In the frame of the French Code de l'environnement, two atmospheric measurement campaigns were undertaken during austral summer and austral winter at La Réunion Island in 2002, in order to evaluate the benzene concentration in the vicinity of two petrol stations. The two sites contained about 17 sampling points which were homogeneously divided around each of the petrol stations. This work was undertaken before the set up of vapour recovery systems during the filling and the discharge of tankers (stage I) and during filling of the private cars (stage II). The main objective of the study was to characterize the spatial distribution and the seasonal variation of the benzene and the toluene concentration in the vicinity of stationary emission sources, in two distinct regions of La Réunion Island. The results point out that the anthropogenic activities (stationary and mobile sources) are responsible of the benzene concentration variation at La Réunion Island. The model outputs show that benzene presents an inhomogeneous distribution and maximum concentration values in the immediate proximity of the Le Port petrol station. This characteristic is not observed around the Saint-Denis petrol station where the benzene distribution is quite homogeneous, with lower concentration levels. This is related to the conjugate effect of easterlies and land-sea breezes on this windward site. Meteorological data analysed in parallel with the benzene sampling indicate that the former have varied little during the two campaigns. We may thus assert that the "source effect", i.e. the anthropogenic emissions, is the predominant factor as compared to other processes (dynamical, deposition, scavenging) at these locations. On local scale, the benzene concentration in the vicinity of the petrol stations situated in urban areas, is higher by a factor of 3 to 12, as compared to values encountered in background/remote locations.
|Translated title of the contribution||Distribution of benzene concentration in the vinicity of petrol stations at la Réunion Island|
|Number of pages||13|
|Publication status||Published - 2005|
ASJC Scopus subject areas
- Atmospheric Science