The environmental impact of deposit development can be indirect and can cause combined geochemical processes in ecosystems. These must be taken into consideration under environmental forecasting and environmental risk assessment. Soil degradation in the Taiga Forest is considered, within the area of Verkhnekamskoye potash deposit (Russia), as an example of such environmental transformation. Here, the mechanism and characteristics of the anthropogenic salinisation of alluvial soils under potash deposit development are newly described. It was found that there is a strong anthropogenic impact of the potash industry on valley soils where the contaminated Na-Cl groundwater discharges or is close to the surface. The valley soils are characterised by high salinity, and the sum of toxic salts in soils has reached 26%. Alluvial gley humic clay chloride saline soil (Gleyic Fluvisols (Salic, Loamic, Technic)) and secondary solonchak on alluvial humic clay soil sulphate-chloride gypsum-containing surface-gleyed (Chloridic Gleyic Fluvic Solonchak (Hypersalic, Loamic, Technic)) were formed in hydromorphic conditions. Morphological, physicochemical and mineralogical analyses were carried out. Under hydromorphic conditions, Chloridic Gleyic Fluvic Solonchak (Hypersalic, Loamic) was described to show a hydrotroillite layer and reddish-yellow iron-rich precipitates on its surface. The top soil horizon has the highest content of iron minerals (up to 84.9%) and Fe-bearing plant residues (up to 20%). Additionally, the spongy and gel-like organic materials, as well as the siliceous remains of diatoms, are enriched in Ca, Fe, Cl, K, Na, S and P. The lower soil horizon consists of black gel-like phases and hydrogen sulphide settings with a high content of plant residues. The insoluble part of the samples contains up to 84% hydrogoethite. The sources of iron in soils and bottom sediments include the iron-enriched Sheshma sediments speckled rocks, slurry material, halite wastes and soil minerals of alluvial gley soils.

During the development of coal deposits, acid mine waters flowing to the surface cause the formation of acid sulphate soils. We study the effectiveness of soil reclamation by agrochemical and geochemical methods at the site of acid mine water discharge in the Kizel Coal Basin, carried out in 2005 using alkaline waste from soda production and activated sludge. A technosol with a stable phytocenosis was detected on the reclaimed site, and soddy-podzolic soil buried under the technogenic soil layer with no vegetation on the non-reclaimed site. The buried soddy-podzolic soil retains a strong acid рН concentration Н2О = 3. A high content of organic matter (8-1.5 %) is caused by carbonaceous particles; the presence of sulphide minerals reaches a depth of 40 cm. Technosol has a slightly acid pH reaction H2O = 5.5, the content of organic matter due to the use of activated sludge is 19-65 %, the presence of sulphide minerals reaches a depth of 20-40 cm. The total iron content in the upper layers of the technosol did not change (190-200 g/kg), the excess over the background reaches 15 times. There is no contamination with heavy metals and trace elements, single elevated concentrations of Li, Se, B and V are found.

The change in soil-forming processes and, as a result, in the ecosystem due to nearly 300-year long outflow of highly saline waters from ancient brine wells is considered for Perm Krai in Russia for the first time. The study area is located in the high floodplain of the Usolka River valley. Sodium-chloride ancient brine wells with mineralization of about 30 g/L flow in streams over the soil surface and enter the Usolka River. The paper considers three soil types at various distances from a saline stream. The main pedogenic processes are the sod-forming process and gleying in alluvial soils. Soils in Gleyic Fluvisols (background)—Gleyic Fluvisols (Sulfatic) (transition)—Solonchak (affected by sodium-chloride brines) series were studied in terms of occurring soil-forming processes. All studied soils are formed under hydromorphic conditions. It is evidenced by gleization. However, the morphological and physicochemical properties of the soils differ. The presence of water-soluble ions in the solonchak suggests that salinization is occurring. The sum of toxic salts was 0.94% which was several times higher than in the transition and background soils. The sodium adsorption ratio (SAR) ranged from 10.4 to 21.6, with a рН of 8.3–9.1. The saline soils were more alkaline (pH average 8.8 and 9.3) than the background soil (pH 8.1). SAR decreased significantly in the Solonchak—transition—background soil series from 16.9 to 0.7. The aforementioned observations, as well as physical properties of the saline soil, clearly show the entry of sodium into the solonchak adsorption complex, indicating the solonization process. The study area is characterized by the presence of salt-tolerant species of herbaceous plants and an obligate halophyte. Salicornia perennans Willd, a halophyte, was discovered in the wells’ discharge area at a distance of 0.2–1.5 m from saline streams. The analysis of the long-term impact of highly mineralized waters on the natural environment will aid in revealing and forecasting ecosystem changes caused by potash mining in Perm Krai for environmental risk assessment for new and existing potash enterprises.

