Saline Mine Water Research Articles

Saline mine water influences eukaryote life in shallow groundwater of a tropical sandy stream

Eukaryotic communities in groundwater may be particularly sensitive to disturbance because they are adapted to stable environmental conditions and often have narrow spatial distributions. Traditional methods for characterising these communities, focussing on groundwater-inhabiting macro- and meiofauna (stygofauna), are challenging because of limited taxonomic knowledge and expertise (particularly in less-explored regions), and the time and expense of morphological identification. The primary objective of this study was to evaluate the vulnerability of eukaryote communities in shallow groundwater to mine water discharge containing elevated concentrations of magnesium (Mg) and sulfate (SO4). The study was undertaken in a shallow sand bed aquifer within a wet-dry tropical setting. The aquifer, featuring a saline mine water gradient primarily composed of elevated Mg and SO4, was sampled from piezometers in the creek channel upstream and downstream of the mine water influence during the dry season when only subsurface water flow was present. Groundwater communities were characterised using both morphological assessments of stygofauna from net samples and environmental DNA (eDNA) targeting the 18S rDNA and COI mtDNA genes. eDNA data revealed significant shifts in community composition in response to mine waters, contrasting with findings from traditional morphological composition data. Changes in communities determined using eDNA data were notably associated with concentrations of SO42−, Mg2+ and Na+, and water levels in the piezometers. This underscores the importance of incorporating molecular approaches in impact assessments, as relying solely on traditional stygofauna sampling methods in similar environments may lead to inaccurate conclusions about the responses of the assemblage to studied impacts.

Improving the Performance of a Salt Production Plant by Using Nanofiltration as a Pretreatment.

The Dębieńsko plant in Czerwionka-Leszczyny, Poland, producing evaporated salt from the saline mine water, faces increasing operating costs due to its high energy consumption. To improve the performance of the plant, a two-pass nanofiltration with intermediate crystallization of gypsum was proposed as a pretreatment. Based on the results of pilot-scale research, it was found that the removal of most of the calcium, magnesium, and sulfate allows a substantial reduction in the concentration of these components in the concentrated brine, which is then directed to a sodium chloride crystallization evaporator. This makes it possible to increase salt yield from the current 58.8% to 76.1% and indirectly reduce energy consumption from 1350 kWh/t to 1068 kWh/t. At the same time, the volume of the highly saline post-crystallization lyes is decreased by 66%, and a new stream is obtained: a Mg-rich solution, which could be used for magnesium hydroxide recovery.

Influence of calcium on the toxicity of saline solutions to the mayfly,

Context Although calcium may provide a means to reduce toxicity of saline waters, the relationship between them is not well understood. Aim To investigate whether increasing calcium may result in a proportional reduction in toxicity. Methods Acute toxicity tests were conducted using an artificial mine-affected water (AMW) and the same AMW with increased calcium on the mayfly species, Austrophlebioides sp. AV11. Results Results demonstrated that there was a reduction in toxicity when calcium concentration (added as both calcium chloride and calcium sulfate together) was increased by both two-fold (+143 mg L−1) and four-fold (+272 mg L−1) compared with the AMW test solution (161 mg L−1). A further increase by up to eight-fold (+718 mg L−1) did not substantially change the toxicity of the AMW solution. Conclusion The toxicity did not reduce when calcium chloride and calcium sulfate salts were used independently. This study suggests that adding calcium (as calcium chloride and calcium sulfate) to a saline solution reduces toxicity upto a maximum threshold, beyond which no further benefit is achieved. Implications Increased calcium can have diminishing effect on toxicity or reach a maximum threshold beyond which no further reduction in toxicity is achieved. Improved understanding of this relationship is needed to inform the management of saline mine waters.

