Experimental modeling of the process of burning coal heaps and determination of the volatility of potentially harmful elements (PHEs) and organic pyrolysates – determination of the bonds of PHEs and organic pyrolysates on inorganic and organic phases of burned heaps – the comparison of geochemistry and petrology of unburned and burned coal heaps – the impact of weathering processes and rainwater on washout of PHEs from burned coal heaps – assessment of the effect of spontaneous revegetation and humus or topsoil to stabilize the PHEs – evaluation of the contamination of surface waters and stream sediments in the vicinity of coal heaps – geochemical modeling of the dispersion and attenuation of PHEs in river water – the sorption of PHEs on stream sediments – drawing up a conceptual model of migration of PHEs and organic pollutants in burned coal heaps – assessment of the impact of PHEs and products of pyrolysis of organic matter on the environment in the long term.