Atlas Biogeoquímico de Castilla-La Mancha. Primeros resultados comparativos en los sinclinales de Guadalmez y Almadén (Ciudad Real)

Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu

Categorization of Mining Materials for Restoration Projects by Means of Pollution Indices and Bioassays

Sulfide mining wastes may lead to severe environmental and human health risks. This study aims to use geochemical and ecotoxicological indicators for the assessment of the ecological risks of potentially toxic elements (PTEs) in the San Quintín mining group to categorize wastes prior to mining restoration. Ecotoxicity was evaluated using crustacean (Dahpnia magna, Thamnocephalus platyurus) and algae (Raphidocelis subcapitata) bioassays. The geochemical and mineralogical results suggested that the mining residues underwent intense weathering processes, with active processes of acidity generation and metal mobility. Total PTEs concentrations indicated that the mining materials were extremely polluted, with Pb, Zn and Cd geoaccumulation index (Igeo) values higher than 5 in more than 90% of the samples. The pollution load index (PLI) showed average values of 18.1, which classifies them as very highly polluted. The toxicity tests showed a higher toxicity for plants than crustaceans, being the highest values of toxicity related to toxic elements (Pb, Cd and Zn), electrical conductivity and to pH. This paper presents for the first time the combination of indices in the categorization of mining waste prior to its restoration. The combination of them has made it possible to categorize the waste and adapt the restoration and remediation procedures.Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEMinisterio de Ciencia e Innovaciónpu

Caracterización biogeoquímica de la afectación al suelo del área de la mina del Quinto del Hierro, Almadenejos, Ciudad Real

Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu

Modeling of atmospheric mercury emissions from a mining area

En la presente comunicación se analizan datos de dispersión de mercurio en el entorno de una instalación minera, actualmente utilizada para el almacenamiento de este metal en estado líquido en las proximidades de Almadén. Para ello se han comparado dos modelos de dispersión, uno basado en datos reales de inmisión de vapor de mercurio en la zona, y el segundo basado en la distribución teórica gaussiana que se genera a partir de un foco único de emisión, que sería la instalación mencionada. Los resultados obtenidos indican que la emisión generada a partir de la instalación es de muy escasa importancia, ya que produciría un incremento de la inmisión del vapor de mercurio en su entorno del orden de 1 a 3 ng Hg · m-3. De hecho, en el modelo obtenido a partir de los datos reales no se aprecia la influencia de la emisión generada por esta instalación, sino que podría ser interpretado en base a la presencia de antiguas escombreras y zonas de actividad minera en general.The present work deals with the analysis of mercury vapour dispersion around an old mine area, presently used as a storage facility. To perform such analysis, we have elaborated two distribution models, one on the basis of real data of mercury vapour inmission in the area, and the second on the basis of a gaussian model that considers the facility as the unique source for the mercury vapours. Results indicate that emission from the facility is very low, producing in the surrounding area an insignificant increase in mercury inmission, that can be evaluated in 1-3 ng Hg · m-3. As a matter of fact, in the model obtained with real data the influence of this emission is negligible, and it seems to be controlled by soil contamination by the old mine dumps and related activities.Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEMinisterio de Ciencia e Innovación (MICINN)Programa europeo LIFE06 ENV.pu

Transferencia suelo-planta de elementos potencialmente tóxicos en el sector SO de la provincia de Ciudad Real

Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu

Creación y visualización de mapas prospectivos de mercurio mediante técnicas de inteligencia artificial

Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu

Sediment characterization of an artificial reservoir impacted by mining activity in the Almadén mercury district (Spain)

Los sedimentos del embalse Castilseras, ubicado aguas abajo en el río Valdeazogues en el distrito de Almadén, se recogieron para evaluar los contenidos en mercurio totales asociados con las aportaciones de sedimentos del río que provienen de las minas clausuradas. Se ha determinado el contenido en mercurio total así como otras propiedades físico-químicas de estos sedimentos. Los resultados muestran que el contenido en mercurio es elevado, y que se relaciona con el de los materiales de la zona, relacionados con la minería. Los sedimentos presentan un nivel de acidez significativo, son moderadamente salinos y tienen un tamaño de grano predominantemente limoso. El análisis estadístico indica que las concentraciones de mercurio están positivamente correlacionadas con el porcentaje en limo de las muestras. De los resultados obtenidos se puede concluir que el contenido en mercurio se va diluyendo aguas abajo del embalse y que éste está relacionado con la actividad minera, convirtiendo a Castilseras en uno de los embalses con mayor contenido en mercurio del mundo.Sediments from the Castilseras reservoir, located downstream of the Valdeazogues River in the Almadén mercury district were collected to assess the total mercury content associated with river sediment input from several decommissioned mines. A geochemical characterization, including the determination of total mercury content, were investigated using different physical and chemical techniques. The results obtained suggested that sediments are slightly acidic and characterized by high mercury, related to mining activities. In addition, sediments showed a silty texture and the electrical conductivity results showed moderate salinity, related to acid mine drainage (AMD) processes. The multivariate statistical analysis suggested that mercury content is positively correlated with the silt fraction in collected samples. In regard to the obtained results, we can conclude that Castilseras is one of the reservoirs with the highest mercury concentration, as a result of mining activities carried out in the zone. In this reservoir, the mercury content is diluted downstreamDepto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu

Geochemical Characterization and Trace-Element Mobility Assessment for Metallic Mine Reclamation in Soils Affected by Mine Activities in the Iberian Pyrite Belt

The geochemical characterization of the mine deposits and soils in metal mining areas is essential in order to develop an effective mine reclamation strategy. The determination of total potentially toxic element (PTE) content, together with the application of chemical extraction procedures, can give insight into the behavior of contaminants after the application of different mine reclamation solutions, as well as identify the areas where urgent action is needed. This work presents a practical application to the evaluation of the pollution potential of trace elements in soils affected by mining activities, to be used in metallic mine reclamation. The PTE behavior was assessed by single extractions in order to simulate four environmental conditions: PTE mobility under rainfall conditions, acid mine drainage, reducing conditions, and plant uptake. The spatial distribution of contaminants in the study area was evaluated by determination of PTE total content in soil samples. Trace elements with high natural mobility, such as Zn, appeared concentrated at water and sediment discharge areas, while As, Pb, and Cu contents were higher near the mine wastes. The results obtained after the extractions suggested that the highest PTE content was extracted in the complexing–reducing medium, due to the dissolution of secondary sulfates and Fe3+ oxyhydroxides and the subsequent release of PTEs associated with those mineral phases. Reclamation strategies applied in the study area should promote efficient water drainage, infiltration, and subsuperficial water circulation in order to maintain oxidant conditions in the soil. The methodology applied in this study may constitute a valuable tool to define the geochemical constraints in metal mining areas, as well as help to develop appropriate mine reclamation solutions