Trace Elements in Sediments of Rivers Affected by Brown Coal Mining: A Potential Environmental Hazard
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Site
2.2. Sample Collection
2.3. Chemical Analysis
2.4. Data Analysis
2.5. Heavy Metal Pollution and Potential Ecotoxicological Risk Assessment
2.6. Rare Earth Element Concentration and Variability
2.7. Statistical Analysis
3. Results
4. Discussion
5. Conclusions
- Mine water discharge can modify concentrations of heavy metals and rare earth elements in sediments, causing a decrease in concentration at sites located close to the mine and an increase concentrations at sites located downstream of the full mixing zone;
- The main factor reducing the concentrations of heavy metals and rare earth elements in sediments is the kinetic energy of the water, which causes the washing away of the fine particles and organic matter;
- Mine water discharges do not change the pattern of individual rare earth elements in sediments;
- Studied sites located downstream of discharge showed a lack of ecological risk according to the presence of metals, except Widawka River, where risk was also observed upstream of mine water discharge;
- Mine waters from surface drainage should be kept longer in settling ponds to reduce total suspended solids with HMs and REEs bonded to them. This requires the creation of settling ponds with increased volume to increase retention time of mine waters;
- The length of full mixing should be limited to enhance river self-purification after the inflow of mine waters to the watercourse.
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Conflicts of Interest
References
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Index | B1 | B2 | B3 | D1 | D2 | D3 | L1 | L2 | L3 | T1 | T2 | T3 |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Pollution assessment | ||||||||||||
CFCr | 2.64 | 0.76 | 1.87 | 0.57 | 0.02 | 0.42 | 0.11 | 0.02 | 0.11 | 0.31 | 0.19 | 0.15 |
CFNi | 14.09 | 4.88 | 9.93 | 0.60 | 0.08 | 0.38 | 0.14 | 0.11 | 0.19 | 0.38 | 0.25 | 0.21 |
CFCu | 2.47 | 1.48 | 1.34 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 |
CFZn | 5.48 | 2.15 | 4.20 | 0.96 | 1.44 | 0.93 | 0.89 | 0.65 | 0.97 | 0.94 | 1.42 | 1.46 |
CFCd | 1.30 | 0.23 | 0.99 | 0.08 | 0.05 | 0.10 | 0.03 | 0.03 | 0.05 | 0.05 | 0.08 | 0.03 |
CFPb | 1.82 | 1.87 | 1.38 | 0.22 | 0.05 | 0.20 | 0.08 | 0.05 | 0.09 | 0.16 | 0.15 | 0.07 |
PLI | 3.25 | 1.32 | 2.29 | 0.21 | 0.07 | 0.19 | 0.09 | 0.06 | 0.11 | 0.16 | 0.16 | 0.11 |
PI | 10.49 | 3.70 | 7.39 | 0.74 | 1.04 | 0.70 | 0.65 | 0.47 | 0.71 | 0.70 | 1.04 | 1.06 |
Ecological risk assessment | ||||||||||||
ERCr | 5.3 | 1.5 | 3.7 | 1.1 | 0.0 | 0.8 | 0.2 | 0.0 | 0.2 | 0.6 | 0.4 | 0.3 |
ERNi | 70.4 | 24.4 | 49.6 | 3.0 | 0.4 | 1.9 | 0.7 | 0.6 | 0.9 | 1.9 | 1.3 | 1.1 |
ERCu | 12.4 | 7.4 | 6.7 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 |
ERZn | 5.5 | 2.2 | 4.2 | 1.0 | 1.4 | 0.9 | 0.9 | 0.7 | 1.0 | 0.9 | 1.4 | 1.5 |
ERCd | 39.0 | 7.0 | 29.6 | 2.3 | 1.6 | 3.1 | 0.8 | 0.8 | 1.6 | 1.6 | 2.3 | 0.8 |
ERPb | 9.1 | 9.4 | 6.9 | 1.1 | 0.2 | 1.0 | 0.4 | 0.2 | 0.5 | 0.8 | 0.8 | 0.3 |
PERI | 141.6 | 51.8 | 100.8 | 8.6 | 3.7 | 7.8 | 3.1 | 2.4 | 4.3 | 5.9 | 6.2 | 4.0 |
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Staniszewski, R.; Niedzielski, P.; Sobczyński, T.; Sojka, M. Trace Elements in Sediments of Rivers Affected by Brown Coal Mining: A Potential Environmental Hazard. Energies 2022, 15, 2828. https://doi.org/10.3390/en15082828
Staniszewski R, Niedzielski P, Sobczyński T, Sojka M. Trace Elements in Sediments of Rivers Affected by Brown Coal Mining: A Potential Environmental Hazard. Energies. 2022; 15(8):2828. https://doi.org/10.3390/en15082828
Chicago/Turabian StyleStaniszewski, Ryszard, Przemysław Niedzielski, Tadeusz Sobczyński, and Mariusz Sojka. 2022. "Trace Elements in Sediments of Rivers Affected by Brown Coal Mining: A Potential Environmental Hazard" Energies 15, no. 8: 2828. https://doi.org/10.3390/en15082828