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Article

Flooded Historical Mines of the Pitkäranta Area (Karelia, Russia): Heavy Metal(loid)s in Water

by
Evgeniya Sidkina
1,* and
Artem Konyshev
2
1
Geological Institute, The Russian Academy of Sciences, 119017 Moscow, Russia
2
Institute of Geology, Karelian Research Centre, The Russian Academy of Sciences, 185910 Petrozavodsk, Russia
*
Author to whom correspondence should be addressed.
Water 2025, 17(16), 2418; https://doi.org/10.3390/w17162418
Submission received: 23 July 2025 / Revised: 5 August 2025 / Accepted: 12 August 2025 / Published: 15 August 2025
(This article belongs to the Section Water Quality and Contamination)
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Versions Notes

Abstract

Mining activities have long-term impacts on the environment even after the active stage. Historical mines developed in the 19th and 20th centuries for tin, copper, and mainly iron ore are located in the Pitkäranta area (Karelia, Russia). These objects are considered in our research as natural–anthropogenic sites of long-term water–rock interaction. Waters from flooded mines are the subject of this research. Redox conditions, pH, dissolved oxygen content, conductivity, and water temperature were determined during field work. The chemical composition of natural waters was determined by ICP-MS, ICP-AES, ion chromatography, potentiometric titration, and spectrophotometry. Our investigation showed that the mine waters are fresh and predominantly calcium–magnesium hydrocarbonate; most samples showed elevated sulfate ion contents. Circumneutral pH values and the absence of extremely high concentrations of heavy metals indicate neutral mine drainage. However the calculation of the accumulation coefficient showed the highest levels for siderophile elements relative to the corresponding data of the geochemical regional background. Moreover, zinc has the highest content in the series of heavy metal(loid)s considered. The maximum concentration of zinc was determined in the water of one of the shafts of the Lupikko mine, i.e., 5205 µg/L. The accumulation of heavy metals occurs in the process of long-term interaction of water–rock–organic matter under conductive redox conditions. Overall, the research highlighted the relevance of investigating the geochemistry of historical mines in the Pitkäranta area both from the perspective of environmental safety and the preservation of mining sites for scientific and educational purposes.

1. Introduction

The Pitkäranta area is a unique area with a complex geological setting and rich geochemical variety of rocks [1]. The area contains natural resources of various types: numerous ore occurrences, deposits of building materials, and high-quality natural waters [2,3]. The last of the above determines the relevance of the proposed research. Protection of high-quality natural waters is a critical challenge for global science in the 21st century [4,5]. These problems are especially acute in conditions of anthropogenic impact [6,7].
Anthropogenic impact on the environment is widespread in various regions, one of the most destructive is mining [8]. In our case, the situation is aggravated by the long mining history in the region [9]. Ore deposits developed in the 19th–20th century represent abandoned mines and dumps located in the Pitkäranta District, including directly in the residential area. The majority of technogenic objects do not have an approved status, and, accordingly, monitoring is not established for them. Currently, the mine shafts are flooded, and the waste dumps are stored without any special environmental protection. Numerous studies [10,11,12] have shown that interaction with ore and host rocks containing sulfide mineralization leads to the accumulation of contaminants in waters. In the mining industry, the most harmful to the environment is acid mine drainage, which occurs as a result of the oxidative dissolution of sulfide minerals [13,14]. The acidic drainage is a common occurrence in both active and abandoned mine sites [15,16]. Globally, neutral mine drainage is less common; it occurs most often when acid is neutralized by dissolving carbonate minerals [17,18]. Neutral mine acid drainage attracts less attention because it has a less destructive effect on the environment than acid drainage. However, neutral drainage in mine sites leads to accumulation of heavy metal(loid)s, which, in certain concentrations, can have a negative impact on human health, as well as aquatic species and flora. In addition, in the case of historical mines [19], the duration of water–rock interaction plays a major role in the accumulation of contaminants. In general, the problem of pollution of natural waters in areas of abandoned mines is acute in many regions [20,21,22], but the level of pollution largely depends on many conditions and factors.
The lack of governing management, as well as general environmental awareness in the mine industry of past centuries, led to uncontrolled consequences associated with the spread of potentially toxic elements in the environment, primarily concerning water resources. In the absence of special measures to protect the environment, mine waters enter the hydrographic network of the region and are also drained into aquifers through fractured rocks. Natural waters of the Pitkäranta area are used for drinking and in domestic, industrial, and agricultural activities. In addition, recreational fishing is popular, and there are also fish farms. It is also worth noting that, recently, ecotourism has been gaining popularity in the region.
Our research is the first consistent investigation of the waters of the Pitkäranta area mines. Previously, we conducted geochemical research on several mines in the Pitkäranta area [23,24,25,26], during which it was established that the main contaminants are the following heavy metal(loid)s: Zn, Cd, Ni, Pb, Cu, and As. Based on new data, and also combined with previously obtained conclusions, the aim of this study is to identify patterns of distribution and behavior of heavy metal(loid)s, and discuss the processes and factors of accumulation of these chemical elements in the waters of mine objects.

