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Purpose is to mitigate the adverse environmental impact in the context of both territory and water resources while closing down of mining enterprises.Methods. Experiments and laboratory studies were carried out to determine a relationship between salt content and amount of common reed biomass buildup. Twelve reed tillers from a 50 m 3 pond in Donetsk Region were selected for the research; water is habitat for eight of the tillers, and remaining four tillers grow at the distance of up to a meter from the water level. Water and air temperature, length of the reed stems as well as their diameters were recorded during thirty-eight weeks (i.e. March -November). The amount of suspended matters was determined when filtration residues of 50 ml sample were dried out by means of a drier with their following weighing; total salt content within the water under study was identified using a weight method while evaporating 50 ml of the filtered water sample volume and its residue drying out. Findings.A relationship between salt content and common reed biomass buildup was confirmed; moreover, temperature range was determined in the context of which the greatest biomass buildup was observed basing upon the analysis of higher water plants use to purify high-mineralized turbid water. A scheme of air-lift drainage has been improved as for the drainage water disposal in the context of mines closed down by means of a wet method; the scheme makes it possible to control temperature of water being pumped out while varying a depth of water withdrawal from a mine shaft and helping provide practically year-round bioplateau action. Originality.For the first time, optimum thermal water conditions (i.e. 12 -22ºС) within a biopurification plant at the territory of a closed-down mine have been determined theoretically and confirmed experimentally; the conditions provide year-round 32% decrease in total salt content of water as well as 35% decrease in the amount of suspended matters. Practical implications.The obtained results are applicable to rehabilitate fertile soil layer within the disturbed territories of facilities of the closed down mining enterprises with simultaneous waste purification from salts and suspended matters.

Purpose is the prediction of coal self-heating and determination of the factors effecting the dynamics of emission of tracer gases (TG) used for routine control of coal self-heating within the production unit involving European approach. Methods. To determine the composition of mine ventilation flows, mine air was sampled into a rubber chambers with the volume of 1 liter; after that, gas content (%) was determined in State Militarized Mine-Rescue Service (SMMRS) gas analytical laboratory with the help of "SIGMA-SO-V" and "Kristall" gas analyzers. Arrangement of sampling points is specified according to the normative document. Sampling periodicity while identifying a threat of coal self-heating within the worked-out area was three hours; in terms of standard conditions, the periodicity was not less than once a day. Period of monitoring within the mine working areas is not less than 9 -10 days. Experimental observations were performed in terms of the production unit of "Pioner" mine and "Pokrovske" mine office.Findings. Innovative approach to routine control of coal self-heating taking into consideration TG dynamics has been tested in terms of the pillar system with return-flow ventilation of a mine section. It has been defined that within the area of expected place of coal self-heating, carbon oxide (CO) consumption within the mine workings was up to 20.59 l/min, and the worked-out area was the source of TG emission; if there were no signs of self-heating, selfheating was not more than 4 -6 l/min. It has been determined that the TG emission nature is effected by geological (coal grade, seam occurrence, and seam disturbance) and technological (development system, ventilation scheme, rate of stoping advance, downtime periods etc.) factors.Originality. It is for the first time when, in terms of mining-geological and mining-technical conditions of Donbas, the factors, determining dynamics of tracer gases within the production unit in terms of pillar system of seam development, have been defined.Practical implications. Possibility to use European methodology of routine control of coal self-heating in Ukrainian mines has been substantiated and validated.

Substantiation of the possibility for expanding the modern Aerogas Control (AGC) systems functions when using them to identify the processes of spontaneous heating, spontaneous ignition of coal and gas contamination at the mining site of the coal mine. Methods. This paper presents the dynamics study of selecting 15 air distribution gas samples from the specified places, using the MATLAB system and Simulink extension packages. Gas samples have been selected in the 14th southern longwall face of block No.10 at Mining Administration "Pokrovske" during March 23-27, 2019, where an emergency situation related to gas contamination occurred on March 15, 2019. Findings. The experimental data has been processed on the carbon monoxide emission in mine workings of the extraction area, longwall face, technological pipelines, and on air distribution. A carbon monoxide increase in mine workings has been determined from 0.0000-0.0002% in the air jet, incoming the site, to 0.0001-0.0003% in the jet, outcoming from the site. Moreover, maximal invasion of carbon monoxide to the stope mine working occurred during operations of breaking and transporting coal within the extraction area, and when these activities were stopped and there was no fresh beaten material, the invasion of carbon monoxide was reduced to the background content level. It has been proved that improvement of the existing AGC systems by adding the sensors for measuring tracer gases and airflow rate, as well as the "artificial intelligence" to information processing units, will make possible to determine absolute and relative readings for sources identification of spontaneous coal heating at early stages. Originality. For the seam d4 conditions, the nature and peculiarities have been revealed of the carbon monoxide emission and the effects of ventilation during extraction operations at the mining site, while previous known studies were devoted to the carbon monoxide emission from the seams k5, l1, m4 2 with a change in the granulometric composition. Practical implications. Constant monitoring of aerological threats will make it possible to take appropriate measures for limiting the ventilation and gas hazards effects, the danger of endogenous fires.

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