Potash fertilizer production is one of the most important economic activities. Historically, potash mining has had a significant impact on the environment, often with catastrophic consequences. The purpose of this paper is to summarize the results of studies on the environmental impact of potash mining using the example of the Verkhnekamskoe potash deposit. The deposit is located in the central part of the Solikamsk depression in the Pre-Ural foredeep (Perm Krai, Russia). All the main features and problems of underground mining of water-soluble ores and potassium fertilizer production are considered using the example of one of the world’s largest potash deposits. This paper looks into the specifics of the material composition of waste, its disposal, underground mining issues associated with the solubility of salts, and the risks of groundwater inflow into the mine workings, which causes flooding of mines. The results of all surveys show that potash mining affects the atmosphere, surface water, groundwater, soil, and vegetation. The most effective measure to reduce the adverse environmental impact of potash mining at the Verkhnekamskoe Deposit is hydraulic backfilling of mine chambers, which protects the underground mines from flooding, minimizes ground subsidence, and reduces the area of potash waste.

Specific activity of natural radionuclides 226Ra, 232Th and 40K was measured by gamma spectrometry in samples of soil and bottom sediments of rivers on the territory of potassium salt deposit development in order to collect information on radionuclide distribution. According to the results of...

The development of coal deposits is accompanied by negative environmental changes. In the territory of the Kizel coal basin (Perm Region, Russia), the problem of contamination of water sources by acid mine waters and runoff from rock dumps is particularly acute. Mine waters are acidic (pH 2–3), with high mineralization (up to 25 g/L) and significant content of sulfate ions, iron, aluminum, manganese, toxic trace elements (As, Co, Ni, Pb and Zn). They are formed as a result of the interaction of underground waters from flooded mines of the Kizel basin with coal and rocks of dumps with high sulfur content (15%). Uncontrolled inflow of mine water into rivers (about 22 million m³ annually) leads to significant amounts of iron and aluminum hydroxide precipitation. These precipitations are in active interaction with river water, polluting the rivers tens of kilometers downstream and are entering the Kama reservoir. Studies of alluvial precipitation can be considered as a method of control and predictors of technogenic water pollution. The mineral composition of river sediments was studied with the application of different methods, including studies of sand-gravel and silty-clayey sediments. The sandy-gravel grains in the bottom load are mainly composed by natural minerals and are represented by a significant number of particles of coal dumps, slags and magnetic spherules. The silty-clayey material, mixed with natural minerals, contains a significant number of amorphous phases with a predominance of iron-rich substances, which may actively concentrate toxic elements. The presence of jarosite, goethite, basaluminite, lepidorocite and copiapite in silty-clayey sediments are indicators of the influence of mine waters.

The Kosva Bay is permanently affected by acid mine drainage (AMD) from Kizel Coal Basin in the Perm Krai of Russia. This discharge is released in the middle part of the Kosva River from the abandoned mines. This study investigates the current trace element (TE) concentrations for Zn, Cu, Pb, Ni, Cr, Cd, As, and Hg and the mineral composition, major oxides, grain size of sediments, and acute toxicity using two test organisms within the site of AMD downstream from the Kosva River and up to the Kosva Bay of Kama Reservoir. The objectives of this study were to analyze the quality of sediment and level pollution of Kosva Bay using pollution and ecotoxicological indices. The environmental indices, namely the contamination factor (CF), the geoaccumulation index (I_geo), and the potential ecological risk factor ($E_r^i),$ indicate contamination by Cr and Pb in sediments at the site of AMD, with the highest values for Cr, Cu, and As in the Kosva Bay sediments downstream of abandoned coal mines. The results of I_geo and CF average values in bay of sediments showed different degrees of contamination, from moderate contamination to considerable contamination, respectively. According to the potential ecological risk index (RI) values, the Kosva Bay sediments exhibited low to moderate risk, and As and Cd have the highest contribution rate. According to LAWA and the Polish geochemical classification of sediments, sediments of the bay correspond to the highest levels (IV–III classes) for Cr, Ni, and Hg. Based on the SQG_C, Hg, Cd, Cr, and Ni are the most probable for resulting in adverse effects on aquatic organisms in this study. The results of this study indicate that complex pollution and ecotoxicological indices must be supported by ecotoxicologal tests. High precipitation totals, low evaporation rates, and flow regulation stream by the Shirokovsky Reservoir located upstream from abandoned coal mines provide significant fluctuations in streamflow, which is probably the most important factor controlling the distribution and mobility of TE in the studied sediments.

In terms of anthropogenic impact of mining and processing enterprises, the adjacent territories are contaminated by upstream tailings dams. The contamination is developed by active seepage of liquid waste through the body of the dams. The authors have analyzed water balance at the Kachkanar Mining and Processing Plant tailings dump (Russia, Ural Region). The company develops vanadium-containing titanium-magnetite iron ores with low ore (15%). This, along with high productivity, has determined the formation of a large number of tailings and significant amount of wastewater. The purpose of the studies is to substantiate the need to manage the seepage discharge process by means of enclosing dams to ensure environmentally safe operation of the tailings dump. The research objectives included field measurements of seepage volumes, their evaluation by computational methods and analysis of anthropogenic geochemical load on natural waters. The obtained results show an increase in seepage discharge volume from 41.91 million m³ (in 2017) to 81.44 million m³ (in 2026) as the height of the dams increases. These losses will lead to water shortages in the enterprise’s water recycling system. Calculation of pollutants in wastewater with the exception of natural component showed the leading role of technogenic factor in the content of Ti (up to 84%), V (up to 96%), Co (up to 86%) and Mo (up to 93%). Increasing the volume of seepage discharge will lead to an increase in natural water pollution within the area. Ecologically efficient management of the enterprise’s water balance is ensured by the use of tailings thickening technology and implementation of closed water supply systems.

Various natural saline and alkaline habitats have recently been widely investigated, but knowledge of anthropogenic habitats with more complex environmental conditions is still lacking. This research looks at the structure of microbial communities in 18 bottom sediment samples from a technogenic water body with saline and alkaline composition. The core samples were collected from 2 columns in the western and eastern parts of an artificial water body at the Verkhnekamskoe Salt Deposit (Russia). The microbial community structure was studied using high-throughput 16S rRNA gene sequencing. The bottom sediment composition (salinity, pH, and toxic element content) varies greatly with depth and laterally throughout the study area. The study found a considerable difference in bacterial community diversity between the 2 columns, but no considerable difference was found between the communities at various depths of the studied layers. Proteobacteria, Firmicutes, and Actinobacteria, which are common in both natural and artificial saline and alkaline environments, make up the majority of the bacteria found in the samples. Studies have shown that salinity and total alkalinity are the key factors influencing the formation of microbial communities. Ralstonia and Pseudomonas were the two most common genera in the sediment samples. These two genera are known for having high metabolic flexibility, which means they can survive in extreme environments and use a variety of carbon compounds as energy sources. The study also found that Ralstonia is indicator bacteria in samples with the highest concentrations of toxic elements compared to the other samples. A relatively high microbial diversity was discovered in the studied anthropogenic water reservoir despite the extreme alkaline and saline conditions, but it is considerably lower than that found in natural, less alkaline habitats. This research offers insight into the mechanisms behind microbial community formation in complex anthropogenic environments and covers key factors in microbial community distribution.