2. Study Area

2.1. Geological Essay

The geological structure of the research area consists of three material–time rock complexes: (1) AR2-PR1 metasedimentary rocks, (2) Mesoproterozoic intrusive rocks, and (3) Quaternary sediments [27] (Figure 1).
The metamorphic rocks in this area have experienced the maximum degree of metamorphism corresponding to the amphibolite facies [28,29]. At the base of the meta-sedimentary rocks are gneissogranites with lenses and interlayers of meta-amphibolites (AR2-PR1). As a result of the Svecofennian collisional orogeny (1.8 million years), these rocks formed numerous diapirs (gneissogranite domes), which were widely developed in the Northern Ladoga region [30]. In the frame of gneissogranite domes (higher in the stratigraphic section) the rocks of the Sortavala series (PR1, ludikovian) and the youngest rocks of the Ladoga series (PR1, kalevian) are located.
The Sortavala series in the study area is represented by the Pitkäranta suite, which includes two metacarbonate horizons (lower and upper) that are not stable in terms of thickness [31,32], with a sequence of schistated meta-amphibolite between them, sometimes graphite-containing. The metacarbonate horizons are skarnified. According to the data of [33], the terrigenous material of the Sortavala series rocks have a similar age to the gneissogranitic domes.
The lower carbonate horizon of the Sortavala series was formed under conditions of marine transgression and is represented by sediments from shallow, partially isolated paleobasins; the carbonate deposits of the upper horizon were formed in the distal part of an extensive marine paleobasin [34].
The Ladoga series in this area is represented by biotite–quartz, quartz–feldspar–biotite, amphibole, and graphite-containing shists with layers of hornfels and skarnified rocks.
In the Mesoproterozoic, two tectonic–magmatic events occurred that led to the formation of the Salmi anorthosite–rapakivigranite complex and the Valaam sill of gabbro–dolerites.
The Salmi anorthosite–rapakivigranite complex is 1547–1530 million years old [35,36]. In the study area, the complex is represented by three main varieties: biotite–amphibole granites (wiborgites), biotite granites, and topaz-containing leucogranites [1]. Mesoproterozoic granitoids are exposed on the surface east of the town of Pitkäranta; their roof dip toward Lake Ladoga and is located under the meta-sedimentary rocks of the Sortavala series at depths from the first tens to hundreds of meters [37]. As a result of the fluid postmagmatic interaction, metacarbonate rocks acted as a geochemical barrier, which led to their skarnification and the formation of Sn-Fe–rare metal–polymetallic mineralization. Currently, it is widely thought that the main volume of skarns in the study area is associated with acidic rocks of the Salmi anorthosite–rapakivigranite complex. However, some of the molybdenite from skarns was shown to be more ancient than Salmi granites, as they were dated at 250–300 million years older (according to Re-Os), which is interpreted as the beginning of the occurrence of skarn mineralization at the stage of orogeny [1]. Due to the intrusion of the Salmi anorthosite–rapakivigranite rock complex, a zone of increased postmagmatic activity developed along its northwestern border in the form of a narrow strip up to 50 km long and up to 15 km in thickness—known as the Pitkäranta area in Russia («Pitkäranta ore district» in Russian literature).
The Valaam gabbro–dolerite sill has an estimated age of introduction of 1459 ± 3 and 1457 ± 3 million years [38], and it belongs to the high-iron intraplate rocks of the tholeiitic series. The main volume of these rocks is located much to the west of the studied area in the center of Lake Ladoga (Valaam archipelago). However, related to this magmatic event, to the east of Pitkäranta, is a small neck of augitic porphyrites “Hopunvaarsky” has been formed in the area of the southern slope of the hill known as Hopunvaara.
The quaternary sediments of the studied area are represented by boulder–sand rocks associated with glacial activity. There are various forms of glacial relief. The thickness of the quaternary sediments is extremely uneven, from the first tens of cm to the first tens of m.
Water 17 02418 g001
Figure 1. Geological scheme of investigation area (based on [1,39]), supplemented by locations of sampled mines. Legend: 1—granite rocks of the Salmi batholith; 2—schists of the Ladoga group; 3—amphibolites and amphibole schists with carbonate horizons (Sortavala group); 4—gneissogranites of domes; and 5—sampled mines.
Figure 1. Geological scheme of investigation area (based on [1,39]), supplemented by locations of sampled mines. Legend: 1—granite rocks of the Salmi batholith; 2—schists of the Ladoga group; 3—amphibolites and amphibole schists with carbonate horizons (Sortavala group); 4—gneissogranites of domes; and 5—sampled mines.
Water 17 02418 g001

2.2. Historical Background of the Area and Current State of Research Objects

The Pitkäranta mines are one of the locations of the historic Mining Road [9], from Petrozavodsk on Onega Lake through the territory of Northern Priladozhye to Kuopio in Finland. The area belongs to the boreal-climate region. The first significant publications of information about the geological conditions and ore mining in the Pitkäranta area are the short review by G. Grendal [40] and the monograph by Otto Trüstedt [39]. Otto Trüstedt managed the activities of mining enterprises from 1879 to 1890. Copper mines in this area have been known of since the late 18th century. However, since the mid-19th century, tin and iron have been mined there primarily. The development of deposits was carried out on several ore fields. In the context of geochemical investigations, belonging to the ore field does not play a key role in determining the source and distribution of elements. Therefore, we will focus on the geological location of the mines.
Among the mines, only Herberz-I has the status of being a Karelian heritage site. The remaining mines do not have an approved status, and, as mentioned above, they are not subject to protection and monitoring. Nowadays, abandoned mines become sites of illegal landfills and pose a danger due to the risk of collapse. The situation is especially acute in the “old ore field”, since it is currently a residential area of Pitkäranta. The mines that have survived to this day are flooded (Figure 2). Collapse craters have formed around several shafts. However, most of the existing mines are accessible for investigation.

3. Objects and Methods of Research

3.1. Sampling and Field Measurements

Water samples from flooded mines were collected during field trips in 2018–2023. In total, we collected 54 water samples from the following mines: Herberz-I, Herberz-II, Beck, Lupikko-I, Lupikko-II, Lupikko-III, Lupikko-IV, Schwartz-I, Klara-II, Klara-III, Arsenik, and Limestone (Pelinen Klara) (Figure 1). Some of the abovementioned mines have several shafts connected by galleries. In this case, all shafts were sampled. In other words, all currently accessible mines in the Pitkäranta area were investigated.
We tried to follow a single sampling methodology and analytical procedures. However, there are some differences. For example, samples were taken from the surface to a depth of 3 m in 2018–2022, while in 2023, we were able to conduct investigations to a depth of 80 m. In the early years, we did not have special equipment for surveying and sampling from depth, so the sampling depth was limited to 3 m. In 2023, to determine the physicochemical parameters of natural waters at depth in mine shafts, testing was carried out using a Solinst 3001 logger, which allows for the remote measurement of temperature and electrical conductivity of water at different depths. Then, using a Ruttner bathometer, water samples were taken from shafts at different depths. Several flooded shafts were investigated in this way: Herberz-I, Schwarz-I, Lupikko-I, and Lupikko-III. The depth of the mine shaft survey was limited by hollows that probably occurred at the level of the drifts. The flooded shaft of the Lupikko-I mine was examined to the greatest depth (80 m).
Differences in sampling are taken into account during the data processing and interpretation of the results. Namely, to create a scheme of the heavy metals’ distribution in the waters of historical mines, their contents in the water at the first few meters in depth were taken for the homogeneity of the sample.
In situ measurements included the determination of pH and Eh values, temperature, and dissolved oxygen content using a PH200 m (HM Digital), ORP-200 m (HM Digital), and portable DO meter (WDO-64). Water samples intended for elemental analysis were passed through cellulose acetate or nylon membranes with a 0.45 µm pore size and transferred to 15 mL sterile polypropylene vials. For the analysis of carbonate-system components, chloride, and sulfate ions, the samples were collected in 300 mL plastic bottles that had been thoroughly washed three times with water from the study area. In 2022 and 2023, filtered water was collected in 15 mL vials to determine the ionic composition, additionally.

