Master recession curves of 117 karstic springs from Middle and Upper Triassic carbonate aquifers in the Slovakian territory of the mountainous Western Carpathians were assembled from gauged discharge data. Identified slow-flow and fast-flow components were very diversely represented. Fast-flow components were missing in 47% of springs. In another 20% of springs, only fast-flow components were recognized, while slow-flow components were absent. Simultaneous discharge of both slow-flow and fast-flow components was found at 39 springs (33%). Known geology of recharge areas enabled examination of the impact that outcropping dolomites and/or limestones may pose to the discharge recession. It was found that dolomites in springsheds significantly affect slow-flow components, but do not influence the occurrence of the fast-flow ones. The purely fast-flow-driven recession was present both in limestone and dolomitic springsheds, but merely one fast-flow component was typical for the dolomitic ones. Two or three fast-flow components may appear in "purely limestone" springsheds. Recession coefficients of slow-flow components were within the interval of 0.0004-0.18 days −1 and those of fast-flow within 0.0017-0.31 days −1 . The duration of the fast-flow components is mostly several days or several tens of days, while the theoretical duration of slow-flow may last for decades. Storage in matrix, fractures or conduits of the saturated zone cannot be separately estimated because, in discharged volumes, water from unsaturated and epikarst zones is included. Variable shapes of assembled master recession curves point to the important influence of unsaturated and epikarst zones on the discharge recessional patterns of karst springs.

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Seasonal hydrochemical regime of water flowing out of the Rochus Fe-Cu mine in the Spiš-Gemer Ore Mts. was monitored by discharge measurements and laboratory analyses of mine water chemical composition. Regression analysis of these data showed a statistically significant dependence of concentration of many important chemical elements on mine water discharge. The obtained data made it possible to better understand the processes of mine water chemical composition genesis, as well as to determine in more detail the degree of its environmental impact. Geochemical calculations and forward geochemical modelling suggest that chemical composition of mine water is formed in three stages. First phase takes place in the aeration zone of the mine, where ankerite dissolution, intensified by pyrite oxidation, dominates. In saturated zone of the mine, ankerite dissolution is probably controlled by CO2 input in open carbonate system. These two main geochemical processes take place permanently and at the time of low flow conditions they lead to relatively stable composition of water outflowing from mine. In time of higher flow conditions, concentration of SO4, Mg, Ca, Na and As significantly increases, probably as a consequence of mixing with stagnant water from deeper or hydraulically more isolated parts of the flooded mine. Water flowing out from mine enters the Rudniansky potok creek and contaminates it mainly by manganese. The limit for Mn content in surface water is exceeded here at the time of low flow conditions – usually for 180 days a year. Anomalous concentrations of SO4, Mg, As and Sb in mine water are sufficiently diluted in stream water were they do not exceed environmental limits.