title: Long-term contamination in a recovered area affected by a mining spill.
abstract: Soil pollution from the spill of Aznalcóllar mine (S Spain) was monitored by analysing polluted soils in 1998, 1999, and 2004. Following the methodology used in previous studies, in 2013 we conducted a new sampling and analysis of the soils affected by the spill and the data were compared with those of 2004. The results confirm that the pH tended to rise and concentration of pollutants tended to diminish over time. In 2013, the total concentration of pollutants was within the normal range for uncontaminated soils and close to the background concentration of the soils prior to the spill; while the soluble concentration of pollutants was clearly below the toxic level. These results indicate that remediation measures implemented have been effective. However, the removal of tailings (first remediation measure applied) was deficient and in many places the tailings were mixed with the soil. The high concentration of sulphides and metal(loid)s in the tailings gave rise to spots with very acidic and highly polluted soils devoid of vegetation. In 2013, fifteen years after the spill, these spots of bare soils remain a major source of pollution from which pollutants are scattered through the solid and liquid phases of runoff water, requiring action to immobilize pollutants and encourage the restoration of vegetation on these soils. In this type of pollution in a Mediterranean environment, the complete removal of tailings is more important than the speed at which they are removed.
authors: Departamento de Edafología y Química Agrícola, Facultad de Ciencias, Universidad de Granada, Campus Fuentenueva s/n, 18002 Granada, Spain. Electronic address: fjmartin@ugr.es.
authors: F J
authors: FJ
authors: Martín Peinado
authors: Departamento de Edafología y Química Agrícola, Facultad de Ciencias, Universidad de Granada, Campus Fuentenueva s/n, 18002 Granada, Spain.
authors: A
authors: A
authors: Romero-Freire
authors: Departamento de Edafología y Química Agrícola, EPS CITE IIB, Universidad de Almería, Campus de Excelencia Internacional Agroalimentario ceiA3, Carretera Sacramento s/n, 04120 Almería, Spain.
authors: I
authors: I
authors: García Fernández
authors: Departamento de Edafología y Química Agrícola, Facultad de Ciencias, Universidad de Granada, Campus Fuentenueva s/n, 18002 Granada, Spain.
authors: M
authors: M
authors: Sierra Aragón
authors: Departamento de Edafología y Química Agrícola, Facultad de Ciencias, Universidad de Granada, Campus Fuentenueva s/n, 18002 Granada, Spain.
authors: I
authors: I
authors: Ortiz-Bernad
authors: Departamento de Edafología y Química Agrícola, EPS CITE IIB, Universidad de Almería, Campus de Excelencia Internacional Agroalimentario ceiA3, Carretera Sacramento s/n, 04120 Almería, Spain.
authors: M
authors: M
authors: Simón Torres
mesh_terms: D004784:Environmental Monitoring; D004787:Environmental Pollution / Q000706:statistics & numerical data; D019216:Metals, Heavy / Q000032:analysis; D008906:Mining; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*; D013030:Spain
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants
keywords: Arsenic; Aznalcóllar spill; Heavy metals; Soil remediation