3.2. Analytical Procedures

The concentrations of Ca, Mg, Na, K, Fe, and Al were determined by ICP-AES (iCAP 6500 DUO, Thermo Scientific, Waltham, MA, USA), while the concentrations of Ni, Cu, Zn, Cd, Pb, As, and other trace elements were analyzed by ICP-MS (X-series 2, Thermo Scientific; X-7 quadrupole mass spectrometer, Thermo Scientific, Waltham, MA, USA). Methodological aspects of analytical determinations of elemental analysis are described in [41]. Components of the carbonate system were determined by potentiometric titration using Expert-001 (Econix-Expert, Moscow, Russia). In addition, the concentrations of Cl− and SO42− were quantified by ionic chromatography (ICS-3000, Thermo Scientific, Sunnyvale, CA, USA), capillary electrophoresis (Kapel 205, Saint Petersburg, Russia), or titration.
Identification of mineral phases was conducted by visual inspection and a Tescan MIRA 3 electron microscope (Brno, Czech Republic) equipped with an X-MAX energy-dispersion spectrometer.

3.3. Data Processing

To assess the degree of concentration of chemical elements in the studied waters, the coefficient Kx proposed by A.I. Perelman [42] was calculated:
Kx = (mx × 100)/(a × nx),
where mx is the content of chemical element x in water (mg/L), a is the sum of mineral substances dissolved in water (mg/L), and nx is the content of element x in the rock (%). The average content of chemical elements in the upper part of the continental crust [43] was taken as the composition of the rocks. According to [42], the group of strong concentration includes elements with a Kx value above 20. The group of medium concentration includes elements with a Kx value from 1 to 20. Values of Kx less than 1 indicate weak or strong dispersion.
To identify patterns in the behavior of chemical elements in water, a correlation matrix was calculated in Jupiter for Python 3.7.4. Since a large number of elements and indicators were processed, a heat map was created using the seaborn library 0.9.0 and then superimposed onto the matrix for better visualization.

4. Results

The mine waters are fresh. Salinity varies from several tens to a few hundred mg/L. The highest salinity values are found in the water of the Lupikko mines. Here the value reaches its maximum among the values 330 mg/L. An increase in salinity with depth was also observed. In addition, some changes in the pH value with depth were noticeable. To be more precise, up to a depth of 10 m an increase in pH is observed, after which a decrease in this indicator occurs. In general, the waters belong to groups that range in pH from slightly acidic (6.33) to slightly alkaline; alkaline (up to 9.1) waters are rare.
Redox conditions changed from oxidizing to reducing at the first few meters in depth. It is noteworthy that, in some mines (Lupikko, Herberz, and Klara-III), reducing conditions are already observed in the surface layers of water. As a rule, redox conditions in mine waters depend on the amount of dissolved oxygen, since this chemical element is the main determinant of oxidation-reduction potential in surface waters. Forestall redox-driven reactions play an important role in the formation of the chemical composition of mine waters, both in our case and in other conditions [44]. The temperature of the water in the mine shafts also changes with depth. Thus, the temperature of the upper layer of water was usually more than +10 °C (sometimes up to +15 °C), while it dropped to +5 °C at a depth of 5 m (in some cases 10 m) and did not change at deeper levels.
Among the chemical types of water, the predominant one is Ca-Mg HCO3. Sulfate ion is elevated in the water of many mines. In some cases, SO42− is dominant. As shown in the Piper diagram (Figure 3), figurative points related to objects of one mine are usually grouped in one zone. The figurative points of the Lupikko mine are located in a line along the HCO3–SO4 axis, which indicates significant variations in the anionic composition. The Lupikko mine is the largest of the historic mines that have survived to this day. This mine consists of several technogenic objects, including, in the case of Lupikko-IV, three shafts, which, from a geochemical point of view, can determine slightly different conditions for the chemical-composition formation. In addition, the depth of the water may also make a difference. As mentioned above, we managed to collect water from the greatest depth in this mine, which accordingly determined the maximum differences in chemical composition associated with this factor. The content of all ions increases with depth, except for the concentration of sulfate ions.
In general, mine waters are characterized by low concentrations of both major ions and trace elements. Thus the normalization of the content of each individual chemical element to the sum of dissolved chemical elements and their content in rocks made it possible to identify the features of the water composition. For this purpose, the concentration coefficient was calculated. The calculations used average data for each mine. In addition, the same profile of chemical elements was calculated for geochemical background data [45] to identify regional patterns (Figure 4).
The chemical elements’ figurative points in regard to location are either closely grouped or, on the contrary, scattered. The figurative points of Ca, Mg, Na, K, Al, Si, Sr, Rb, Ba, Mn, Co, Ti, and Al are located more densely. The group of elements of weak or strong dispersion includes Al, Fe, Si, Ti, V, Co, Ni, Rb, and Ba, while the group of medium concentration consists of Ca, Mg, Na, and Sr. The concentration coefficients of many chemical elements have a wide range of values. This primarily concerns Zn and Cu. Nickel, As, Pb, S, Y, Mo, W, U, and Th can also be included here. Most of the abovementioned chemical elements are siderophilic. The degree of their concentration, as well as the absolute content in the waters of different mines, varies significantly.
In general, the values of the concentration coefficients calculated based on geochemical background values at points such as Ca, Mg, Na, and K are typically higher compared to those calculated for mine waters. Conversely, at points corresponding to trace elements, including heavy metal(loid)s, these values are generally lower or fall within average ranges. This suggests that there is greater accumulation of ore-related elements relative to the concentrations found in natural regional waters.

