[en] In the present work leaching of ash from coal-fired power plants is described and the elemental analysis of coal, ash and leachates has been performed by neutron activation analysis, atomic absorption spectrometry and ion chromatography. The research concerns precipitator ash from powder-coal fired utilities, desulfurization ash from a dry-scrubbing process and fabric filter ash from a fluidized-bed boiler. Reproducibility of shake tests and column leaching has been studied. In the shake tests a wide range of solid to liquid ratios is applied, which allows extrapolation to column conditions. Column experiments carried out in upflow at a fixed flow-rate of approximately 1 cm per day showed good column performance and proved that equilibrium is reached fairly rapidly. A classification of precipitator ashes with respect to leaching behaviour is given, which allows an estimate of leaching characteristics beforehand. In relation to this variability in coal and ash compositions has been studied. (Auth.)