Exploring Spatial Variations in Dry Deposition and its Constituents with Respect to Industrial Facilities

Abstract As a consequence of industrial activities, significant quantities of settleable particulate matter (SPM) are transferred to surrounding areas. This study was carried out in Gijón (Spain), where industries coexist very closely with populated areas. The objective was to assess the variation in dry deposition (DD) levels with increasing distance from an integrated iron and steel plant, one of the potential sources of SPM emissions in the area. Sampling sites selected for this purpose were all located in the prevailing wind direction with respect to the factory and at varying distances: 1.3, 2.4, 4.0 km. DD levels and elemental composition were determined, and particle morphology was examined using scanning electron microscopy (SEM). DD levels decreased considerably as the distance from the steelmaking plant increased. Elements associated with steel production, particularly Fe and Mn, followed the same spatial trend as DD, contrasting with other elements that displayed a divergent distribution, such as Na (marine aerosol) and Pb and Zn (other anthropogenic sources). Morphological analysis confirmed the anthropogenic origin of specific particles, as some enriched in Fe and Ca. The results highlight the environmental burden endured by certain communities, which helps guide informed decisions about land use planning, particularly in areas close to major sources of fugitive emissions. These findings underscore the need to establish regulatory thresholds for SPM in ambient air.