The impact of saline mine water on fate of mineral elements and organic matter: The case study of the Upper Silesian Coal Basin

The work presented here provides a complex environmental impact of sediments in vicinity to the area of the former Lazy coal mine site in the Upper Silesian Coal Basin (Czech Republic). The main aim of this work has been to determine the degree of contamination, to describe the organic matter, and to carry out sorption isotherms to see the size and distribution of pores in the monitored sediments that are the crucial parameters to assumption of removal mechanisms of elements carried in mine water. The results show that the greatest enrichment of Mn, Sr, Ba, and was in sediments of the first tens of meters from the mine water discharge sediments. Ba and Sr were precipitated as mineral barite and thus formed a dominant insoluble component in the river sediments, which were further carried by water flow towards the water reservoirs. Predominant amounts of fossil material and smaller quantities of carbonized and recent organic matter were altered by weathering and erosion processes. The coal materials have a relatively beneficial sorption capacity, which increases with the carbon content. The overburden waste should be considered for use in removing heavy metals in-situ.

First record of the alien aquatic oligochaete species Monopylephorus limosus (Hatai, 1898) (Annelida) in Central Europe

Abstract The paper reports on the first record of the Asian aquatic oligochaete species Monopylephorus limosus (Hatai, 1898) in Central Europe. The species was found in the lower course of the Bolina River (S Poland), which is contaminated with saline mine waters. One immature individual was collected in the late summer of 2017. M. limosus co-occurred with Paranais litoralis, Nais elinguis and juvenile Enchytraeidae. To date, M. limosus is one of the 29 non-native annelids that are known to occur in Poland.

Waste water discharge from a large Ni-Zn open cast mine degrades benthic integrity of Lake Nuasjärvi (Finland)

The Talvivaara/Terrafame multi-metal mining company is Europe’s largest nickel open cast mine, it is also known for the largest wastewater leakage in the Finnish mining history and a series of other accidents. In this paleolimnological study, influences of a recently constructed treated waste water discharge pipeline into Lake Nuasjärvi were investigated by analyzing past (pre-disturbance) and present community compositions of key aquatic organism groups, including diatoms, Cladocera and Chironomidae, along spatial (distance, water depth) gradients. In addition to defining ecological changes and impacts of saline mine waters in the lake, chironomids were used to quantitatively reconstruct bottom water oxygen conditions before and after the pipe installation (in 2015). The diatom and cladoceran communities, which reflect more the open-water habitat, showed only relatively minor changes throughout the lake, but a general decrease in diversity was observed within both groups. Chironomids, which live on substrates, showed more significant changes, including complete faunal turnovers and deteriorated benthic quality, especially at the sites close to the pipe outlet, where also chironomid diversity was almost completely lost. Furthermore, the reconstructed hypolimnetic oxygen values indicated a major oxygen decline and even anoxia at the sites near the pipe outlet. The limnoecological influence of the pipe decreased at sites located counter-flow or behind underwater barriers suggesting that the waste waters currently have location-specific impacts. Our study clearly demonstrates that whereas the upper water layers appear to have generally maintained their previous state, the deep-water layers close to the pipe outlet have lost their ecological integrity. Furthermore, the current hypolimnetic anoxia close to the pipe indicates enhanced lake stratification caused by the salinated mine waters. This study clearly exhibits the need to investigate different water bodies at several trophic levels in a spatiotemporal context to be able to reliably assess limnoecological impacts of mining.

Post operation inactivation of acidophilic bioleaching microorganisms using natural chloride-rich mine water

The H2020 BIOMOre project (www.biomore.info, Grant Agreement #642456) tests the feasibility of in situ bioleaching of copper in deep subsurface deposits in the Rudna mine, Poland. Copper is leached using biologically produced ferric iron solution, which is recycled back to the in situ reactor after re-oxidation by iron-oxidizing microorganisms. From a post operational point of view, it is important that the biological processes applied during the operation can be controlled and terminated. Our goal was to determine the possibility to use natural saline mine water for the inactivation of the introduced iron-oxidizing microorganisms remaining in the in situ reactor after completion of the leaching process of the ore block. Aerobic and anaerobic microcosms containing acid-leached (pH 2) sandstone or black shale from the Kupferschiefer in the Rudna mine were further leached with the effluent from a ferric iron generating bioreactor at 30 °C for 10 days to simulate the in situ leaching process. After the removal of the iron solution, residing iron-oxidizing microorganisms were inactivated by filling the microcosms with chloride-rich water (65 g L−1 Cl‐) originating from the mine. The chloride-rich water irreversibly inactivated the iron-oxidizing microorganisms and showed that the naturally occurring saline water of the mine can be used for long-term post process inactivation of bioleaching microorganisms

