Air Pollution Characterization and Modeling of an Industrial Intermediate City

Abstract

Bahia Blanca is one of the most important port cities in Argentina, with a significant economic growth accompanied by air pollution caused by industrial and vehicle emissions. The ambient concentrations of gases like NOx, CO, NH3 and SO2 and concentrations of particulate matter have been measured by the local environmental authority between 1997 and 2008. The pollutants were monitored near an industrial complex, providing useful information to evaluate tendencies, to estimate the compliance of regulations and to evaluate the effects of control strategies, but giving only limited indication of spatial variation in concentration and source contribution to air quality. In order to complete the information provided by the monitoring data, pollutant dispersion was simulated with the CALPUFF modeling system. All industrial emissions were included in the model using detailed inventories requested by the local environmental authority. The mobile sources emissions were calculated according to EMEP/CORINAIR methodology, including road, air, railway and ship transportation. Residential and fugitive sources were also included in the simulation. Modeling results show that NOx, SO2, and NH3 concentrations were significant in the town of Ingeniero White, located 10 km SE of Bahia Blanca. CO higher concentrations however, were located downtown in Bahia Blanca since they are associated to road traffic. Simulated PM10 concentrations presented high spatial variability associated to the multiple sources of this pollutant. Although the urban center is strongly influenced by industries, their impact may not be significant due to the fact that all these emissions are subject to a bigger dispersion and dilution than traffic related emissions.