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.

The stored waste from mining, mainly represented by tailings dumps and landfills, needs constant monitoring. On the one hand, they often pose a danger to the environment and people, on the other, with the development of new technologies, they are considered as a source of recycling and extraction of valuable components. In cold climatic zones, waste storage, stable storage facilities, and the organization of a monitoring system have a number of special features. Negative temperatures, freezing and thawing cycles lead both to increased release of potentially toxic substances outside landfills and tailings dumps, and to a violation of the integrity of enclosing structures. The problem is compounded by global warming, which leads to greater mobility of the upper layers due to thawing of frozen ground. The problems of monitoring in cold zones are caused by the high cost of its implementation due to the remoteness of the territories and the difficulties of working during the winter period. In such conditions, geophysical observation methods become promising, since they do not violate the integrity of the studied objects and provide an autonomous energy-saving mode for a long time. The article discusses the possibilities and features of using geophysical technologies for monitoring stored mining waste in cold climatic zones. Examples of study in Russia, Canada, the Nordic countries of Europe and other countries with similar climatic conditions are used.

Barite is one of the critically important minerals in several industries, including the fuel and energy, nuclear, and medical sectors. For decades, its extraction did not require any complex techniques; however, with the depletion of rich barite-bearing veins around the world, the circumstances have changed. While the demand for barite is growing widely, it is necessary to optimize and improve the existing methods for benefication of barite and barite-containing ores, and create new approaches to extracting this mineral, as well as develop technogenic barite deposits accumulated in large quantities during the previous ore production. Dumps and tailings often demonstrate high barite content, while new mining technologies make its extraction cost-efficient. Russian and foreign papers of the last 14 years provide data on the current state of primary and technogenic deposits, areas of barite use and the approaches employed for its benefication. Considering the expansion of the range of barite applications, the growing need for the mineral in the oil and gas industry and the difficulties in developing new barite deposits in Russia, the importance of new approaches to the enrichment of ore tailings in polymetallic deposits is revealed.