An Overview of Priority Pollutants in Selected Coal Mine Discharges in Europe

Coal mine discharges in several European countries were investigated as part of the European Commission’s MANAGER project. The emphasis of the project was identification of priority pollutants and potential remedial approaches. The main identified priority pollutants were sulphate (all countries) and iron (all countries except Greece). High concentrations of chloride (particularly in Germany and Poland) were associated with discharge of saline mine waters linked to the presence of fossil sea water; these mine waters also had high boron concentrations, in contrast to chloride-rich waters in UK that are linked to recent sea water inflow. Concentrations of trace metals vary among countries, but radium is an important contaminant in barium-rich waters with low sulphate concentrations, essentially in Poland. Concentrations of trace metals and metalloids were generally low because of their relative scarcity in coal strata and adsorption onto ferric oxides and hydroxides, but they still often exceeded the environmental quality thresholds.

Impact of a Saline Mine Water Discharge on the Development of a Meromictic Pond, the Rontok Wielki Reservoir, Poland

A characteristic feature of the mines in the Upper Silesian Coal Basin in southern Poland is their highly saline mine water. In the past, this water was often discharged into anthropogenic reservoirs located a short distance from the mines, which completely changed the physicochemical properties of the water. In some cases, it also led to stratification of the reservoir waters, i.e. to the formation of meromictic water bodies. The Rontok Wielki reservoir, a former fish breeding pond, was converted into a settling tank for the highly saline (Cl− = 38,000 mg/L) water discharging from the Silesia Mine. The water in the tank stratified in three distinct zones: a mixolimnion, chemocline, and monolimnion. The saline mine water input ceased in 2003 and since then, there has been a gradual decrease in the electrical conductivity and [Cl−] in the reservoir waters. Moreover, meromixis has been entirely eliminated and freshwater breeding species have reappeared. A control, the Rontok reservoir, which was also a breeding pond, but was never used to settle saline mine water, was also studied for comparison.

Macroinvertebrate communities on various microhabitats of a saline coal mine settling pond

Abstract To date, no studies have been conducted on macroinvertebrate communities in coal mine settling ponds used for temporary retention of saline mine waters. The objective of the research was to evaluate which habitat – Ruppia maritima, Phragmites australis or sediments without macrophytes – is the most favorable for the abundance and biomass of macroinvertebrate communities. The study was carried out in a hyposaline settling pond located in a mining and urban area in southern Poland. At this time, it is the only inland locality of R. maritima in Poland. In the studied coal mine settling pond, the non-native, euryhaline amphipod Gammarus tigrinus dominated in the communities on all the habitats. The abundance of other taxa was small and similar on each type of substrate; only Corixidae were much more abundant on the widgeongrass beds. The highest abundance and biomass of macroinvertebrates was recorded at the sites with R. maritima. Our study highlights the importance of coal mine settling ponds as a substitute habitat for salt-tolerant invertebrates.

Geotouristic attractions of the Ostrava part of the Upper Silesian Basin: geological and environmental sites

Abstract In the Ostrava part of the Upper Silesian Basin there are many geotouristic sites connected with the underground mining of Carboniferous bituminous coal. Text is focused on those related to the geology of the Basin and environmental issues connected to coal mining. Of great intrest are outcrops of Mississippian sediments of the paralic Ostrava Formation, as well as two most important museums with permanent geological exhibitions. Some interesting geological features conncted to younger periods of Quarternary glaciation are also mentioned. Two types of publicly accessible sites related to the environmental burdens (burning coal heaps, saline mine water drainage system) are also described.

