The Use of Hydrochemical Zoning to Predict Water Hazards: The Example of the Olkusz-Pomorzany Zn-Pb Mine

Abstract

A water hazard is one of the greatest dangers in mining and tunneling operations and the issue of predicting water hazard zones has been extensively discussed in the literature. However, the currently used methods require a highly detailed understanding of hydrogeological conditions or have major limitations and often produce unreliable results. This paper describes the use of hydrogeochemical anomalies as an indicator of impending mine water hazard zones. The proposed method uses the concentration of Cl ions in water extracts from Permian rock samples collected from the face of the mine workings. The concentration of Cl ions in the water extracts strongly correlated with the concentration of this ion in the pore solutions extracted from the same rock samples. Additionally, the concentration of Cl ions in the pore solutions exhibited a very strong correlation with the concentration from the Permian leaks. Thus, the decreasing concentration of Cl ions in the water extracts was deemed a reliable signal of an approaching water hazard zone. In the hydrogeological conditions present in the Olkusz-Pomorzany mine, this method enabled the detection of the moment when a water hazard zone was ≈ 200–250 m away.