Caracterización de los sedimentos del embalse de Castilseras en el entorno minero de Almadén

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 downstream.