Influence of Drainage with High Levels of Water-Soluble Salts on the Environment in the Verhnekamskoe Potash Deposit,Russia

Saline drainage from slurry storage facilities can deteriorate the properties of clay barriers in the beds of embankment dams and slurry ponds and cause saline drainage to infiltrate into groundwater. The chemistry of slurry material, drainage, springs, surface water, and soils was studied near the slurry storage facility of the Verhnekamskoe potash mine (Russia). Our study showed that the Na–Cl type mine drainage water, with high amounts of nitrogen compounds, increased the salinity of the groundwater and surface water, and the river valley ecosystems. As a result of ion exchange and leaching, the soil, groundwater, and surface water have elevated levels of \({\text{C}}{{\text{a}}^{2+}}\), \({\text{M}}{{\text{g}}^{2+}}\), \({\text{SO}}_{4}^{{2 - }},\) and \({\text{F}}{{\text{e}}_{{\text{total}}}}\), and extremely high \({\text{~N}}{{\text{a}}^+}\) and \({\text{C}}{{\text{l}}^ - }{\text{~}}\) values. Iron-rich precipitates and hydrogen sulfide tend to form down-gradient in the saline, water-logged seepage areas.     

Biotic and Abiotic Sequestration of Selenium in Anoxic Coal Waste Rock

Mobile selenium oxyanions (\({\text{S}}{{\text{e}}^{{\text{VI}}}}{\text{O}}_{4}^{{2 - }}\) and \({\text{S}}{{\text{e}}^{{\text{IV}}}}{\text{O}}_{3}^{{2 - }}\)) can be sequestered by biotic or abiotic reduction to non-mobile species or by adsorption to mineral surfaces. Microbial analyses and geochemical batch testing with samples collected from a coal waste rock dump in the Elk Valley, British Columbia, Canada were conducted to assess whether Se can be sequestered in anoxic, waste rock by these mechanisms. Bacteria that reduce Se(IV) and Se(VI) to Se(0) were isolated from the waste rock. Isolates that reduce Se(IV) to Se(0) were present in a water sample collected from an underlying rock drain. Three isolates were affiliated with Pseudomonas and Arthrobacter. One isolate was a putatively novel species. The production of Se(0) was confirmed by X-ray absorption near edge spectroscopy of a red precipitate isolated from a broth media containing rock-drain water. No adsorption or reduction of Se(VI) was observed in anoxic, abiotic (sterile) batch tests conducted with waste rock and a 1.0 mg/L Se(VI) solution, whereas Se(IV) was adsorbed by the waste rock and subsequently reduced to Se(0) in abiotic batch tests with a 0.7 mg/L Se(IV) solution. In non-sterile batch tests using waste rock and rock-drain water (0.39 mg/L Se(VI)), Se(VI) was biologically reduced to Se(IV), which was subsequently removed from solution by a combination of bioreduction, adsorption, and possibly abiotic reduction. This study suggests that, under anoxic conditions, Se sequestration in waste rock may occur via biotic reduction of Se(VI) to Se(IV) followed by adsorption of Se(IV) and abiotic and biotic reduction of Se(IV) to Se(0).     

The Hydrogeochemistry of Arsenic in the Clara Mine,Germany

Abstract.   The oxidative dissolution of primary arsenic-bearing sulfide minerals in barite-fluorite veins is a potential source of arsenic in the Clara Mine. Geological structures, especially the mineral veins, provide potential pathways for the water. The highest arsenic concentrations are found in ground water within the eastern part of the mine. Arsenic and major ions are positively correlated and provide evidence that arsenic is likely derived locally from the water-vein/water-rock interaction. Geochemical modeling with PHREEQC shows all the arsenate mineral phases to be significantly undersaturated, although secondary arsenate minerals are common in the oxidized part of the deposit. The mine waters plot near the boundary of Fe(OH)₃ and Fe²⁺ in the pH-Eh diagram for the As-Fe-S-H₂O-system. Arsenic occurs as the 5-valent species and . Statistical analysis illustrates a strong association between As, Fe, pH, and HCO₃. Oxidation of the primary As-bearing minerals, such as pyrite and arsenopyrite, and the subsequent behavior of the oxyanion, arsenate, generally controls the distribution and speciation of arsenic. The low concentrations of dissolved As is due to co-precipitation and adsorption of arsenate by Fe, Al, and Mn (oxy)hydroxides.     

