Caracterización y dispersión del material aerotransportado en el entorno de la antigua zona de minería metálica de Cartagena-La Uniónimpactos y riesgos

Abstract

The general objective of this Doctoral Thesis has been to determine the presence or absence of material from non-confined mining and metallurgical residues present in the former mining district of Cartagena-La Unión, in the deposited and airborne atmospheric dust in the Mar Menor-Campo de Cartagena county, and its possible influence on the environmental health. In order to reach this objective, three types of samples have been sampled: atmospheric deposition, wind transport sediments and surface soils. Ten sampling stations were established. At each station, eight quarterly samples of deposition, five quarterly samples of wind transport sediments and two samples of superficial soils were taken. The sampling period for samples of deposition ranged from June 2011 to May 2013 and for wind transport ranged from March 2012 to May 2013. The average annual recorded total deposition level was 42.0 g m-2 year-1, higher than in most semi-arid areas. The total annual flows of total Zn deposition far exceeded the values of other areas and those established by national legislation. In contrast, Mn, Cd and Pb showed similar or lower values than those described in other mining areas of the Mediterranean Basin. The relationships between the measured parameters with others such as the distance to the mining-metallurgical waste were analyzed. Insoluble Cd, As and Sb showed in all samples types a higher concentration in the stations closest to the mining-metallurgical residues, which would indicate that their dispersion occurs from these materials. Another conclusion of this study was that the horizontal transport samples showed a marked behavior by the formation of saline crusts, so that during the dry periods larger amounts of all the elements were collected in their soluble phase. It has been established that the trace elements characteristic of the mining-metallurgical waste have been mobilized from the heart of this area to peripheral zones by means of wind transport at low altitude.