“…For example, in the tailings dams the content of some metals such as Cr ranges from 170 to 310 mg L −1 , Co = 10-240 mg L −1 , Cu = 15-254 mg L −1 and lead 6-34 mg L −1 . High uranium rich mine water with acidic pH decants continuously from abandoned mines into streams (Winde, 2006;Hobbs, 2011;Abiye, 2014;Abiye, et al, 2018). The high concentration of polymetallic contaminants in the groundwater was regulated by oxidation, leaching and precipitation processes besides water-rock interaction.…”