OCHRE PRECIPITATES AND ACID MINE DRAINAGE IN A MINE ENVIRONMENT

This paper is focused to characterize the ochre precipitates and the mine water effluents of some old mine adits and settling pits after mining of polymetallic ores in Slovakia. It was shown that the mine water effluents from two different types of deposits (adits; settling pits) have similar composition and represent slightly acidic sulphate water (pH in range 5.60-6.05, sulphate concentration from 1160 to 1905 g.dm-3). The ochreous precipitates were characterized by methods of X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and B.E.T. method for measuring the specific surface area and porosity. The dominant phases were ferrihydrite with goethite or goethite with lepidocrocide.