The article deals with the main problems, namely the emission of biogas into the atmospheric air, during operation and after the closure of MSW landfills. Biogas, which contains methane, is considered not only as a strong greenhouse gas, but also as a valuable fuel that can be used as an energy resource. To assess the biogas potential at the operating landfill, field studies were carried out, which made it possible to determine the intensity and composition of gas emissions. The main points of landfill gas sampling at the landfill have been selected. Methods have been worked out and the equipment necessary for environmental monitoring at a real operating landfill has been selected. Using gas-geochemical surveys, environmental monitoring of biogas emissions from the MSW landfill was carried out at 49 sampling points. Coordinates in the WGS84 coordinate system, maps of the concentration distribution of the main components of biogas (methane, hydrogen sulfide, carbon dioxide, oxygen) were obtained at a depth of 50 cm from the surface of the landfill body. A zone recommended for drilling biogas wells was selected and recommendations were developed for installing a degassing station and using biogas as a source of electricity

The substantiation of environmental and resource-saving technologies and technical means for the processing and disposal of man-made formations and waste from mining and metallurgical production into underground mined-out spaces (man-made voids) as components of hardening filling mixtures is given. This will ensure the safety of the day surface from destruction and the vital activity of the population living in the zone of influence of the mining region. It was found that for the mines of the State Enterprise "VostGOK" (Ukraine), the utilization rate of waste of own production for the hardening filling is from 0.45 to 0.68; hydraulic – from 0.56 to 0.75; free-flowing – 0.62, and the extraction of each ton of salable ore is accompanied by the output of 0.7–0.8 tons of waste. The research results can be used in underground mining of ore deposits of complex structure and mining and metallurgical production.

The possibilities of use of combined modifying additive in the production of polymeric materials from general-purpose rubber production wastes are considered. Such additives facilitate reduce of the exhaust of pollutants into the environment at the stage of waste processing. Inorganic salts, including sodium phosphate and ammonium sulfate in a certain ratio can be used as a combined modifying additive the results of the study confirm the advantages of using of this complex modifier in polymeric materials from rubber production waste to increase their resistance to thermal decomposition, fire and aggressive media in comparison with an unmodified product. It was demonstrated that the complex modifying additive is more compatible with ISK rubbers and less washed out from it than with SKS rubbers.

The results of assessing the possibilities of using of biomass of fallen leaves as a filler of composite polymer materials with a polyvinyl chloride polymer matrix are presented. Samples of composites with biomass of fallen leaves we obtained by extrusion and hot pressing method. The dependences of their physical and mechanical properties on the content of the filler were determined. These de-pendencies are given in the form of polynomial of the second degree. In terms of most physical and mechanical properties (with the exception of impact strength) composites with biomass of fallen leaves are superior to samples of wood-polymer composites with wood flour with a similar degree of filling. Made of a comparison of the effectiveness of three different plasticizers: dimethyl phthalate, dibutyl phthalate and dioctyl therephthalate. The most promising is the use of dibutyl phthalate as a plasticizer. It has been shown that the biomass of fallen leaves is an effective replacement for wood flour in the production of wood-polymer composite materials with a s fr.

The process of dissolution of copper crumbs with nitric acid without superposition and with superposition of alternating current of industrial frequency is investigated. The main parameters of the process of copper dissolution by nitric acid in the absence of nitrogen dioxide formation are determined. The technology of electrolytic dissolution of copper with nitric acid is proposed.

In the studies, the extrusion method of synthesis of foam-glass ceramic was used, which contributed to the intensification of the silicate formation process and a decrease in the consumption of the alkaline component by 1.8 times. It was found that samples of granulated foam-glass ceramic with a fraction of 5–20 mm have the required compressive strength and effective thermal conductivity, which allow their use in the construction of transport infrastructure in permafrost conditions. Considering the colossal length of the Arctic zone of Russia, the perspective of the proposed approach is the possibility of creating mobile complexes for the production of heat-insulating material near the construction of highways.

The assessment of the possibility of creating a plant-soil cover on an artificially created seal-gravel drainage layer with a rocky bed (h=110¸150 cm), on the disturbed areas of the adjacent areas of tailings storage facilities. Research for 2017–2019 shows that when sowing recult-vants with sowing standards of 150–200 kg/ha and doses of fertilizer N₆₀P₆₀K₆₀ and N₁₂₀P₆₀K₆₀ on an artificial substrate it is possible to form meadow formations with a density of grass 10–12000 pc/m2 and average productivity of 21–24 c/ha. A plant-soil-blooded blood with a turf layer of 8–10 cm is created with the simultaneous overlap of heavy metals of man-made substrates and elimination of pulp sands dusting, which contributes to the improvement of the microclimate of the environment.

An assessment of the efficiency and safety of the formaldehyde decontamination process containing solid waste of wood-chip boards by method of medium-temperature dry pyrolysis at the installation developed by the authors was evaluated. Sawdust of chip boards and coke ash residue after their pyrolysis were subjected to biological examination. The test objects were Daphnia magna Straus, algae Scenedesmus quadricauda and luminescent bacteria. It was revealed that pyrolysis of these wastes at the proposed plant will reduce the load on the hydrosphere and reduce the ratio of dilution of water extracts by more than half. Analysis of the composition of pyrolysis gases showed that the mass concentration of nitrogen oxides and carbon in the air of the working zone does not exceed the MPC of the working zone and MPC of settlements. The conclusion on environmental safety of the process of pyrolysis of formaldehyde-containing solid wastes at the proposed installation is made.

The methods of biotesting of the aquatic environment based on the representative of the duckweed family (lat. Lemnaceae) greater duckweed (Spirodela polyrhiza (L.) Schleid) were considered. A review is presented on the use of greater duckweed as a model object in biological testing, in partic-ular, when exposed to heavy metals salts. When cultivated Spirodela polyrhiza with the addition of heavy metals salts, a change in the growth and development of plants in the experienced line of plants was revealed, as well as a decrease in the content of chlorophyll a and b.

Regression and neural network model for predicting the required dose of coagulant, depending on the quality of river water supplied for water treatment, are considered, their comparative analysis is carried out. For modelling and forecasting, statistical data collected for the period from 2005 to nowadays. Regression models were built on the true values of the factors (water quality indicators) and on their first differences to eliminate the trend in the series. For the models built on the true values, the statistical significance, was confirmed, high values of the coefficient of the determination were obtained, the values of the approximation errors were 22–25 %. In neural network modelling, networks of the multilayer perception were used. Generalization error on the test set when using other type of networks (RBF-networks, Elman networks), was significant above. Computational experiments have shown that, in general, the accuracy of neural network models is higher than regression ones. The average learning error was 7–9 %, the error on the test set increases to 12–16 %. The reliability of the forecast is increased by training the network on more recent data and using a larger set of facts. An increase in the influence of indicators of permanganate oxidability and colour of the initial river water on the dose of reagents with a simultaneous decrease in the degree of influence of alkalinity over the last five-year period was revealed. This confirms the need to periodically update data for building models. Selected models recommended for implementation in industrial monitoring of water treatment technology at the enterprise.

The review and analysis of the long-term variability of the average annual and average air temperature for winter and summer, as well as the values of the amounts of atmospheric precipitation in St. Petersburg were carried out. The correlation between the dynamics of the values of these indicators and the intensity of atmospheric circulation over the North Atlantic in the form of the NAO1 index (North Atlantic Oscillation) was estimated. The possible environmental consequences of climate change in the region of St. Petersburg are justified.