An Environmental Impact of Pyritic Bauxite from the Dajti Mine, Albania

The accelerated chemical weathering of bauxite due to acid atmospheric deposition and breakdown of pyrite was simulated using short-termed laboratory acid leaching at 20 o C. Pyrite-bearing gibbsite-boehmitic bauxite giving rise to a number of questions concerning ecology was tested along with oxic boehmitic bauxite from the Dajti mine and that from Mali Korites (Mali Thate Mts., SE Albania). The leachte of pyrite-bearing and sulphate-producing bauxite is enriched in the following risk elements: Cd, Be, Zn, Ni, Co, and much less Cr, Cu, As, and Pb. Toxic soluble hydroxy-alumina ions may be also released into the aquatic environment, because of high concentration in output leachate (563 mg/l). In contrast, the leachates of oxic boehmitic bauxites commonly contain much lower concentrations of toxic elements with exception of Cu (Dajti mine) and Be (new occurence of Mali Korites)