Effluent water quality and the ochre deposit characteristics of the abandoned Smolník mine, East Slovakia

Abstract

This paper presents the results of a 20-year survey of selected physical and chemical parameters of mine drainage and associatedstream sediments at the abandoned Smolník deposit (East Slovakia). The Smolník mine was in operation intermittently fromthe 14th century for Au, Ag, Cu, Fe and pyrite (FeS2). In 1990 - 1994 the mine was finally closed and flooded. In 1997 a remediationeffort was initiated in an attempt to improve the quality of acid mine drainage (AMD) from the mine site. Monitoring of the AMD waterparameters has continued since 2000 in quarterly intervals. Considering the concentration of dissolved constituents and the flow rateof the AMD, the abandoned Smolník deposit brings about continuous loading of more than 500 kg of dissolved metals per dayto the adjacent Smolník stream.The ochreous precipitates formed from AMD stream were characterized by elemental analysis, X-ray diffraction and scanningelectron microscopy. Schwertmannite was the dominant solid phase in the precipitates. The chemical analysis of AMD and the elementalcomposition of related sediments indicated selective scavenging potential of the precipitates for arsenic and other metal species.

Keywords

• Acid mine drainage
• water quality
• monitoring
• sediments
• schwertmannite
• iron
• sulfate precipitation