Multiple mining impacts induce widespread changes in ecosystem dynamics in a boreal lake

In order to satisfy the needs of constant economic growth, the pressure to exploit natural resources has increased. Since accessible mineral resources are becoming scarce, the mining industry is constantly looking for novel techniques to allow commercial exploitation of lower-grade deposits. However, mining can have considerable impacts on freshwater ecosystems. Here, we present the ecological damage inflicted by mine water originating from the massive Terrafame Talvivaara polymetal mine (central Finland), where bioheap leaching is being applied to high-sulphur low-grade ore. We found that saline mine water has turned the lake meromictic, and sediment is heavily contaminated. As a result, important zooplankton and phytoplankton groups have been significantly altered. As the exploitation of poor-grade deposits is the future of the mining industry globally, water management should be taken to a higher level in order to proceed towards a sustainable mining sector.

Evaluation of Long-Term Post Process Inactivation of Bioleaching Microorganisms

The H2020 BioMOre project (www.biomore.info, Grant Agreement #642456) tests the feasibility of in-situ bioleaching of copper in deep subsurface deposits in the Rudna Mine, Poland. Copper is leached using biologically produced ferric iron solution, which is recycled back to the in-situ reactor after re-oxidation by iron-oxidizing bacteria (IOB). From a post operational point of view, it is important that the biological processes applied during the operation can be controlled and terminated. Our goal was to determine the possibility to use natural saline mine water for the inactivation of introduced IOB remaining in the in-situ reactor after completion of the leaching process of the Kupferschiefer ore. Aerobic and anaerobic microcosms containing acid-leached (pH 2) sandstone or black shale from the Kupferschiefer in the Rudna mine were further leached with the effluent from an iron-oxidizing bioreactor, at a temperature of 30°C, for 10 days, to simulate in-situ leaching. After the removal of the iron solution, residing IOB were inactivated by filling the microcosms with saline water (65 g L-1 Cl-) originating from the mine. The saline water completely inactivated the IOB and the naturally occurring saline water of the mine can be used for long-term post process inactivation of bioleaching microorganisms.

Mine emissions reduction installations

This paper presents two installation concepts intended to reduce emissions in hard coal mines: emissions of the gas which is high in methane from methane capture process, emissions of the ventilation air which is low in methane, and emissions of the saline mine water. In one concept, the heat from gas combustion in the ventilation air is used to generate superheated steam in a local steam boiler. The superheated steam in a turbine set with a backpressure turbine generates electricity, and the backpressure steam flows into a multi-stage evaporation station where it is used for desalination of portions of mine water. In the second concept, the stream of gas with a high content of methane is supplemented with hard coal in order to utilise the entire stream of mine water. Mathematical models of the component balance of heat and mass are developed for both installations, and calculations are performed using real emissions data from a selected coal mine. Results are shown in mass flow and energy flux Sankey diagrams. We find that full utilisation of the high-methane gas reduces emissions of mine ventilation air by 2.5% and of the saline mine water by 21%. Also, co-firing with supplementary coal ensures a 100% desalination of the mine water and 10% utilisation of the ventilation air.An approximate estimate of the economic evaluation and a sensitivity analysis are also presented for both concepts. Results indicate that the first concept is more profitable than the second concept. This is because the payback period (PP) is shorter (7.67 and 9.67 years, respectively), and the rate of return based on cash flows (ARRCF) is greater (13.03 and 10.36%, respectively) at an unchanged load factor of 90% and a 10-year life cycle. Also, the first concept is found to be significantly less risky. Technical and economic analysis of the proposed solutions shows that both solutions are useful; therefore, the most suitable solution should be chosen based on other conditions such as indicators of state environmental policy.

Identifying the cause of toxicity of a saline mine water.

Elevated major ions (or salinity) are recognised as being a key contributor to the toxicity of many mine waste waters but the complex interactions between the major ions and large inter-species variability in response to salinity, make it difficult to relate toxicity to causal factors. This study aimed to determine if the toxicity of a typical saline seepage water was solely due to its major ion constituents; and determine which major ions were the leading contributors to the toxicity. Standardised toxicity tests using two tropical freshwater species Chlorella sp. (alga) and Moinodaphnia macleayi (cladoceran) were used to compare the toxicity of 1) mine and synthetic seepage water; 2) key major ions (e.g. Na, Cl, SO4 and HCO3); 3) synthetic seepage water that were modified by excluding key major ions. For Chlorella sp., the toxicity of the seepage water was not solely due to its major ion concentrations because there were differences in effects caused by the mine seepage and synthetic seepage. However, for M. macleayi this hypothesis was supported because similar effects caused by mine seepage and synthetic seepage. Sulfate was identified as a major ion that could predict the toxicity of the synthetic waters, which might be expected as it was the dominant major ion in the seepage water. However, sulfate was not the primary cause of toxicity in the seepage water and electrical conductivity was a better predictor of effects. Ultimately, the results show that specific major ions do not clearly drive the toxicity of saline seepage waters and the effects are probably due to the electrical conductivity of the mine waste waters.