Relevance. Related to the need to carry out environmental protection measures in potash mining areas exposed to the environmental consequences of the impact of multi-tonnage salt waste. Aim. To summarise and analyse the geography of potash mining operations, the environmental impact of these operations, and potash waste management practices. Object. Potash mining waste. Methods. Theoretical and logical analysis of the data. Results. The research considers the geographical distribution of potash deposits and presents the characteristics of potash mining waste using the example of the Verkhnekamskoe Potash Deposit. The paper provides both domestic and foreign analyses of ecological consequences of waste storage on the day surface. Several options for potash mining waste management are analysed. For the management of clay-salt slurry, the most effective approach is its injection into underground horizons, which includes the use of saturated solutions as a fertiliser component, as a part of a product in construction, and in the oil industry. A more comprehensive approach to halite waste management is needed. Waste disposal to waste dumps is relevant due to the presence of mined-out areas on the territory of long-operating enterprises. Reclamation of the salt dump will help to isolate it from atmospheric precipitation, thereby reducing the inflow of saturated water into the environment. Utilising waste for production of construction materials is the most economically and environmentally favourable option. Extracting valuable components, producing fertilisers, concentrates, etc. from waste is the least practical approach due to the ecological and economic expenses involved in acquiring extraction equipment and the repeated generation of waste. The most challenging aspect of reducing waste generation in terms of technology lies in improving mining operations and implementing selective mining. Актуальность работы связана с необходимостью проведения природозащитных мероприятий на территории калийных горнодобывающих предприятий, испытывающих экологические последствия влияния многотоннажных солеотходов. Цель исследования заключается в обобщении и анализе географии распространения калийных горнодобывающих предприятий, воздействия этих предприятий на окружающую среду и методов управления отходами калийных производств. Объекты: отходы калийных горнодобывающих предприятий. Методы: теоретический и логический анализ данных. Результаты. Рассмотрена география распространения калийных месторождений и представлена характеристика отходов калийных горнодобывающих предприятий на примере Верхнекамского месторождения солей. Приведен отечественный и зарубежный анализ экологических последствий в результате хранения отходов на дневной поверхности. Проанализировано несколько вариантов обращения с отходами калийных предприятий. При управлении глинисто-солевыми шламами наиболее эффективна закачка в подземные горизонты, в том числе использование насыщенных растворов в качестве удобряющего компонента, составляющей части продукта в строительном направлении и применение в нефтедобывающей отрасли. При управлении галитовыми отходами нужен более комплексный подход. Закладка в отработанное пространство является актуальным подходом в связи с тем, что на территории долго действующих предприятий имеются уже отработанные целики. Рекультивация солеотвала позволит изолировать тело отвала от поступления атмосферных осадков, что приведет к сокращению поступления насыщенных вод в окружающую среду. Использование отходов для производства стройматериалов является наиболее предпочтительным как с экономической, так и с экологической позиции. Извлечение ценных компонентов, производство удобрений, концентрата и др. из отходов является наименее актуальным направлением, это связано как с эколого-экономическими затратами на приобретение оборудования по извлечению, так и с повторным образованием отхода. Наиболее сложным направлением для снижения образования отходов в технологическом аспекте является совершенствование ведения горных работ и селективной добычи.

Chemical and ecological properties of soils and the NDVI analysis on reclaimed sulfide coal waste dumps in the boreal zone

Technogenic soils result from the oxidation and hydrolysis of minerals in rocks extracted from mining areas and brought to the surface. Diagnostics of such soils involve a set of detailed tests, which can be both time-consuming and costly. In this study, the pH of sulfate soils in the Kizel Coal Basin (Perm krai, Russia) was determined using hydrogen peroxide. Particularly, the soils affected by runoff from rock dumps, outflow, and mine water discharge were examined. The findings showed pH-H2O2 below 2.5 in certain horizons, indicating the presence of sulfides. Additionally, the soils exhibited significantly higher levels of mobile sulfur and iron, total sulfur, and sulfates, ranging from tens to hundreds of times above the background content. XRD analysis revealed that the soils contained goethite and jarosite, thereby confirming the efficacy of pH determination with hydrogen peroxide for the prompt diagnostics of acid sulfate soils.