5. Discussion

Analysis of the distribution of heavy metal(loid)s in the water of flooded mines showed that Zn (Figure 5) is dominant among the range of considered chemical elements (Zn, Cu, As, Cd, Pb, Ni, Co, and Mo). Distribution diagrams are constructed using average data on the contents of heavy metal(loid)s in the surface-layer water and up to 2 m. This set was used to obtain an identical data cut, since not all mines were tested at great depths. Thus, we tried to take into account approximately the same type of water exchange, as well as redox conditions.
Despite the obvious similarity of the association of heavy metal(loid)s in geochemical specification, their distribution in the water of studied mines differs significantly. For example, the average concentration of Zn varies from 1.25 µg/L in Klara-III water to 1764 µg/L in Beck water. Moreover, the maximum concentration of Zn in one of the shafts of Beck is 2660 µg/L, and in Lupikko-IV, it is 5205 µg/L. The source of Zn in the mine waters was sphalerite, which is a common mineral of sulfide mineralization in skarn rocks of the Pitkäranta District [39]. However, during our field trip, visible sphalerite nests (Figure 6a) were found only in the Beck rock dumps.
As a rule, Cu ranks second in content after Zn. The highest Cu content (42 µg/L) was determined in the water of the Schwartz, which is the only surviving mine on the “old ore field”. The average content of Cu in the water of the Lupikko mine was 22 µg/L, with a maximum content of 148 µg/L in the water of Lupikko-IV. Meanwhile, in the other objects, Cu content was up to 5 µg/L.
Arsenic content was generally low. But the mine water of the Arsenik shaft had a high content of As (89 µg/L). Also, high concentrations of As relative to other elements were determined in the water of the Klara-III mine. Löllingite, probably the main source of As in mine waters, was found in the dump rock of the Arsenik shaft (Figure 6c) and Klara-III mines (Figure 6b). The Arsenik shaft and Klara-III mines are located close to each other, and the high As content is probably related to some local geological features. For example, this may be due to the fluid regime of a small sublatitudinal intrusion of leucogranite developed in the northern rim of the Lupikko dome. Nickel, Cd, Pb, Co, and Mo contents are generally quite low. A similar relative distribution of heavy metal(loid)s was observed in the water of the Herberz-I and Herberz-II mines. However, the content of chemical elements in the water of the Herberz-I mine was usually higher than in the Herberz-II mine.
The mines of the northern part of the Lupikko dome also belong to different horizons. Here, the Beck water has an extremely high Zn content. Thus, it can be noted that despite the similar metallogeny of the waters of flooded mines, some differences are noted, and these differences are associated with the different domes they belong to and the metacarbonate horizons framing these domes.
Remarkably, the waters in flooded mines in Sweden, Norway, and Finland contain a similar spectrum of chemical elements to the one our study is concerned with [46,47,48,49]. However, a similar geochemical specification is indeed characteristic of the waters of Finnish mines with near-neutral pH values [50]. The similarity can be explained by similar geological conditions; the location being in a single landscape and climate zone; and the mining activity history, which determines the time of water–rock interaction in flooded mines. The Raajärvi mine, which, like the Pitkäranta mine, is a skarn deposit, has the greatest similarity to our objects of water geochemistry.
The correlation matrix (Figure S1) showed very strong relationships between the content of Ca, Mg, and HCO3− and the salinity. This was a consistent phenomenon, since Ca, Mg, and HCO3− were the dominant ions in the studied waters. There was no noticeable correlation between the SO42− content and salinity. Relatively increased salinity was observed in waters sampled from the depths, while the highest SO42− concentrations were determined in the surface layer of water. As the depth increased, the SO42− content became lower. Probably, at increased depths, when redox conditions changed, S was reduced and, accordingly, the SO42− content decreased. According to studies of the geochemistry of rocks in the Pitkäranta area, the source of most heavy metal(loid)s in the water was sulfide mineralization of rocks [39]. Accordingly, the main process of entry of these elements was the dissolution of sulfide minerals. At the same time, the absence of a strong correlation between S and Fe, Cu, Zn, Pb, As, Mo, and Cd indicates the presence of other processes, such as the precipitation of secondary hypergene minerals, redox reactions, complexation, and sorption (Figure 7).
In addition, numerous factors influenced the formation of the chemical composition of the waters of the flooded mines. Thus, for the accumulation of Ni, Cu, Pb, Zn, Cd, and As, time is a determining factor, which was shown by equilibrium–kinetic modeling of water–rock systems in the Lupikko-I, Beck, and Arsenik Schaft [25,26,51]. In the model, the time and the supply of portions of fresh atmospheric water, as specified parameters, simulated water exchange. However, under natural conditions, water exchange determined the time of interaction of water with rock minerals. Thus, water exchange is a determining factor in the formation of the chemical composition of water, since it essentially combines the time of water–rock interaction and dilution, occurring as a result of atmospheric precipitation entering the mine. In addition, at the depths of the mines, where water exchange is slow, reducing conditions have led to the accumulation of Fe, Mo, and As. At the same time, in the absence of oxygen, dissolution of sulfide minerals does not occur. As a consequence of sulfate reduction, the content of sulfate ions at greater depths is reduced relative to the upper layers, as evidenced by the strong smell of H2S when samples were raised from lower depths. Another factor in the formation of the chemical composition of water was temperature. This was most noticeable in the accumulation of Ca2+ and HCO3−-ions that entered the water when carbonates dissolved. Thus, at a greater depth, the content of these ions is higher, probably due to the greater solubility of carbonates at low temperatures. Here, we are also talking about two interrelated factors—depth and temperature.
One of the main processes of removing chemical elements from water was the formation of secondary mineral phases. A thorough understanding of the mechanisms of secondary mineral formation requires detailed investigation. However, obvious facts were obtained during our field trip and primary study of rock samples. According to visual assessments, secondary minerals of Fe and Cu can be observed on rock fragments in the waste dumps of some mines [26,52]. Probably, in the zone of reducing redox conditions, secondary sulfides are formed.
The process that accumulates chemical elements and, accordingly, blocks the formation of secondary phases was complexation. In fresh water, this process usually does not play a big role [53]. However, this statement does not apply to the formation of species with dissolved organic ligands [54]. This phenomenon is especially evident in the waters of northern regions with a high content of dissolved organic matter [55,56]. Moreover chemical elements that have an affinity for organic matter form stable species within it and thus accumulate in an aqueous solution. This process is observed in the waters of various landscape and climatic zones [55,56,57,58], but, again, it is most intense in the waters of the northern regions [59]. Previously, we conducted studies of heavy metal(loid) speciation using thermodynamic modeling methods [23], as well as experimental fractionation [24], which confirmed this pattern using the example of mine waters of the Pitkäranta District. In general, it can be noted that Pb, Cu, U, Th, Y, V, Ni, Fe, and Cd had a high affinity for organic matter.

