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Development of alternative energy sources are increasing now, but the use of minerals still plays an important role in the industrial sector, and Ukraine is no exception. DTEK Energo is a key player in Ukraine's coal industry. 13 mines and 4 coal concentrators represent production capacities of this segment. Dumps and sludge storages contain about 1.3 billion tons of rocks with an annual replenishment of about 60 million tons. These areas occupy large areas and require reclamation in the future. This paper presents the results of physico-chemical analysis of DTEK SU "Heroiv Kosmosu" coal mining dump, namely such indicators as: pH and electrical conductivity of the substrate (EC), nutrient content, concentration of rare earth elements. The results of the obtained data in the future allow to choose the best method of reclamation, involving plants, with subsequent bioleaching of rare earth metals.

Biochar, obtained by pyrolysis of coniferous wood, as an adsorbent for removing chromium ions from aqueous solutions was used. Biochar samples were examined using X-ray, X-ray fluorescence analysis, DTA, TG, FT-IR, SEM microscopy. The ash composition was not significantly dependent on temperature and included Mg, Ca, Ti, P, C, O. X-ray phase analysis showed the presence of silicates, calcium and magnesium carbonates. IR spectroscopy confirmed the presence of organic groups. The adsorption experiments were carried out by varying the dosage of the adsorbent, the initial concentrations of chromium ions, and the contact time. The structure used biochar has no distinct pores apparently due to filling by nanoparticles chromium compound. To clarify the kinetic parameters and the mechanism of the adsorption process, kinetic models of first, second order and intra-particle diffusion were used. The kinetic model of the first order describes the kinetic curves in the best way.

The results of the experiment with biochar as a soil amendment are presented. Two energy crops (Miscanthus × giganteus and Helianthus annuus) were grown in the vegetation containers with two types of marginal lands. Low humus black soil Low humus black was taken in flood plain of Kilchen river. Red-brown clay was taken from the quarry board 15 yeas ago to create reclaimed mine land in site near “Blagodatna” coal mining tailing. It was defined that the biochar addition intensifies growth processes from 7‒30% (Helianthus) to 20‒88 % (Miscanthus). For Miscanthus, the effect was more pronounced on black soil, and for Helianthus on red-brown clay. Due to the biochar application, the plant capacity to take up heavy metals by above-ground organs decreased. As a result, the heavy metal content in leaves and stems has reduced by an average of 10‒25%. However, because of the gain in biomass productivity, the uptake level of some heavy metals has increased. Especially, this was characteristic of the Miscanthus leaf biomass. So, the uptake of heavy metals by leaves increased from 28.1% (Pb) to 62.9% (Fe) on the black soil, and from 20.3% (Cu) to 46.6% (Zn) on the red-brown clay. The addition of biochar had a slight effect on thermolysis passing of Miscanthus and Helianthus biomass. So, in Miscanthus, duration of the process has grown shorter. The rate of thermal degradation in the leaf biomass was greater, which is especially noticeable in the region of hemicelluloses destruction. In the stem biomass a pronounced increase in the thermolysis rate was noted in the region of volatile components evaporation (on the black soil) and during the cellulose decomposition. Besides, under the impact of biochar, biomass combustion was more complete (by 5.1% on the red-brown clay and by 30% on the black soil). In leaf biomass of Helianthus, the onset of thermolysis has shifted toward higher temperatures. In addition, the magnitude of the thermal effect was greater at almost all stages of decomposition. In stem biomass, thermal effects also increased, but only slightly. Under the influence of biochar, the first stage of decomposition was faster. In biomass taken from red-brown clay, the rate of hemicellulose degradation also increased. In biomass taken from black soil, biochar application contributed to more intensive decomposition of lignin. After combustion, the share of residual mass in stem of plants grown on black soil with the biochar addition increased by 30%. The opposite effect was observed on red-brown clay: the share of residual mass decreased by 49%. Besides, the thermal stability of stem biomass grown on the substrates using biochar lessened by 8‒16%.

