I think this is a real future niche for biohydromet – these can be the win-win situations we look for.
In many ways, this is what really inspired me with the Kasese operation in Uganda. While cobalt recovery was the primary driver in that case, the result is less reactive residues. BacTech are ostensibly putting the remediation first, but (I presume) will not go ahead if the value of the metal recovered does not cover the OPEX and CAPEX.
We have looked into the use of accelerated leaching of heap material to reduce the time scale of AMD production while I was at UCT and I do think there is scope for biohydromet as part of a larger remediation strategy. Even if the value of the metals produced don’t cover the full cost of the leaching operation, so long as the overall position is remediated (i.e. less active) mine waste the recovered value can be seen to offset the cost of remediation (which is necessary in any case).