6. Conclusions

The research we conducted allowed us to determine the chemical composition of historical mines of the Pitkäranta area and investigate the main geochemical features. The waters are characterized by ore specificity, namely high contents of siderophile elements at low salinity and a circumneutral pH. In the series of elements studied (Zn, Cu, As, Cd, Pb, Ni, Co, and Mo), Zn was found to be in the highest concentrations. The maximum concentration of Zn in one of the shafts of Beck is 2660 µg/L, and in Lupikko-IV, it is 5205 µg/L. The maximum Cu content was determined in the same shaft of Lupikko-IV (148 µg/L). The mine water of the Arsenik shaft had a high content of As (89 µg/L). The oxidative dissolution of sulfide minerals is the main process of heavy metal(loid) transition in natural water. Moreover, the pH is neutralized by the dissolution of carbonate minerals included in the composition of the rocks. In the presence of DOM, heavy metals tend to form stable species, thus promoting their accumulation in water.
The potential toxicity of the considered series of heavy metal(loid)s deserves attention. Obviously, natural waters of the ore area bear the imprint of geochemical specification; however, the mining heritage intensifies the processes of water–rock–organic matter interaction, leading to the accumulation of heavy metal(loid)s in the mine waters. In turn, mine waters can enter the hydrographic network of the area, connecting small lakes and Lake Ladoga. Thus, a set of measures to protect the environment must be implemented. First of all, actions to preserve the mining heritage and organize a safe space around the mines must be carried out. Further assessment of the quality of natural waters in the area is necessary. At sites that are of concern due to the high content of potentially toxic elements, it is necessary to carry out reclamation of the territory. Also, an assessment of the possibility of additional extraction of valuable components from mine waste should be included in a set of measures within the framework of the rational use of natural resources and environmental protection. In addition, increasing the ecological literacy of the Pitkäranta area residents is also a serious challenge.

Supplementary Materials

The following supporting information can be downloaded at https://www.mdpi.com/article/10.3390/w17162418/s1, Figure S1: Correlation matrix for major ions and trace elements of historical mine waters of the Pitkäranta area.

Author Contributions

Sampling, aim of research, visualization of result, and discussion—E.S. and A.K.; introduction and investigation of water chemistry—E.S.; geological essay—A.K. All authors have read and agreed to the published version of the manuscript.

Funding

Sampling and analytical determinations were carried out with the financial support of the Russian Science Foundation (Project No. 22-77-10011). Data analysis and discussion of results were carried out within the framework of the State Task No. FMMG-2022–0001, “Geothermal and hydrochemical anomalies in different tectonic settings”, at the Geological Institute of RAS.

Data Availability Statement

All data are contained within the article and Supplementary Materials.