The neutralization of toxic mine rocks with additional of soil and loess like loam mass leads to a significant decreasing of salts migration at the contact zone. The mathematical model was working out follow general principle where mine rock is pollution source, but soil and loess like loam take place as volumetric filter for water-soluble salts. MathCAD file with commands for solving the problem forecasting the process of vertical salinization of reclaimed minelands was developed. The prospect for the numerical model using up to the most accepted range of values with experimental data shown. The irrigation of reclaimed minelands in the Western Donbass possible in the case of the dilution of the mine waters of aquifers with the Samara river water.

The ability of biochar as a soil additive to influence productivity, accumulation of heavy metals and thermal characteristics of energy crops was studied. Maize, Sudan grass and Sweet sorghum were grown in containers with low humus black soil and red-brown clay. It turned out that the addition of biochar improves seed germination from 1.5% to 15% and promotes an increase in the growth of aboveground biomass and roots. For Maize and Sweet sorghum plants, the most pronounced effect is revealed on red-brown clay, and for Sudan grass on black soil. Biochar indirectly affects the intensity of accumulation of heavy metals by reducing their mobility and availability to plants. In both variants of the experiment with Maize, the application of biochar had the greatest effect on the accumulation of zinc. In the experiment with Sudan grass on black soil, the greatest effect was observed for manganese, and on red-brown clay for zinc and lead. In the experiment with sugar sorghum, the most pronounced reaction took place for copper on both substrates, and for zinc only on red-brown clay. The biochar addition led to the more complete combustion of the Sweet sorghum biomass grown on black soil and, conversely, increasing the ash content of the biomass grown on red-brown clay. During the combustion of Sudan grass biomass in the trial with red-brown clay, the addition of biochar contributed to the significant reduction in thermolysis duration and shifting of the extremum point of cellulose decomposition to the area of lower temperatures. In the case of Maize biomass, a similar effect was observed, but only in the trial with black soil.

The object of research is the effectiveness of the use of vermicompost products of vermicultivation in the practice of phytoremediation of degraded and technogenic contaminated lands. One of the problematic aspects in solving the scientific problem of reclamation of lands degraded as a result of technogenic activity is the long-term stage of biological restoration of the disturbed landscape. For a more efficient and quick reclamation, it is advisable to create a phytocenosis from tree-shrub vegetation, resistant to negative environmental influences. Well-tested biotechnologies of vermicultivation create the prerequisites for the use of waste products of the colonies of the worms of the genus Eisenia in the form of composite vermicompost briquettes for the needs of land phytoremediation, and it is proved in the study. The analysis of literary sources using modern technologies of vermicultivation and the use of vermicompost products for the needs of agriculture and land phytoremediation is carried out. The growth process of the biomass of worms of the Eisenia fetida species and the accumulation of vermicompost over time depending on the temperature of the medium are studied. The results of laboratory bioindication experiments with composite briquettes, consisting of vermicompost, loam and seeds of wild cereals, are presented. It is determined that the ratio of vermicompost and loam in the composition of composite briquettes, which is the most optimal for plant growth indicators, is 60:40 and 40:60 by mass, which makes it possible to justify the phytomeliorant working mixtures for biological land reclamation technologies. Laboratory studies have shown the promise of using vermicompost as a product of vermicultivation in the form of composite briquettes in the practice of phytoremediation of disturbed lands.

This paper presents the result of studies of the geostatistical and geospatial assessment heavy metal pollution in soils caused by various technogenic sources to assess the environmental impact of industrial agglomeration activitiy in the Pavlograd city. The main sources of technogenic pollution in the Pavlograd city and suburban areas are industrial enterprises, coal-fired plants, mine dumps and other. The vast number of analyzed soil samples with weakly acidic pH values from 6.3 to 6.8 is characterized as loam (63 %), the rest are sand (33 %) and clay soils (4 %). The correlation matrix of metals data indicates positive correlation with correlation coefficient r 2 > 0.5 among texture – Ni (0.705) and Pb – Zn (0.695) within the Pavlograd city area. In the case of Cu (2.73) and Cd (4.27), the geoaccumulation index indicated “moderately to strongly” and “strongly to extremely” polluted soils accordingly. Means of pollution index (PI) for heavy metals were between uncontaminated ( PI ≤ 1) and of moderate contaminated soils ( PI ≥ 1).The results of this study show that industrial enterprises’ activities lead to heavy metal contamination in the topsoil of the studied sites and close to the background values. Similar properties were confirmed by principal component analysis (PCA) and cluster analysis. The PCA and cluster analysis results indicate that Cd, Ni, Pb, Cu, Zn and Mn in topsoil were affected by the technogenic activity. The spatial distribution characteristics of Cu, Pb, Cd and Zn in the geochemical maps are also similar. Highlighted are some of the halos in Pavlograd of high density of total soil contamination with heavy metals. The metals come from anthropogenic sources, mainly produced with four industrial enterprises in Pavlograd city. Mostly they are concentrated in the Southeast and West of the city and suburban areas of the Pavlograd district. Therefore, it is necessary arrangements to predict of the development of ecologically dangerous state of environmental pollution within the area of industrial enterprises of city.

