In order to evaluate the net contribution of the petrol station to the ambient benzene concentrations, the urban
background concentration, measured by passive samplers and the contribution of the roads, estimated with both the
COPERT and the linear source model CALINE 4, were deduced. Validation and optimization of the modeling system
COPERT and CALINE4 was done in advance to ensure the reliability of the results. It seems that petrol stations have a
significant contribution to ambient benzene concentrations in their vicinity.