Acknowledgments

We would like to thank A.S. Toropov and I.A. Bugaev for help with conducting the sampling and I.N. Gromyak, D.N. Dogadkin, A.A. Dolgonosov, and V.N. Kolotygina for the analytical work carried out.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Larin, A.M. Rapakivi Granites and Associated Rocks; Nauka: St. Petersburg, Russia, 2011; p. 402. (In Russian) [Google Scholar]
  2. Mikhailov, V.P.; Aminov, V.N. (Eds.) Mineral and Raw Material Base of the Republic Karelia. Book 1: Combustible Mineral Resources. Metallic Mineral Resources; Kareliya: Petrozavodsk, Russia, 2005; 280p. [Google Scholar]
  3. Mikhailov, V.P.; Aminov, V.N. (Eds.) Mineral and Raw Material Base of the Republic Karelia. Book 2: Non-Metallic Mineral Resources. Underground Waters and Medical Muds; Petrozavodsk: Kareliya, Russia, 2006; 356p. [Google Scholar]
  4. Kookana, R.S.; Drechsel, P.; Jamwal, P.; Vanderzalm, J. Urbanisation and emerging economies: Issues and potential solutions for water and food security. Sci. Total Environ. 2020, 732, 139057. [Google Scholar] [CrossRef]
  5. Gain, A.K.; Giupponi, C.; Wada, Y. Measuring global water security towards sustainable development goals. Environ. Res. Lett. 2016, 11, 124015. [Google Scholar] [CrossRef]
  6. Khatri, N.; Tyagi, S. Influences of natural and anthropogenic factors on surface and groundwater quality in rural and urban areas. Front. Life Sci. 2015, 8, 23–39. [Google Scholar] [CrossRef]
  7. Boyd, C.E. Water quality protection. In Water Quality; Springer: Berlin/Heidelberg, Germany, 2020; pp. 379–409. [Google Scholar] [CrossRef]
  8. Wang, X.; Tao, C.; An, L. Screening Dominant Species and Exploring Heavy Metals Repair Ability of Wild Vegetation for Phytoremediation in Copper Mine. Sustainability 2025, 17, 784. [Google Scholar] [CrossRef]
  9. Shchiptsov, V.V.; Goldenberg, M.L.; Luukkonen, E.; Marin, M. The Road of Mining; Karelian Scientific Center of the Russian Academy of Sciences: Petrozavodsk, Russia, 2014; p. 362. [Google Scholar]
  10. Luo, C.; Routh, J.; Dario, M.; Sarkar, S.; Wei, L.; Luo, D.; Liu, Y. Distribution and mobilization of heavy metals at an acid mine drainage affected region in South China, a post-remediation study. Sci. Total Environ. 2020, 724, 138122. [Google Scholar] [CrossRef]
  11. Acharya, B.S.; Kharel, G. Acid mine drainage from coal mining in the United States—An overview. J. Hydrol. 2020, 588, 125061. [Google Scholar] [CrossRef]
  12. Flores, H.; Lorenz, S.; Jackisch, R.; Tusa, L.; Contreras, I.C.; Zimmermann, R.; Gloaguen, R. UAS-Based Hyperspectral Environmental Monitoring of Acid Mine Drainage Affected Waters. Minerals 2021, 11, 182. [Google Scholar] [CrossRef]
  13. Akcil, A.; Koldas, S. Acid Mine Drainage (AMD): Causes, treatment and case studies. J. Clean. Prod. 2006, 14, 1139–1145. [Google Scholar] [CrossRef]
  14. Simate, G.S.; Ndlovu, S. Acid mine drainage: Challenges and opportunities. J. Environ. Chem. Eng. 2014, 2, 1785–1803. [Google Scholar] [CrossRef]
  15. Grieco, G.; Cocomazzi, G.; Naitza, S.; Bussolesi, M.; Deidda, M.L.; Ferrari, E.S.; Destefanis, E. Recycling Feldspar Mining Waste as Buffering Agent for Acid Mine Drainage Mitigation. Minerals 2024, 14, 552. [Google Scholar] [CrossRef]
  16. Liu, Y.; Xie, X.M.; Wang, S.; Hu, S.M.; Wei, L.Z.; Wu, Q.H.; Luo, D.G.; Xiao, T.F. Hydrogeochemical evolution of groundwater impacted by acid mine drainage (AMD) from polymetallic mining areas (South China). J. Contam. Hydrol. 2023, 259, 104254. [Google Scholar] [CrossRef]
  17. Jarvis, A.P.; Gandy, C.J.; Webb, J.A. Controls on the Generation and Geochemistry of Neutral Mine Drainage: Evidence from Force Crag Mine, Cumbria, UK. Minerals 2023, 13, 592. [Google Scholar] [CrossRef]
  18. Barago, N.; Pavoni, E.; Floreani, F.; Crosera, M.; Adami, G.; Lenaz, D.; Covelli, S. Hydrogeochemistry of thallium and other potentially toxic elements in neutral mine drainage at the decommissioned Pb-Zn Raibl mine (Eastern Alps, Italy). J. Geochem. Explor. 2023, 245, 107129. [Google Scholar] [CrossRef]
  19. Medas, D.; Cidu, R.; De Giudici, G.; Podda, F. Chemical data on environmental matrices from an abandoned mining site. Data Br. 2019, 23, 103801. [Google Scholar] [CrossRef]
  20. Passariello, B.; Giuliano, V.; Quaresima, S.; Barbaro, M.; Caroli, S.; Forte, G.; Carelli, G.; Iavicoli, I. Evaluation of the environmental contamination at an abandoned mining site. Microchem. J. 2002, 73, 245–250. [Google Scholar] [CrossRef]
  21. Navarro, M.C.; Pérez-Sirvent, C.; Martínez-Sánchez, V.J.; Tovar, P.J.; Bech, J. Abandoned mine sites as a source of contami-na-tion by heavy metals: A case study in a semi-arid zone. J. Geochem. Explor. 2008, 96, 183–193. [Google Scholar] [CrossRef]
  22. Wunn, T.D.; Arima, T.; Mufalo, W.; Hamai, T.; Okumura, M.; Mar, K.K.; Tomiyama, S.; Igarashi, T. Impact of effluents from a closed mine on the surrounding water resources: Groundwater contamination of the historical abandoned mine site in Japan. Environ. Monit. Assess. 2025, 197, 1–22. [Google Scholar] [CrossRef]
  23. Konyshev, A.A.; Sidkina, E.S.; Cherkasova, E.V.; Mironenko, M.V.; Gridasov, A.G.; Zhilkina, A.V.; Bugaev, I.A. Migration forms of heavy metals and chemical composition of surface waters in the area of arsenic mine (Pitkaranta ore district, South Karelia). Geochem. Int. 2020, 58, 1068–1074. [Google Scholar] [CrossRef]
  24. Sidkina, E.S.; Toropov, A.S.; Konyshev, A.A. Speciation of Chemical Elements in the Waters of the Herberz Historical Mine, Karelia, Russia: Thermodynamic Calculations and Fractionation. Geochem. Int. 2024, 62, 1200–1218. [Google Scholar] [CrossRef]
  25. Sidkina, E.S.; Soldatova, E.A.; Cherkasova, E.V.; Konyshev, A.A.; Toropov, A.S.; Vorobey, S.S.; Mironenko, M.V. Predicting potential pollutant release from waste rock at the abandoned Beck mine (Karelia, Russia) by equilibrium kinetic modeling. Bull. Geol. Soc. Finl. 2024, 96, 81–96. [Google Scholar] [CrossRef]