Plasma method is used to synthesize manganese ferrite. The basic properties of ferrite are determined by IR spectroscopy, UV spectroscopy, X-ray phase analysis, vibration magnetometry. The paper shows that the use of magnetically controlled sorbent allows to purify waste waters from chromium (III). The process of adsorption of chromium cations (III) is investigated. The kinetics of the process is studied. To describe the equilibrium isotherms, the experimental data are analysed by the models of Langmuir, Freundlich isotherms. Pseudo-first order, pseudo-second-order, and Weber-Morris are used to elucidate the kinetic parameters and mechanism of the adsorption process. It has been established that the removal of Cr (III) cations is described by the pseudo-second order of the Langmuir reaction and mechanism.

Surface evaporation rates that are greater than precipitation rates lead to upward salinization processes and, consequently, man-made contamination of the covering surface layers on coal dumps in Western Donbass, Ukraine. The effectiveness of capping the mine dumps with different layers of black-soil mass, both with and without a shielding layer of loess-like loam, was studied in order to develop the optimal scheme for the reclamation of these dumps. Principal component analyses were carried out in order to reveal the regularities of the upward salt migration to the surfaces of reclaimed coal mine dumps. The parameters of the layer-by-layer variation of the physical and chemical data in soil water extracts (namely, pH, total salinity and concentrations of bicarbonates, chlorides, sulfates, calcium, magnesium, sodium and potassium) which were obtained in 1987, 2003 and 2016 along the reclaimed profiles of various models of technogenic edaphotop, gradually acquire a stable-equilibrium state of mineralization in space and time. The alkaline barrier is the main factor for pH-changes and profile salinization of reclaimed land.DOI: http://dx.doi.org/10.5755/j01.erem.74.2.19940

The accumulation in different environmental objects of many toxicants defines the real risks for biota and human health. An especially serious risk for all living organisms is presented by environmental mutagenes that can affect the hereditary apparatus of somatic and sex cells, resulting in cancer increases and other ecologically dependent pathologies. Therefore, an investigation of mutagenesis in cells at genetic level is very urgent and real. Biological monitoring, which includes genetic and cytogenetic monitoring, provides a useful tool for estimating the genetic risks deriving from integrated exposure to a complex mixture of chemical, physical and biological environmental agents. A positive association between occupational exposure to complex pesticide mixtures, and the presence of different cytogenetic pathologies including micronuclei (MN), has been detected in the majority of studies. The application of cytogenetic testing, using the micronucleus assay (MN-test) on exfoliated buccal cells of children, substantiates the estimation of total mutagenicity in the studied territory in which they live. A positive modifying cytogenetic influence of natural adaptogens was established.

Mechanisms of humic substances (HS) physiological activity in relation to different organisms at a molecular—cellular level were studied. Adaptation mechanisms of HS action under radiation and chemical injuries were examined. Antimutagenic and detoxifying properties of HS were revealed and a usage of physiologically active HS for remediation of both biotic and abiotic components of the environments and human's health recovery was proved. By the example of industrial area nearby the Dnepr River the HS applicability for remediation of disturbed soil was demonstrated. Experimental evidences of reduction of genetic damage caused by chemical and physical stress factors in the presence of HS were obtained using various bioassay techniques. A theoretical basis for HS application to retard uptake of contaminants by plants from soil and to improve biota resistance towards anthropogenic factors was developed. Recommendations on improving environmental conditions, recovering human health, and remediation of polluted areas were elaborated based on application of HS.