Assessment of Soil and Water Contamination at the Tab-Simco Coal Mine: A Case Study

In 1996, the Tab-Simco site, an abandoned coal mine 10 km southeast of Carbondale, Illinois, was listed as one of the most highly contaminated AMD sites in the mid-continent region. A suite of impacted soil and water samples were collected from various locations to characterize the current extent of AMD pollution, following standard U.S. EPA protocols. The mean pH of soil and water samples were found to be 2.69 and 2.07, respectively. The mean sulfur content of the soil samples was 0.5 %. The AMD-impacted soils contained high concentrations of Fe, Zn, Ni, Cr, Cu, Pb, and As. The AMD also contained high concentrations of Fe, As, Zn, Pb, Cr, Al, Cd, Cu, and Ni, as well as \({\text{SO}}_{4}^{2 - }\), all of which were significantly above their U.S. EPA permissible limits for surface water.     

Hydrogeochemistry and Contamination of Trace Elements in Cu-Porphyry Mine Tailings: A Case Study from the Sarcheshmeh Mine,SE Iran

Geochemical and hydrochemical investigations were performed to understand the contamination potential of the Sarcheshmeh mine tailings. The geochemical mobility for the tailings is as follows: Cu > Cd > Co > Zn > Ni > Mn > S > Cr > Sn > As > Se > Fe = Bi > Sb = Pb = Mo. Highly mobile and contaminant elements (Cd, Cu, Zn, Mn, Co, Ni, S, and Cr), which significantly correlated with each other, were mainly concentrated in the surface evaporative layer of the old, weathered tailings, due to the high evaporation rate, which causes subsurface water to migrate upward via capillary action. The contamination potential associated with the tailings is controlled by: (1) dissolution of secondary evaporative soluble phases, especially after rainfall on the old weathered tailings, accompanied by low pH and high contamination loads of Al, Cd, Co, Mg, Cr, Cu, Mn, Ni, S, Se, and Zn; (2) processing of the Cu-porphyry ore under alkaline conditions, which is responsible for the high Mo (mean of 2.55 mg/L) and very low values of other contaminants in fresh tailings in the decantation pond; (3) low mobility of As, Fe, Pb, Sb, Mo, and Sn due to natural adsorption and co-precipitation in the tailings oxidizing zone. Speciation modeling showed that sulfate complexes (MSO₄ ⁺, M(SO₄)_(aq), M(SO₄) ₂ ^?2 , and M(SO₄) ₂ ^? ) and free metal species (M⁺² and M⁺³) are the dominant forms of dissolved cations in the acidic waters associated with the weathered tailings. In the alkaline and highly alkaline waters, trace element speciation was controlled by various hydroxide complexes, such as M(OH)⁺, M(OH) ₃ ^? , M₃(OH) ₄ ⁺² , M₂(OH) ₃ ⁺ , M(OH)_2(aq), M(OH) ₄ ^?2 , Me(OH) ₂ ⁺ , Me(OH) ₄ ^? , Me(OH) ₂ ⁺ , Me(OH)_3(aq), and Me(OH) ₄ ^? (where M represents bivalent and Me represents trivalent cations). The speciation pattern of As, Mo, and Se is mainly dominated by oxy-anion forms. The obtained results can be used as a basis for environmental management of the Cu-porphyry mine tailings.     

