Integrated measures for air pollution reduction in the Province of Milan

In the frame of air-pollution reduction policies to be evaluated by local decision-makers, economic costs and environmental benefits of a variety of short-, medium- and long-term actions have been envisaged and quantitatively assessed, with a particular attention to PM10 and NOX emission sources. To this purpose, proper indicators of economic parameters and emission factors have been selected, on the basis of data-bases available by public authorities. PM10 emission sources, calculated from local inventories, have been compared with the sources of PM10 concentrations in Milan estimated by Chemical Mass Balance model . Traffic, followed by residential heating, are the major contributions both to primary PM10 emissions and concentrations. Short-term interventions taken into consideration include reduction of inner temperature in residential and industrial buildings subjected to household heating, banning of fireplaces and biomass stoves, enhanced night-time washing of urban streets, speed limit reduction on highways, restrictions to the circulation of the most polluting diesel-cycle vehicles, increase and improvement of the bus fleets to favour the shift from private to public transport systems. Medium-term policies comprise support to car sharing and biking, PM-filters (DPF) adoption in road and off-road diesel vehicles, extension of road lanes for urban buses, energy efficiency improvement in residential buildings, DPF use in civil oil-fuelled boilers. As long-term measures, the study has analyzed the increase of urban district heating, new underground lines development, development of railways and intermodal passenger & goods transport systems, diffuse thermal and electric power generation by renewable energy-sources. For each action, a costs-benefits analysis to the integrated emissions reduction of primary PM10 and NOX over the whole territory of the Province of Milan has been applied, in order to get a pollutants abatement cost curve as a function of technical, social and regulatory constraints, thus drawing a list of priorities for the local policy maker.