That particular mine pit will probably be fine (for reasons of geology and tailings treatment, etc . . . " However "
The Berkeley Pit in Butte, Montana, is the cautionary tale everyone wants to avoid.
The 1.6km-by-800m copper mine closed in 1982 and gradually filled with water irreversibly contaminated with sulphuric acid, copper, arsenic, cadmium and zinc from the surrounding rock.
In 2016, some 3000 migrating snow geese were killed when they landed on the toxic brew. The US Environmental Protection Agency (EPA) must pump out and treat the water – forever.
and worth noting that articles such as the one linked above are part of a swelling campaign by land holders and others with leverage to bake clean up costs into resource licencing.
After the geese died, researchers found a microorganism living (and thriving) in the extremely toxic lake. This microorganism was filtering out the toxins 900 times more effectively than any other known organism[1]. The origin of the microbe was the gut of the geese. Radiolab included this story in one episode[2].
That particular mine pit will probably be fine (for reasons of geology and tailings treatment, etc . . . " However "
[source] https://cosmosmagazine.com/earth/sustainability/australias-p...It's certainly worth highlighting that past Western Australian mines have not ben rehabbed to any notable standard:
Mine rehab in WA is the pits: Inquiry finds few success stories (2017)
https://www.watoday.com.au/national/western-australia/mine-r...
and worth noting that articles such as the one linked above are part of a swelling campaign by land holders and others with leverage to bake clean up costs into resource licencing.