as I didn't really look into it to much.
And in our state you have to renew your "claim" every year so if you snooze, you lose. A coworker took over a claim.
>my minimalist panning stuff in pic 