Impact of Saline Mine Water: Development of a Meromictic Reservoir in Poland

The hard coal mines in the Upper Silesian Coal Basin of southern Poland have highly saline waste water. In the past, such water was often discharged into nearby res- ervoirs, which would completely change the physical- chemical properties of the reservoir water. In some cases, it also caused permanent stratification; meromictic reservoirs were created. This paper describes the properties of the water in one such reservoir, in a mined out rock quarry in Katowice (southern Poland). Three zones characteristic of meromictic water bodies can be distinguished in the reservoir: a surface atmosphere responsive zone (mixolimnion), a transition zone (chemocline), and a bottom unmixed layer (monolim- nion). For comparison, baseline conditions for normal res- ervoir water were assumed to be represented by the nearby Grunfeld reservoir, which also formed in a closed quarry, but was not used for disposal of mine waste water.

Assessment of the Impact of Irrigation with Low-quality Mine Water on Virgin and Rehabilitated Soils in the Upper Olifants Basin

Low-quality mine water from collieries may be used in large quantities to irrigate agricultural crops on virgin (unmined) and rehabilitated soils in South Africa. Such a use could enhance crop production and allow environmentally sustainable mine water disposal. In this study, the volume and qualities of the runoff from two centre pivots irrigated with moderately saline mine water, as well as their soil water salinities, were monitored and used to determine water and salt balances, using the modified ACRU agrohydrological model, ACRU2000, and its salinity module, ACRUSalinity. At both sites, much of the water evaporated, while a significant part of the salt input either precipitated or remained with the water in the soil horizons. A higher percentage of drainage water (and salinity) were retained as ground water storage and a lower percentage of runoff occurred in the rehabilitated sandy loam soil, while a higher percentage of salts accompanied runoff in the virgin clayey soils. Simulated salt saturation values indicate that many crops could be successfully irrigated at 100% yield potential at either site. Electrical resistivity surveys were carried out at both sites. A general decrease in resistivities with depth in both the virgin and rehabilitated soils reflected the decreasing influence of the mine water used for irrigation with depth and the precipitation of salts in the soils close to the ground surface. The occurrence of a thicker, low-resistivity, near-surface layer near the exit of each pivot area indicates that the water and salt content of the subsurface increased in the direction that the surface and near-surface irrigation water flowed.

Changes in water quality and runoff in the Upper Oder River Basin

The aim of the study is the analysis of runoff and water quality changes in the Upper Oder River Basin above the Krapkowice gauging station (catchment area A = 10 720.6 km 2). The issue of water quality is of particular importance to Poland, which has comparatively poor water resources compared with many countries of the European Union (EU). What is more, large pollutant loads in the upper course of the Oder pose huge problems for water consumers and users in its middle and lower course (including Germany) and pollute the Baltic Sea. Changes in 7 indices of water pollution, including BOD 5 and COD (synthetic indices), sulphates, chlorides and suspended matter (mineral substances) and nitrates and phosphates (biogenic substances), were investigated for 8 monitoring sites. The study spans the period before and after political transformation in Poland and the Czech Republic, which significantly altered the economies of these countries. In addition, the patterns of runoff changes were analysed at 3 gauging stations: Chałupki, Krzyżanowice and Miedonia, which were also water quality monitoring points. The analysis encompassed 2 periods: 1970–2000 and 1991–2000. The results demonstrated that poor water quality in the Oder improved significantly during the 1990s, as the result of closure of many industries and plants, improvement of sewage treatment and noticeable increases in runoff causing greater dilution of pollutants. As the EU Water Framework Directive is implemented, better water and sewage management can be expected that will contribute to further improvement of water quality in the Oder. However, problems that remain to be solved are the issues of saline mine waters and surface washings and the long-term accumulation of many hazardous substances in bottom sediments in rivers and reservoirs.

