Copper Speciation Assessment in Aquatic Ecosystem Affected by Historical Mining Activities

Abrud river is an aquatic ecosystem exposed to anthropogenic influences exerted by long-term mining. This study examines the level of copper concentrations by assessing both total copper content and ionic forms in surface waters and sediments. These components were studied in 10 control sites located in a section of river that has been exposed to acidic mine water spills and leaks. The partition coefficient (kd) of copper between the liquid and solid phase suspension was calculated, and filtered and unfiltered liquid samples were subjected to analytical laboratory determinations required to create a complete image of the chemical composition of the matrix. The results were integrated into the mathematical model PHREEQC to determine the weight of chemical species of copper. Speciation of copper in sediment was performed using sequential extraction procedure. We conclude that the sites most affected by pollution are those with the highest levels of the bioavailable mobile fraction.