In situ leaching is another possibility. This article looks at...

In situ leaching is another possibility.
This article looks at using an electrode to attract ionic forms of gold in solid rock!
https://www.sciencedirect.com/science/article/pii/S0304386X1830029X

EK -ISL, if it were to work would have low capex, be environmentally friendly and Very Very profitable.
Given the extraordinary nature of the BBX ore, it may be the ideal testing ground for this new technology

It may also be possible to use existing drill holes.Infact, as start to prove up the ore,make another collector point
There is a lot of research going on in this space:

https://www.sciencedirect.com/science/article/pii/S0304386X17306321

This may line up BBX to have
-the richest and largest orebody in the world
-the lowest ASIC globally
-the least polluting methodology
-the wealthiest shareholders in the world