Spatial variability of soils and stream sediments and the remediation effects in a Portuguese uranium mine area |
| |
| Institution: | 1. Geobiotec, Department of Geosciences, University of Aveiro, Portugal;2. Department of Earth Sciences, University of Coimbra, Portugal;3. Instituto Politécnico de Castelo Branco and CERENA/FEUP-Centro de Recursos Naturais e Ambiente, Portugal;4. CNC-Centre for Neuroscience and Cell Biology, University of Coimbra, Portugal;5. MARE-Marine and Environmental Science Centre, University of Coimbra, Portugal;6. Starplan, Natural History Museum of Denmark, University of Copenhagen, Denmark;1. Department of Geology, Tarbiat Modares University, Tehran 14115–175, Iran;2. Mining Department, Faculty of Engineering, University of Kurdistan, 66177–15175, Sanandaj, Iran;3. Graduate School of Environmental Studies, Department of Earth and Environmental Sciences, Nagoya University, Nagoya, Japan;4. School of Earth & Ocean Sciences, Cardiff University, Cardiff, United Kingdom;5. Geobiotec, Departamento de Geociências, Universidade de Aveiro, 3810–193 Aveiro, Portugal, Portugal;1. Ruhr-Universität Bochum, Institut für Geologie, Mineralogie und Geophysik, Universitätsstr. 150, 44780 Bochum, Germany;2. Instituto de Ciências da Terra, Departamento de Geociências, Ambiente e Ordenamento do Território, Rua do Campo Alegre 687, 4169-007 Porto, Portugal;3. Institut Pluridisciplinaire Hubert Curien, UMR 7178, 23 Rue Becquerel, 67087 Strasbourg, France;1. Institute for Geological and Geochemical Research, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, H-1112 Budapest, Budaörsi út 45., Hungary;2. Department of Earth Sciences, University of Bristol, Wills Memorial Building, Queen’s Road, Bristol BS8 1RJ, United Kingdom;3. Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Magyar tudósok körútja 2., Hungary;1. Geology Department, The University of Jordan, Amman 11942, Jordan;2. Leibniz University Hannover, Germany |
| |
| Abstract: | The old Senhora das Fontes uranium mine, located in central Portugal, was closed down in 1971. The treatment of ores from this mine and other mines by heap-leach ended in 1982. Seven dumps partially covered by vegetation were left in the area. Soil and stream sediment samples were collected in December 2009. The remediation was carried out from May 2010 to January 2011. Stream sediment samples were collected again in October 2013. Before the remediation, soils from inside the mine influence area have higher Al, As, Co, Cr, Cu, Fe, Ni, Sr, Th, U and Zn concentrations than soils from outside this area, due to radionuclides, metals and metalloid released from the mine dumps. The principal component analysis (PCA) shows a distinction between soils from inside and outside the mine influence area. The U(VI), As(V) and metals from soils can be adsorbed to Fe-oxyhydroxides and the humic acid can increase the U uptake. Soils must not be used for public or private green and residential areas, because they are contaminated in U, As, Co, Cd and Ni. Before the remediation, downstream sediments have higher Al, As, Cu, Mn, Ni, Pb, U and Zn than upstream sediments, due to erosion and percolation of water through the mine dumps. The PCA shows a distinction between downstream and upstream sediments. The U(VI), Th and As(V) can be adsorbed to Fe-oxyhydroxides. The stream sediments are contaminated in As, Mn, Th and U. Downstream sediments are the most contaminated in U and As. After the remediation, upstream and downstream sediments have generally higher Al, Fe, As, Cr, Ni, Th, U and Zn concentrations than before the remediation, attributed to the relocation of dumps. Radionuclides, metals and metalloids were transported by surface water. Consequently downstream sediments have higher Al, As, Cu, Mn, Ni, Th, U and Zn concentrations than upstream sediments. The U(VI), Th and As(V) can be adsorbed to Fe-oxyhydroxides. Stream sediments became more contaminated in U, Th and As than before the remediation, but more intensively downstream. |
| |
| Keywords: | Uranium Thorium Arsenic Uranium mine Spatial distribution Soils Stream sediments Before remediation After remediation Contamination |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
