Mapping Heavy Metal Pollution of Soils Affected by Metallurgical Point-Source Pollution Near Barcelona (Spain)

One of the most urgent tasks for atmospheric environmental protection is to monitor particle loadings in urban and industrial areas from point pollution sources. This allows the drawing-up of policies aimed at reducing emissions and the appraisal of their long-term effectiveness. Besides, mapping of the spatial distribution of pollution on contaminated surfaces is a primary prerequisite for further remedy and recovery efforts. This study presents results of magnetic mapping around a metallurgical plant near Barcelona. The aim of the study was to delineate highly contaminated areas and to discriminate them from areas relatively unaffected by this source. An enhancement in the concentration of magnetic particles in topsoil through this area has been observed. This fact is originated by anthropogenic magnetite transported through the atmosphere in a form of a plume which travels down-wind along the valley of the Llobregat River. <br>Optical microscopy on magnetic extracts shows the presence of small spherical particles (less than 20 mm) typical for the anthropogenic magnetic phases from high-temperature industrial processes. The spatial distribution of magnetic susceptibility of soil surface has been compared with the distribution of heavy metals in soil samples. High susceptibility values were found to coincide with increased heavy metal values.<br>