Geomechanical conditions for quasi-resonances in geomaterials and block media

Conclusions  Based on voluminous information about relations between the dimensions of the central zones of crustal earthquakes and various energy classes of underground explosions, as well as mine shocks and man-induced tremors, therefore, the hypothesis that we had previously advanced relative to the quasi-resonant mechanism of their manifestation is confirmed. Here, the geomechanical conditions for the development of quasi-resonances associated with the inducement of pendulum waves are characterized by the dimensionless energy criterion k:

Virtual prototype simulation of hydraulic shovel kinematics for spatial characterization in surface mining operations

Hydraulic shovels are large-capacity equipment for excavating and loading dump trucks in constrained surface mining environments. Kinematics simulation of such equipment allows mine planning engineers to plan, design and control their spatial environments to achieve operating safety and efficiency. In this study, a hydraulic shovel was modelled as a mechanical manipulator with five degrees of freedom comprising the crawler, upper, boom, stick, bucket and bucket door components. The model was captured in a schematic diagram consisting of a six-bar linkage using the symbolic notation of Denavit and Hartenberg (Ho and Sriwattanathmma 1989 Ho, C. Y. and Sriwattanathmma, J. 1989. Robot Kinematics Symbolic Automation and Numerical Synthesis, Norwood, NJ: Ablex.  [Google Scholar]). Homogeneous transformation matrices were used to capture the spatial configuration between adjacent links. The forward kinematics method was used to formulate the kinematics equations by attaching Cartesian coordinates to the schematic shovel diagram. Based on the kinematics model, a 3D virtual prototype of the hydraulic shovel was built in the Automatic Dynamic Analysis of Mechanical Systems (ADAMS) environment to simulate the motions of the hydraulic shovel with selected time steps. The simulator was validated using real-world data with animation and numerical analysis of the digging, swinging and dumping motions of the shovel machinery. The superimposed display of the deployment of the hydraulic shovel in three phases allows a detailed motion examination of the system. The numerical results of linear and angular displacements of the bucket tip and bucket door can be used to analyse the kinematics motion of the hydraulic shovel for its optimization. This simulator provides a solid foundation for further dynamics modelling and dynamic hydraulic shovel performance studies.     

Water quality variation of mining-subsidence lake during the initial stage: cases study of Zhangji and Guqiao Mines

Four quarters?? water collecting and monitoring samples were done in the mining subsidence lakes of different water storing periods (2 to 7 years), considering the water storing time and pollution sources state of the subsidence lakes. The following indexes were discussed such as organic indexes (TOC, COD_Mn, BOD, COD), nutrient salts (TN, NH ₄ ⁺ , NO ₃ ^? , NO ₂ ^? , Kjeldahl Nitrogen, TP, PO ₄ ^3? ), etc. It is shown that water quality of the mining subsidence lake during the initial stage (2 years to 7 years) can stay relatively stable with a fluctuation during different quarters in a year, which can reach class III or IV of the Surface Water Environmental Quality Standard.     

Geochemical and Mineralogical Characterization of a Pyritic Waste Pile at the Anjir Tangeh Coal Washing Plant, Zirab, Northern Iran

Coal washing at the Anjir Tangeh plant, in Zirab, northern Iran, has produced more than 1.5 Mt of coal wastes. These waste materials were geochemically and mineralogically characterised to guide development of an appropriate remediation scheme. Three vertical trenches up to 4 m deep were excavated from the coal waste pile surface and 25 solid samples were collected at 0.5 m intervals. The samples were analysed for total concentrations of 54 elements, paste pH, SO ₄ ^?2 , CO ₃ ^?2 , and HCO₃ ^?. The lowest pH values were measured at a depth of 0.3 m. The upper portion (1 m) of one profile was moderately oxidised, while oxidation in the other two profiles did not extend more than 0.8 and 0.5 m beneath the pile surface. The waste piles have low acid-producing potential (15–21.87 kg CaCO₃/t) and high values of acid-neutralizing potential (0.06–96.2 kg CaCO₃/t). Fe, Al, S, Na, Mn, Pb, Zn, Cd, and Ag increased with increasing depth, while Mo, Sr, Zr, and Ni decreased with increasing depth. The results show pyrite oxidation at depth and subsequent leaching of the oxidation products. Mn, Zn, Cu, Pb, Ag, and Cd are the most important contaminants of concern at this site.     