  26. Sidkina, E.S.; Soldatova, E.A.; Cherkasova, E.V.; Konyshev, A.A.; Vorobey, S.S.; Mironenko, M.V. Fate of Heavy Metals in the Surface Water-Dump Rock System of the Mine Lupikko I (Karelia): Field Observations and Geochemical Modeling. Water 2022, 14, 3382. [Google Scholar] [CrossRef]
  27. Alekseev, I.A.; Amantov, A.V.; Amantova, M.G.; Babichev, A.V.; Baltybaev, S.K.; Bugaenko, I.V.; Voinov, A.S.; Golubtsova, N.S.; Zhamaletdinov, A.A.; Zaitsev, S.V.; et al. Ladoga Proterozoic Structure (Geology, Deep Structure and Minerageny); Sharov, N.V., Ed.; KarSC RAS: Petrozavodsk, Russia, 2020; p. 435. (In Russian) [Google Scholar]
  28. Velikoslavinsky, D.A. Comparative Characteristics of Regional Metamorphism of Moderate and Low Pressures; Nauka: Leningrad, Russia, 1972; p. 190. (In Russian) [Google Scholar]
  29. Baltybaev, S.K.; Levchenkov, O.A.; Levsky, L.K. The Svecofennian Belt of Fennoscandia: Spatial and Temporal Correlation of Early Proterozoic Endogenous Processes; Nauka: St. Petersburg, Russia, 2009; p. 328. (In Russian) [Google Scholar]
  30. Eskola, P.E. The problem of mantled gneiss domes. Quart. J. Geol. Soc. 1949, 104, 461–476. [Google Scholar] [CrossRef]
  31. Galdobina, L.P.; Melezhik, V.A. Ludikovian stratigraphy of the eastern part of the Baltic Shield. In Proceedings of the Finnish-Soviet Symposium Early Proterozoic of the Baltic Shield, Petrozavodsk, Russia, 19–27 August 1986. (In Russian). [Google Scholar]
  32. Svetov, A.P.; Sviridenko, L.P. Precambrian Stratigraphy of Karelia. Sortavala Series of Svekokarelides of Ladoga Region; Russian Academy of Sciences Karelian Scientific Center, Institute of Geology: Petrozavodsk, Russia, 1992; p. 152. (In Russian) [Google Scholar]
  33. Vrevsky, A.B.; Matrenichev, V.A.; Sergeev, S.A.; Larionov, A.N.; Bogomolov, E.S. Geochronological and isotope-geochemical substantiation of the ensialic nature of the supracrustal formations of the Sortavala series in the junction zone of the Karelian and Svekofennian geoblocks of the Fennoscandian shield. In Proceedings of the III Conference on Isotope Geochronology, Moscow, Russia, 2–6 June 2006. (In Russian). [Google Scholar]
  34. Gorokhov, I.M.; Kuznetsov, A.B.; Azimov, P.Y.; Dubinina, E.O.; Vasilieva, I.M.; Rizvanova, N.G. Sr and C Isotope Chemostratigraphy of the Paleoproterozoic Metacarbonate Rocks of the Sortavala Group: Fennoscandian Shield, Northern Ladoga Area. Stratigr. Geol. Correl 2021, 29, 121–139. [Google Scholar] [CrossRef]
  35. Neymark, L.A.; Amelin, Y.V.; Larin, A.M. Pb-Nd-Sr isotopic and geochemical constraints on the origin of the 1.54–1.56 Ga Salmi rapakivi granite—Anorthosite batholith (Karelia, Russia). Contrib. Mineral. Petrol. 1994, 50, 173–193. [Google Scholar] [CrossRef]
  36. Amelin, Y.V.; Larin, A.M.; Tucker, R.D. Chronology of multiphase emplacement of the Salmi rapakivi granite-anorthosite complex, Baltic Shield: Implications for magmatic evolution. Contrib. Mineral. Petrol. 1997, 127, 353–368. [Google Scholar] [CrossRef]
  37. Dukhovskiy, A.A.; Artamonova, N.A.; Ivanova, E.I.; Nikiforov, I.O. A volumetric model of the Salmi rapakivi granite massif and the regularities of mineralization placement. Otechestvennaya Geol. 1994, 4, 24–32. (In Russian) [Google Scholar]
  38. Rämö, O.T.; Mänttäri, I.; Vaasjoki, M.; Upton, B.G.J.; Sviridenko, L. Age and significance of Mesoproterozoic CFB magmatism, Lake Ladoga region, NW Russia. In Proceedings of the A Geo-Odyssey, Boston, MA, USA, 1–10 November 2001. [Google Scholar]
  39. Trüstedt, O. Die Erzlagerstätten von Pitkäranta am Ladoga-See. Bull. La Comm. Géol. Finl. 1907, 19, 258–276. (In German) [Google Scholar]
  40. Grendal, G. Pitkäranta (Brief Description of Pitkäranta Deposit, Mines, Factories). Typo-Lithography by A.E.; Wieneke: St. Petersburg, Russia, 1896; p. 50. [Google Scholar]
  41. Bol’shov, M.A.; Karandashev, V.K.; Tsisin, G.I.; Zolotov, Y.A. Flow methods for the determination of elements in solutions based on sorption preconcentration and inductively coupled plasma mass spectrometry. J. Anal. Chem. 2011, 66, 548–564. [Google Scholar] [CrossRef]
  42. Perelman, A.I. Geochemistry of Natural Waters; Nauka: Moscow, Russia, 1982; p. 154. (In Russian) [Google Scholar]
  43. Grigoriev, N.A. Chemical Element Distribution in the Upper Continental Crust; UB RAS: Ekaterinburg, Russia, 2009; p. 383. (In Russian) [Google Scholar]
  44. Johnston, S.G.; Bennett, W.W.; Doriean, N.; Hockmann, K.; Karimian, N.; Burton, E.D. Antimony and arsenic speciation, redox-cycling and contrasting mobility in a mining-impacted river system. Sci. Total Environ. 2020, 710, 136354. [Google Scholar] [CrossRef]
  45. Ministry of Natural Resources and Ecology of the Russian Federation. State Report on the Conditions and Use of Mineral Resources of the Russian Federation in 2021; Ministry of Natural Resources and Ecology of the Russian Federation, Subsurface Resources Management (Rosnedra): Moscow, Russia, 2022; p. 621. Available online: https://vims-geo.ru/ru/documents/714/%D0%9A%D0%BD%D0%B8%D0%B3%D0%B0_%D0%93%D0%94-2021_web_2023.01.18_8.pdf (accessed on 9 June 2025).
  46. Banks, D.; Younger, P.L.; Arnesen, R.; Iversen, E.R.; Banks, S.B. Mine-water chemistry: The good, the bad and the ugly. Environ. Geol. 1997, 32, 157–174. [Google Scholar] [CrossRef]
  47. Parviainen, A. Tailings mineralogy and geochemistry at the abandoned Haveri Au–Cu mine, SW Finland. Mine Water Environ. 2009, 28, 291–304. [Google Scholar] [CrossRef]
  48. Heikkinen, P.M.; Korkka-Niemi, K.; Lahti, M.; Salonen, V.P. Groundwater and surface water contamination in the area of the Hitura nickel mine, Western Finland. Environ. Geol. 2002, 42, 313–329. [Google Scholar] [CrossRef]
  49. Holmström, H.; Ljungberg, J.; Öhlander, B. The character of the suspended and dissolved phases in the water cover of the flooded mine tailings at Stekenjokk, northern Sweden. Sci. Total Environ. 2000, 247, 15–31. [Google Scholar] [CrossRef]
