An integrated budget for selected pollutants for a major rural highway

A comprehensive study has been made of the fluxes of selected pollutants emitted from a major rural highway in NW England. Lead, cadmium, copper, the organic compounds of lead and 8 PAH species have been studied and their fluxes measured in bulk deposition samples in transects away from the road in the road runoff waters and its associated sediments and in soil profiles. Data collected in detail over one year indicate that, in the case of lead, 8% of the emitted metal is removed in the drainage waters 6% is deposited in the first 50 m adjacent to the motorway and approximately 86% is dispersed in the atmosphere away from the immediate vicinity of the road. Uncertainties in the emission rates of the other metals prevent such budget calculations being made. The amount of PAH removed away from the road environment by the atmosphere varies from approximately 99% for the lowest molecular weight compounds to approximately 70% for the heavier compound.