The article presents the results of a comprehensive survey of the trench at the Tuvakobalt plant, which contains waste from the hydrometallurgical processing of Cu-Co-Ni arsenide ores from the Khovu-Aksy deposit. Using electrical resistivity tomography, geoelectric maps and cross-sections were obtained, and a 3D model of the storage was constructed. A highly conductive (low-resistance) zone has been delineated in the central part of the trench – a substance with relatively higher moisture content than the surrounding side parts. The groundwater uncovered in the pit faces consists of mineralized solutions with a high arsenic content (up to 15 mg/l), which indicates active processes of interaction between seasonal waters and the trench material, as well as the accumulation of dissolved forms of metals and metalloids in the liquid phase of the highly conductive zone. This zone, which is narrow at the surface, widens towards the bottom of the trench and extends deeper than 40 m, which indicates the possibility of high-mineralized solutions entering the underground aquifers. Another pathway for the migration of pollutants is through emanations from the surface of the storage. A high concentration of chemical elements, including potentially toxic ones, enters the surface layer of the atmosphere with vapor-gas flows, as established by collecting and analyzing condensates. The forms of element migration in these flows were determined through laboratory experiments involving the capture and deposition of substances carried by the flows. The composition of the flows is primarily made up of amorphous organic compounds, with a small proportion of chlorides and sulfates; metals and arsenic are transported in the true gas flows in combination with organic ligands. The results of field and laboratory studies of the storage state indicate the presence of channels for water migration into underlying horizons, and under favorable conditions, a vapor-gas mixture rises from the surface, carrying metals and arsenic in a volatile, bioavailable form.

The article presents the results of a comprehensive study of the stored waste from the Berikul gold mining plant (Kemerovo Region), using geochemical, geophysical, and econometric methods. Using electrical tomography method, geoelectric sections (transverse and along the dam’s contour) and a 3D model of the storage facility were constructed; they describe the location of zones with a specific electrical resistance varying within the range of 3-800 Ohm·m, which makes it possible to determine the configuration of conductive zones in the internal structure. From the stored waste, which has a thickness of 5-7 m, mineralized water filters into the underground horizons, resulting in the formation of a depression characterized by an electrical resistivity (ER) of ~200 Ohm·m, which is significantly lower than the ER of the surrounding rocks. The zone of reduced resistance extends deeper than 40 m, which clearly indicates the vertical spread of the drainage system, possibly along a weakened zone in the granodiorite massif. Additionally, the formation of highly conductive areas is clearly visible on resistance maps up to 20-40 m. Samples of solid matter and water were taken from the resulting small bodies of water to determine their chemical composition. The stored waste is characterized by a contrasting composition in different parts of the storage facility; accordingly, both the physicochemical parameters and the ability of elements to transfer into solutions vary over a wide range. The majority of the waste material produces an acidic reaction in the pore waters and has a high mineralization. Water extracts from the samples cakes indicate a significant proportion of easily soluble compounds in the waste material. The content of metals and metalloids in water from surface ponds (maximum Fe 7800, Al 590, Zn 160, As 1600, Be 0.022 mg/l) indicates a high environmental hazard posed by these waste materials, while also suggesting the potential attractiveness of the site for the further recovery of useful components. An assessment has been carried out of the damage caused by the storage facility to water bodies within its influence zone – 470 million rubles.