Tucano Gold Mine, page-3

… Agree with sircorp (and more)
The future environmental problems with contamination after mining in a tropical rainforest cannot be overestimated.

Q. What happens after the sulphide ore is milled, processed and sent to the tailings pile?
A1. Oxidation of the sulphide bearing mill product will continue for hundreds of years.
A2. Acid water will be produced and will toxify the surroundings
A3. The environmental authorities under public pressure will force (whatever mining company operates this at the time) remediation work.

Q. What if the solid product contaminates the local rivers a-la-Ok Tedi?
A1. Extremely expensive remediation work.

The reasonable hope of the current share-holders is that some pompous mug buys out BDR .