Estimating the Unknown Components of Nutrient Mass Balances for Forestry Plantations in Mine Rehabilitation, Upper Hunter Valley, New South Wales, Australia

Commercial forestry plantations as a postmining land use in the Upper Hunter Valley of New South Wales, Australia are restricted by both the poor nutrient availability of mining substrates and low regional rainfall. An experiment was conducted to investigate whether municipal waste products and saline groundwater from coal mining operations could improve early tree growth without impacting on the environment through salt accumulation and/or nutrient enrichment and changes in groundwater quality. Potential impacts were investigated by quantifying the nutrient cycling dynamics within the plantation using an input-output mass balance approach for exchangeable calcium (Ca(2+)), exchangeable magnesium (Mg(2+)), exchangeable potassium (K(+)), exchangeable sodium (Na(+)), nitrogen (N), and phosphorus (P). Measured inputs to and outputs from the available nutrient pool in the 0-30 cm of the overburden subsystem were used to estimate the net effect of unmeasured inputs and outputs (termed "residuals"). Residual values in the mass balance of the irrigated treatments demonstrated large leaching losses of exchangeable Ca, Mg, K, and Na. Between 96% and 103% of Na applied in saline mine-water irrigation was leached below the 0-30-cm soil profile zone. The fate of these salts beyond 30 cm is unknown, but results suggest that irrigation with saline mine water had minimal impact on the substrate to 30 cm over the first 2 years since plantation establishment. Accumulations of N and P were detected for the substrate amendments, suggesting that organic amendments (particularly compost) retained the applied nutrients with very little associated losses, particularly through leaching.

The use of saline mine water and municipal wastes to establish plantations on rehabilitated open-cut coal mines, Upper Hunter Valley NSW, Australia

Commercial forestry plantations as a post-mining land use in the Upper Hunter Valley NSW, Australia, have productivity limitations and are restricted by the poor nutrient quality of mining substrates and low regional rainfall. However, municipal waste products and saline groundwater from coal mining operations can assist in establishing and improving plantation growth rates. The aim of this study was to investigate the establishment and growth of four potentially commercial species in a saline irrigation and nutrient amendment experiment over 2 years. The experiment was designed as a split–split plot with irrigation being the main plot effect, nutrient amendments (overburden, fertiliser, biosolids, compost and topsoil) as the subplot effect and species ( Corymbia maculata Hook, Eucalyptus botryoides Smith, E. tereticornis Smith and E. occidentalis Endl.) as the sub-subplot effect. Survival, height, diameter, above-ground biomass, tree form and weed competition in each treatment were measured along with substrate electrical conductivity. Tree survival after 24 months improved with irrigation (89.8%) compared to the rain-fed treatment (78.6%). Irrigation did not significantly improve tree growth responses but there was an increasing trend after 24 months with irrigation producing better overall growth. Biosolids, compost and fertiliser produced significantly better growth than the topsoil and overburden treatments. However, weed growth was higher in biosolids and compost and was correlated with reduced tree growth but not less than topsoil and overburden treatments. Eucalyptus occidentalis performed significantly better than other species in relation to height (1.89 m), diameter at 30 cm (3.1 cm) and standing crop biomass (982 kg ha −1) after 2 years. Surface substrate EC 1:5 (0–10 cm) increased significantly following irrigation events but reduced over time by leaching from rainfall. Electrical conductivity in the lower horizon (10–30 cm) was not significantly different from the upper horizon in the irrigation treatment but was significantly higher in the rain-fed treatment after 2 years. Biosolids and compost increased EC 1:5 over the first 6 months but thereafter compost and overburden produced higher values during the second year of the study. These results show that saline mine water irrigation can be used to establish plantations without impacting deleteriously on tree growth and substrate EC 1:5. However, further research is required to determine whether growth rates will reach a commercial standard and that the long-term impacts of using saline irrigation water are avoided.