Academic Journal
Geochemical assessment of soil and water around abandoned gold mine tailings dams: evidence from the Welkom Goldfield, South Africa.
| Τίτλος: | Geochemical assessment of soil and water around abandoned gold mine tailings dams: evidence from the Welkom Goldfield, South Africa. |
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| Συγγραφείς: | Makhadi R; Department of Geology, University of the Free State, Bloemfontein, South Africa.; Department of Geology, University of Johannesburg, Johannesburg, South Africa., Hansen R; Department of Geology, University of the Free State, Bloemfontein, South Africa., Dowling K; STEM College, RMIT University, Melbourne, Australia., Mouri H; Department of Geology, University of Johannesburg, Johannesburg, South Africa. hmouri@uj.ac.za. |
| Πηγή: | Environmental geochemistry and health [Environ Geochem Health] 2026 Oct 04; Vol. 48 (15). Date of Electronic Publication: 2026 Oct 04. |
| Τύπος έκδοσης: | Journal Article |
| Γλώσσα: | English |
| Στοιχεία περιοδικού: | Publisher: Kluwer Academic Publishers Country of Publication: Netherlands NLM ID: 8903118 Publication Model: Electronic Cited Medium: Internet ISSN: 1573-2983 (Electronic) Linking ISSN: 02694042 NLM ISO Abbreviation: Environ Geochem Health Subsets: MEDLINE |
| Imprint Name(s): | Publication: 1999- : Dordrecht : Kluwer Academic Publishers Original Publication: Kew, Surrey : Science and Technology Letters, 1985- |
| Ιατρικοί όροι (MeSH): | Soil Pollutants*/analysis , Water Pollutants, Chemical*/analysis , Soil*/chemistry , Mining* , Gold*, Drinking Water/analysis ; South Africa ; Environmental Monitoring ; Water Quality |
| Περίληψη: | Gold mining in Welkom, South Africa, has generated abandoned mine tailings containing potentially toxic elements, some located near residential and agricultural areas. This study evaluated soil and water geochemistry around abandoned tailings, emphasising ecological and human-health risks. Soil and water samples were collected near and away from abandoned mine tailings and analysed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Soil samples were assessed for total and leachable element concentrations. Water contamination was quantified by computing a drinking water quality index (WQI). Mean soil concentrations (mg/kg) were highest for Fe (18,425), Mn (273) and Cr (200), often highest near tailings. Uranium, detected for the first time in the area, reached 49 mg/kg. Manganese had the highest leachable concentration (15 mg/kg), while As ranged from 3 to 304 mg/kg and exceeded the Dutch (2000) and South Africa's Department of Environmental Affairs (2008) regulatory limits of 29 and 5.8 mg/kg, respectively. Contamination indices indicated low to high contamination of As, Co, Cr, Ni, Pb and U. Considerable potential ecological risks (E (© 2026. The Author(s).) |
| Competing Interests: | Declarations. Conflict of interest: The authors declare no competing interests. |
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| Contributed Indexing: | Keywords: Abandoned mine tailings; Acid mine drainage; Contamination factor; Ecological risk; Geoaccumulation index; Water quality index |
| Substance Nomenclature: | 7440-57-5 (Gold) 0 (Soil Pollutants) 0 (Water Pollutants, Chemical) 0 (Soil) 0 (Drinking Water) |
| Entry Date(s): | Date Created: 20261003 Date Completed: 20261003 Latest Revision: 20261012 |
| Update Code: | 20261012 |
| PubMed Central ID: | PMC13633954 |
| DOI: | 10.1007/s10653-026-03513-0 |
| PMID: | 42829349 |
| Βάση Δεδομένων: | MEDLINE |
| ISSN: | 1573-2983 |
|---|---|
| DOI: | 10.1007/s10653-026-03513-0 |