cause a problem with the mining practice?

$q,$

They oridize ferrous iron $($Fell$)$ back to ferric iron $($Felli$)$ thus helping to propagate the cycle in a positive feedback loop while contributing to the release of sulfuric acid

They produce organic acids $($e$.$g$.$ lactic acid$)$ during fermentations which lowers the pH of the environment

They consume a large amount of the pyrite, thus making mining operations less profitable

They excrete toxins that make the effluent uninhabitable for other species