Mathematical modelling for estimation of minewater inflow to a surface mining operation

Estimation of water inflow to a surface mining operation is a necessary requirement for mine drainage design. The water in a shallow surface mine may originate solely from a surface source and from the atmosphere in the form of precipitation. Water in deep mining excavations below the groundwater table may originate from a surface source or as atmospheric precipitation as well as from the groundwater system. Inflow of surface water to a mining excavation can be predicted by hydrological balance investigation of a mining catchment. The paper briefly describes the hydrological cycle of a mining catchment together with the technique of estimating inflow from a surface source. The groundwater inflow to a mining excavation is mainly a consequence of the interaction of groundwater system, hydrogeological characteristics of the rock mass and the mining geometry. The water inflow regime is determined by the incision of one or more aquifers by the mining excavation and the relative hydrogeological characteristics of the various aquifers. The paper identifies various possible flow regimes in the vicinity of mining excavation. The groundwater inflow can be estimated by one of the following techniques:

- Equivalent flow approach

- Two-dimensional flow equations

- Numerical techniques incorporating the Finite Element Method, Finite Difference Method or the Boundary Element Method.

     

Origin of nitrogen compounds in water infiltrating into porphyry quarry,Zalas, southern Poland.

The paper deals with the problem of the origin of nitric compounds in the mine water entering porphyry quarry. A hydrogeological study of the natural and disturbed ground water regimes as a consequence of quarrying have shown that fecal and domestic sewage was the main source of nitrogen compounds in the water entering the porphyry quarry. The sewage contaminated the surface water which in turn infiltrated into the porphyry within the cone of depression. In addition to that, NH ₄ ⁺ and NO ₃ ^? ions penetrated into the surface water as the result of washing of nitrogen out of the soil and a pa product of biochemical and chemical changes in the soil. A solution of unburnt explosives, used for the ground excavation was also a source of nitrogen compounds.     

Evaluation of pH Testing Methods for Sulfidic Mine Waste

Environmental assessment of solid mine waste is required throughout the life of a mine. This has driven the need for tools and practices to understand the current state of net acidity in mine wastes. Rinse and paste pH tests are commonly used in the initial screening of waste to provide a preliminary evaluation of its current net acidity. Such pH tests are particularly useful for assessing the chemistry of first flush waters draining sulfidic rocks and wastes. In this study, we compared nine different pH tests (rinse and paste pH tests as well as soil tests of the International Organization for Standardization ISO 10390:2005; American Society for Testing and Materials ASTM D4972-01 2007; Standards Australia AS4969.2-2008), using three different sulfidic rock samples and the acid–base accounting standard KZK-1. We observed significant variability in measured pH for the same samples using the different test methods. We show that different rinse and paste pH methods using different grain sizes and extraction solutions can result in different risk classification for ARD assessments. We recommend carrying out pH measurements using 0.01 M CaCl₂ solution, which results in more rapid, reproducible, and precise analyses than using deionised water.     

Unique Pit Lake Created in an Opencast Potassium Salt Mine (Dombrovska Pit Lake in Kalush,Ukraine)

