A model based on a substance transport equation for the reconstruction of polydisperse substance fallout from a continuous high – altitude sources is proposed. A numerical reconstruction of dust cover in the vicinity thermal power stations (TPS) 2 and 3 in the city of Novosibirsk has been carried out with the model and the available pollution monitoring data. The effects of wind direction changes in the atmospheric boundary layer on the formation of long-term aerosol substance fallout are estimated. Estimates of total of dust fallout from TPS 2 and 3 over the city are presented.