muddy waters in a decantation pond. toxic residuals from a copper mine decating in a settling basin

settling basin decantation lake mining separation opencast residuals chemical toxic waste water mud copper gold geamana rosia montana romania poieni extraction pond muddy structure industry industrial pollution turbidity suspended acidity heavy metals wastewater discharge environmental barrier flooded baffle village barrage submerged sedimentation toxicity exploitation contamination poison leak mineral taint geology waters decating geological landscape decantating decanting pond basin landscape