Mathematical Modelling of Dust Transfer from the Tailings in the Alagir Gorge of the RNO-Alania

Introduction. Mathematical modelling of the aerodynamics of mountain gorges is an actual means of studying possible man-made emissions in various meteorological conditions that increase the transfer of pollutants in the direction of densely populated areas. Aerodynamics and climatic conditions are unique for various mountain gorges. This requires a separate study for each specific case. The paper studies the distribution of dust aerosol from the Unal tailings dump, located near the village of Verkhny Unal (Alagir Gorge, RNO-Alania, RF), with south and south-easterly winds. With these wind directions, the dust of the tailings dump is carried by air currents in the north direction, towards Alagir. The aim of the study is to obtain a forecast for the surface concentration of dust with an increased content of lead, zinc and other elements near densely populated areas of the flat part of RNO-Alania.

Materials and Methods. The model takes into account the terrain, surface wind roses and dust deposition processes. The calculations were carried out for the case of neutral stratification and without taking into account the influence of seasonal factors using a mathematical model previously published by the authors.

Results. The model prediction of the dust concentration distribution obtained from calculations is shown. The frequencies and amplitudes of oscillations of unsteady jet streams in the cross section of the Alagir gorge are analyzed. Based on the data of satellite sensing of the Earth’s atmosphere, the frequency of winds leading to the transfer of dust in the direction of densely populated areas is estimated.

Discussion and Conclusion. The Unal tailings dump is a source of pollutants and over many years of its existence, soil contamination can be significant. Field studies of the soil in the Alagir area and, possibly, measures for its reclamation are necessary.

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