title: Spread and partitioning of arsenic in soils from a mine waste site in Madrid province (Spain).
abstract: The formation of scorodite is an important mechanism for the natural attenuation of arsenic in a wide range of environments. It is dumped on site by metallurgical industries to minimize arsenic release. However, the long-term stability of these deposits is unclear. Sequential As extractions and synchrotron-based X-ray absorption near-edge structure (XANES) spectroscopy were used to determine both As and Fe speciation in a small catchment area affected by a scorodite-rich waste pile at an abandoned smelting factory. Our results indicate that this deposit behaves as an acute point source of As and metal pollution and confirms the strong association of As(V) with Fe(III) oxide phases, highlighting the important role of ferrihydrite as an As scavenger in natural systems. In this seasonally variable system, other trapping forms such as jarosite-like minerals also play a role in the attenuation of As. Overall, our results demonstrate that scorodite should not be considered an environmental stable repository for As attenuation when dumped outside because natural rainfall and the resulting runoff drive As dispersion in the environment and indicate the need to monitor and reclamate As-rich mine deposits.
authors.affiliation: National Museum of Natural Sciences, CSIC, Jose Gutierrez Abascal 2, 28006 Madrid, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Gomez-Gonzalez
authors.affiliation: Institute of Agrochemistry and Food Technology, CSIC, Catedratico Agustin Escardino 9, 46980 Paterna, Valencia, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Serrano
authors.affiliation: Group of Analytical Spectroscopy and Sensors, Institute of Environmental Sciences, University of Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Laborda
authors.affiliation: National Museum of Natural Sciences, CSIC, Jose Gutierrez Abascal 2, 28006 Madrid, Spain. Electronic address: fernando.garrido@mncn.csic.es.
authors.forename: F
authors.initials: F
authors.lastname: Garrido
mesh_terms: D001151:Arsenic / Q000032:analysis*; D004784:Environmental Monitoring; D008906:Mining; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D013030:Spain
chemical_list: D012987:Soil; D012989:Soil Pollutants; D001151:Arsenic
keywords: Arsenic; Metal soil pollution; Point source pollution; Scorodite; XANES