We studied the physicochemical and biological characteristics of the Dombrovska pit lake in Ukraine. The lake formed in an abandoned opencast potassium salt mine and is one of the most saline inland water bodies in the world. It is 85 m deep (November 2015) and an annual inflow of about 2 Mm³ of water. The lake has two distinct layers. The mesohaline surface (0–5 m) layer is well oxygenated and slightly alkaline (pH?=?7.5–8.8). Its mineralization, expressed as dry mass, was 50–134 g dm^??3, and its electrical conductivity (EC) was 58–134 mS cm^??1. The underlying layer consists of hypersaline water with low amounts of dissolved oxygen, a neutral pH (6.7–7.4), high mineralization (179–420 g dm^??3), high EC (169–215 mS cm^??1), and higher concentrations of major anions and cations (except Ca²⁺) and nutrients than the overlying water. The vertical relationship between major ions and metals and the future salinity of the lake are discussed. In terms of zooplankton, in July we found living specimens of the rotifer Brachionus plicatilis and the ciliates Paradileptus elephantinus and Tindinnidium sp. as well as dead rotifers, cladocerans, and copepods (in total, 19 species), but only live B. plicatilis and 9 dead species in November. In the littoral part of the pit lake, we found the diatoms Nitzschia pusilla and some Halamphora species (H. borealis, H. tenerrima, H. acutiuscula), which favour highly saline waters.     

Whitefish (<Emphasis Type="Italic">Coregonus lavaretus</Emphasis>) Response to Varying Potassium and Sodium Concentrations: A Model of Mining Water Toxic Response

Boreal waters are typically low in minerals and oligotrophic, and therefore particularly sensitive to changes in mineral composition. We investigated the effects of potassium and the potassium: sodium (K⁺: Na⁺) ratio in freshwater on growth performance and oxidative stress in a typical northern species of whitefish, Coregonus lavaretus. Fish were subjected to 0.8 mM Na and 4.4 mM K, which corresponds to the K⁺:Na⁺ ratio in a lake contaminated by mining wastes from the Kostomuksha iron mine and ore dressing mill in northwestern Russia. The control group was subjected to water with similar mineralization levels and equal amounts of Na and K (approximately 0.3 mM of each). Potassium excess caused a decrease in fish growth rate and oxidative stress, as indicated by the level of lipid peroxidation product malondialdehyde (MDA). Glutathione-S-transferase (GST) activity and the level of reduced glutathione (GSH) were not affected by cation composition.     

Hydrochemical Characteristics and Groundwater Source Identification of a Multiple Aquifer System in a Coal Mine

Hydrochemical analysis and Bayesian discrimination were used to identify groundwater sources for multiple aquifers in the Panyi Coal Mine, Anhui, China. The results showed that the Cenozoic top aquifer water were HCO₃?Na+K?Ca and HCO₃?Na+K?Mg types, which distinguished it from the other aquifers due to its low Na⁺?+?K⁺ and Cl^? concentrations. The Cenozoic middle and Cenozoic bottom aquifer waters were mainly Cl?Na+K and SO₄?Cl?Na+K types. The water types in the Permian fractured aquifer changed from Cl?Na+K to HCO₃?Cl?Na+K and HCO₃?Na+K moving away from the Panji anticline. In addition, HCO₃ ^? concentrations increased and Ca²⁺ concentrations decreased with depth in the aquifer. The Taiyuan limestone aquifers were of Cl?Na+K, SO₄·Cl?Na+K, and HCO₃·Cl?Na+K types, and are very difficult to distinguish from the other aquifers. The precision of the Bayesian discrimination based on groundwater chemistry was 86.09%. Water chemistry indicators in the Permian fractured aquifer were moderately to highly variable and moderately to strongly correlated, spatially. The water chemistry spatial distribution indicates that the Permian fractured aquifer is recharged by the Cenozoic bottom aquifer near the Panji anticline, which reduces the accuracy of Bayesian discrimination in that area.     

Hydrogeochemical Evolution of an Ordovician Limestone Aquifer Influenced by Coal Mining: A Case Study in the Hancheng Mining Area,China

