Modeling air quality impact of pollutants emitted by an oil/gas plant in complex terrain in view of a health impact assessment

The present study focuses on estimation of air quality impact of Centro Olio Val d'Agri (COVA) in view of a more comprehensive epidemiological study regarding the inhabitants of two small towns settled in the proximity of the plant. COVA activities involve different types of emissions, not all of them well-defined and controlled, as it is the case of fugitive emissions from flanges, valves, seals, and drains, and the case of atmospheric emissions from flares. We used the modelling system RMS (RAMS/MIRS/SPRAY) to estimate the ground level concentation of SO, NOx and CO due to the incineration of residues and to electric and thermic power generation. Simulations were run for one meteorological year. The comparison between meteorological predictions and measured data shows the capabilities of the model system in matching the wind field complexity along the valley. Spatial interpolation of measured H2S, proxy of the other types of emission, allowed to get a more detailed picture of the plant impact. Results suggest that the plant affects the inhabitants of the two towns differently. In addition, simulations show that the area impacted by the plumes is much larger than that of the two municipalities very close to the plant, suggesting the need to extend the monitoring area and to include in the health study also the population living in that area.