Article
Soil contaminated with hazardous waste materials at Rio Tinto mine (Spain) is a persistent secondary source of acid and heavy metals to the environment
Author/s | Fernández Landero, Sandra
Fernández Caliani, Juan Carlos Giráldez, María Inmaculada Morales, Emilio Barba Brioso, Cinta González Díez, María Isabel |
Department | Universidad de Sevilla. Departamento de Cristalografía, Mineralogía y Química Agrícola |
Publication Date | 2023-03-23 |
Deposit Date | 2024-03-15 |
Published in |
|
Abstract | Mineralogical analysis and laboratory-based leaching tests coupled with speciation modeling were undertaken to quantify the potential for short-term acid generation and the release of
trace elements from soils heavily ... Mineralogical analysis and laboratory-based leaching tests coupled with speciation modeling were undertaken to quantify the potential for short-term acid generation and the release of trace elements from soils heavily contaminated with mine waste at Rio Tinto. Three different waste materials were considered as case studies: roasted pyrite, copper slags, and leached sulfide ores. The results showed elevated values of net acid generation (up to 663 mmol H+/kg), the major pools being potential sulfidic acidity and acidity retained in jarosite. Remarkable contents of As and toxic heavy metals were found especially in the slag-contaminated soil. Copper, Zn, and Pb were the most abundant metals in the acid leach solutions resulting from mine soil-water interaction, with peak values of 55.6 mg L−1 , 2.77 mg L−1 , and 2.62 mg L−1 , respectively. Despite the high total contents of trace elements occurring in soil, the mobile fraction was limited to maximum release values of 12.60% for Cd and 10.27% for Cu, according to the test leaching. Speciation calculations indicated that free metal ions (M2+) and sulfate species (MSO4 0 ) accounted for most of the dissolved load. Acid soil drainage is a secondary source of acid and heavy metals in the mine site and, therefore, an effective land reclamation program should ensure that acidity and metal mobility are reduced to environmentally sustainable levels. |
Funding agencies | Junta de Andalucía European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER) |
Project ID. | 2014-2020 P-18-TP-3503 |
Citation | Fernández Landero, S., Fernández Caliani, J.C., Giráldez, M.I., Morales, E., Barba Brioso, C. y González Díez, M.I. (2023). Soil contaminated with hazardous waste materials at Rio Tinto mine (Spain) is a persistent secondary source of acid and heavy metals to the environment. Minerals, 13 (4), 456. https://doi.org/10.3390/min13040456. |
Files | Size | Format | View | Description |
---|---|---|---|---|
minerals-13-00456-v3.pdf | 8.975Mb | [PDF] | View/ | |