Statistical analysis was used to study the hydrogeochemical evolution of an Ordovician limestone aquifer group in the Hancheng mining area. Before mining, the groundwater flowed from northwest to southeast, the water type was primarily SO₄–HCO₃, and was mainly controlled by the tectonic structure and the specific hydrogeological conditions. After 40 years of mining, two large groundwater depression cones had formed, centered on the Sangshuping and Xiangshan coal mines in the north and south zones, respectively. The groundwater dropped by ≈?20 m in the center of the depression cones due to over-exploration and mine water inrush, which changed the groundwater flow field significantly. Both the total dissolved solids and the concentrations of major ions increased 2.3- to 4.7-fold, and the water type changed to SO₄–Cl. The saturation indices (SI) of the minerals along the two simulated paths both increased, indicating that the groundwater would dissolve minerals as it flowed, which verified the groundwater flow field. Groundwater quality deteriorated due to a mixture of old acidic pit water and hypersaline water intruding from the deep district. When studied vertically, the concentrations of major ions and SI of calcite and limestone increased, due to the limited cycling of water from shallow to deep. The coincidental Ca²⁺ and Mg²⁺ increases were caused by calcite-replacing dolomitization reactions. To summarize, long-term coal mining adversely affected the area’s groundwater flow field and hydrogeochemical evolution, and effective action should be taken to prevent the Ordovician groundwater from continuing to deteriorate.     

Rotifer Diversity in the Acidic Pyrite Mine Pit Lakes in the Sudety Mountains (Poland)

The diversity of rotifers was studied in three artificial water bodies (Azure Lake, Yellow Lake, and Purple Lake), which were once pyrite mines. The physicochemical parameters and the zooplankton composition of the water were determined. Azure Lake had a pH of 3.4–6.9, conductivity values of 165–194 µS cm^??1, and low concentrations of sulphate, calcium, magnesium, copper, and iron, while the other lakes had a pH of 2.6–2.9, a conductivity of 1636–3400 µS cm^??1, and high concentrations of sulphate (up to 2863 mg dm^??3), Cu (up to 2650 µg dm^??3), and Fe (up to 178.3 mg dm^??3). The rotifer community in the lakes comprised 27 taxa (15 in Azure Lake, 13 in Purple Lake and 14 in Yellow Lake). We also found two species that are rarely observed in Poland (Aspelta cincinator and Elosa spinifera), and three species commonly found in acidic water (E. worallii, Cephalodella delicata, and C. hoodi). The types of rotifers in Azure Lake differed from those in the other two lakes. The Shannon–Weaver biodiversity index (H′) was the highest in Purple Lake (H′?=?1.255) and lowest in Azure Lake (H′?=?0.455). The effect of some of the physicochemical parameters on rotifer diversity is discussed.     

Geochemistry,Hydraulic Connectivity and Quality Appraisal of Multilayered Groundwater in the Hongdunzi Coal Mine,Northwest China

This study assessed the geochemistry and quality of groundwater in the Hongdunzi coal mining area in northwest China and investigated the mechanisms governing its hydrogeochemistry and the hydraulic connectivity between adjacent aquifers. Thirty-four groundwater samples were collected for physicochemical analyses and bivariate analyses were used to investigate groundwater quality evolution. The groundwater in the mine was determined to be neutral to slightly alkaline, with high levels of salinity and hardness; most samples were of SO₄·Cl–Na type. Fluoride and nitrate pollution in the confined aquifers were identified, primarily sourced from coals. Natural geochemical processes, such as mineral dissolution, cation exchange, and groundwater evaporation, largely control groundwater chemistry. Anthropogenic inputs from agricultural and mining activities were also identified in both shallow unconfined aquifers and the deeper confined aquifers, respectively. It was determined that the middle confined aquifer has a high hydraulic connectivity with the lower coal-bearing aquifer due to developed fractures. Careful management of the overlying aquifers is required to avoid mine water inrush geohazards and groundwater quality deterioration. The groundwater in the mining area is generally of poor quality, and is unsuitable for direct human consumption or irrigation. Na⁺, SO₄^2?, Cl^?, F^?, TH, TDS, NO₃^?, and COD_Mn are the major factors responsible for the poor quality of the phreatic water, while Na⁺, SO₄^2?, F^?, and TDS are the major constituents affecting the confined groundwater quality. This study is beneficial for understanding the impacts of coal mine development on groundwater quality, and safeguarding sustainable mining in arid areas.