  50. Kauppila, P.M.; Räisänen, M.L. Effluent chemistry of closed sulfide mine tailings—Influence of ore type. In Proceedings, 10th ICARD and IMWA Conference, Santiago, Chile, 21–24 April 2015; Brown, A., Bucknam, C., Burgess, J., Carballo, M., Castendyk, D., Figueroa, L., Kirk, L., McLemore, V., McPhee, J., O’Kane, M., et al., Eds.; IMWA: Wendelstein, Germany, 2015; pp. 264–273. [Google Scholar]
  51. Cherkasova, E.V.; Konyshev, A.A.; Soldatova, E.A.; Sidkina, E.S.; Mironenko, M.V. Metal Speciation in Water of the Flooded Mine “Arsenic” (Karelia, Russia): Equilibrium-Kinetic Modeling with a Focus on the Influence of Humic Substances. Aquat. Geochem. 2021, 27, 141–158. [Google Scholar] [CrossRef]
  52. Konyshev, A.A.; Sidkina, E.S.; Bugaev, I.A. A Study on the Long-Term Exposure of a Tailings Dump, a Product of Processing Sn-Fe-Cu Skarn Ores: Mineralogical Transformations and Impact on Natural Water. Sustainability 2024, 16, 1795. [Google Scholar] [CrossRef]
  53. Krainov, S.R.; Ryzhenko, B.N.; Shvets, V.M. Groundwater Geochemistry. Theoretical, Applied, and Ecological Aspects; TsentrLitNefteGaz: Moscow, Russia, 2012; p. 672. [Google Scholar]
  54. Lepokurova, O.E.; Ivanova, I.S.; Trifonov, N.S.; Kolubaeva, Y.V.; Sokolov, D.A. Dissolved forms of migration of humic substances in surface water bodies of the Yamal-Nenets autonomous district. Bull. Tomsk. Polytech. Univ. Geo Assets Eng. 2022, 333, 56–69. [Google Scholar] [CrossRef]
  55. Ivanova, I.; Savichev, O.; Trifonov, N.; Kolubaeva, Y.V.; Volkova, N. Major-Ion Chemistry and Quality of Water in Rivers of Northern West Siberia. Water 2021, 13, 3107. [Google Scholar] [CrossRef]
  56. Kaiser, K.; Canedo-Oropeza, M.; McMahon, R.; Amon, R.N. Origins and transformations of dissolved organic matter in large Arctic rivers. Sci. Rep. 2017, 7, 13064. [Google Scholar] [CrossRef] [PubMed]
  57. Vega, F.A.; Weng, L. Speciation of heavy metals in River Rhine. Water Res. 2013, 47, 363–372. [Google Scholar] [CrossRef] [PubMed]
  58. Tang, W.; Sun, L.; Zhu, Y.; Ng, J.C.; Huang, J.; Xu, Z.; Zhang, H. Difference analysis of organic matter-mediated heavy metal pollution in the sediments of urban water bodies. Sci. Total Environ. 2025, 968, 178747. [Google Scholar] [CrossRef]
  59. Miller, C.B.; Parsons, M.B.; Jamieson, H.E.; Ardakani, O.H.; Patterson, R.T.; Galloway, J.M. Mediation of arsenic mobility by organic matter in mining-impacted sediment from sub-Arctic lakes: Implications for environmental monitoring in a warming climate. Environ. Earth. Sci. 2022, 81, 137. [Google Scholar] [CrossRef]
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Figure 2. Current status of some mines of the Pitkäranta area: (a) Herberz-I; (b) Klee-IV (the shaft top is covered by a concrete block, is located in the town of Pitkäranta, and is not accessible); (c) Valkealampi (a subsidence crater; the shaft top is filled in by ground and is not accessible); and (d) Schwartz-I (the shaft top is mostly closed, the round camera cover on photo is 49 cm in diameter, and the mine is located in the town of Pitkäranta).
Figure 2. Current status of some mines of the Pitkäranta area: (a) Herberz-I; (b) Klee-IV (the shaft top is covered by a concrete block, is located in the town of Pitkäranta, and is not accessible); (c) Valkealampi (a subsidence crater; the shaft top is filled in by ground and is not accessible); and (d) Schwartz-I (the shaft top is mostly closed, the round camera cover on photo is 49 cm in diameter, and the mine is located in the town of Pitkäranta).
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Figure 3. Piper diagram for the natural waters of the historical mines of the Pitkäranta area.
Figure 3. Piper diagram for the natural waters of the historical mines of the Pitkäranta area.
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Figure 4. Accumulation coefficients for some elements in the waters of the historical mines of the Pitkäranta area. Elements with the greatest spread of values are indicated by red ellipses.
Figure 4. Accumulation coefficients for some elements in the waters of the historical mines of the Pitkäranta area. Elements with the greatest spread of values are indicated by red ellipses.
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Figure 5. Distribution of heavy metal(loid)s in the waters of historical mines of the Pitkäranta area (µg/L).
Figure 5. Distribution of heavy metal(loid)s in the waters of historical mines of the Pitkäranta area (µg/L).
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Figure 6. Samples collected from the Beck (a), Klara-III (b), and Arsenik shaft (c) dump. Mineral indices: Sp—sphalerite; Lö—löllingite; Ccp—chalcopyrite; Flr—chalcopyrite; and Qz—quartz. The size scale is in centimeters.
Figure 6. Samples collected from the Beck (a), Klara-III (b), and Arsenik shaft (c) dump. Mineral indices: Sp—sphalerite; Lö—löllingite; Ccp—chalcopyrite; Flr—chalcopyrite; and Qz—quartz. The size scale is in centimeters.
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Figure 7. Schematic representation of the processes of formation of the chemical composition of water in a mine shaft.
Figure 7. Schematic representation of the processes of formation of the chemical composition of water in a mine shaft.
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Sidkina, E.; Konyshev, A. Flooded Historical Mines of the Pitkäranta Area (Karelia, Russia): Heavy Metal(loid)s in Water. Water 2025, 17, 2418. https://doi.org/10.3390/w17162418

AMA Style

Sidkina E, Konyshev A. Flooded Historical Mines of the Pitkäranta Area (Karelia, Russia): Heavy Metal(loid)s in Water. Water. 2025; 17(16):2418. https://doi.org/10.3390/w17162418

Chicago/Turabian Style

Sidkina, Evgeniya, and Artem Konyshev. 2025. "Flooded Historical Mines of the Pitkäranta Area (Karelia, Russia): Heavy Metal(loid)s in Water" Water 17, no. 16: 2418. https://doi.org/10.3390/w17162418

APA Style

Sidkina, E., & Konyshev, A. (2025). Flooded Historical Mines of the Pitkäranta Area (Karelia, Russia): Heavy Metal(loid)s in Water. Water, 17(16), 2418. https://doi.org/10.3390/w17162418

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