Mathematical modeling of distribution of the chemicals and the solid phase of tailings deposited on the mountain gorge slopes near the Fiagdonskoye tailings, North Ossetia-Alania

Abstract

Introduction. Tailings are a source of chemicals and finely dispersed solid tailings carried by air currents over considerable distances. Purpose of research. Creation of a predictive map of the concentration of chemicals and the solid phase of tailings carried by air currents in mountain landscapes, and a description of the pattern of their distribution along the slopes of mountain gorges near the Fiagdon tailing dump. With the help of a simplified aerodynamic model, the processes of aerosol dispersion of the solid phase of tailings and chemical elements in mountain landscapes from the Fiagdon tailing dump, located in the Kurtat gorge, North OssetiaAlania, Russia, are considered. These tailings contain lead, zinc, arsenic and other chemical elements. The mathematical model takes into account the complex mountainous landscape of the area, the characteristic wind roses, as well as the transport and sedimentation of the solid phase of the tailings. A forecast of the distribution of chemicals along the slopes of the Kurtat gorge, adjacent gorges and in the floodplain of the Khanikom-Don River (the right side tributary of the Fiagdon River) is presented, local wind roses are calculated, which are compared with field measurements and with measurements taken by meteorological satellites. The data of meteorological satellites of the American aerospace agency NASA are used: satellites Terra, Aqua, Geos, as well as the Copernicus global monitoring system for the environment and security of the European Space Agency. These data are averaged over an area of the order of 10 × 10 km or more, and the wind roses obtained on their basis characterize the study area on an average. The comparison of the simulations and these wind roses shows a qualitative agreement. Comparison of the wind rose measured by the weather station and the wind rose obtained from the computational model for this area shows good agreement. The results of the simulations show that the important factors determining the spatial distribution of the tailings and chemical elements deposited on the slopes of the solid phase in mountain landscapes are the features of the terrain, the characteristic direction of the wind speed and the atmospheric turbulence. The forecast of concentrations of the solid phase of tailings and chemical elements from the Fiagdon tailing dump in the mountain villages of Kakadur, Fazikau, Lamardon, Dargavs, Staraya Saniba, Karmadon, Verkhny Fiagdon is presented. Based on the results of simulations of aerodynamic processes in the atmosphere of the Kurtat Gorge, North OssetiaAlania, predictive map of the distribution of chemicals and the solid phase of tailings from source in the area of the Fiagdon is built. Chemicals and the solid phase of tailings are carried out in the Kurtat Gorge mainly in the eastern and northern directions, while in the settlement of Verkhny Fiagdon, the concentrations remain insignificant and lower than the MPC. The model can be used to estimate the concentration of chemicals and the solid phase of tailings carried by air currents in mountain landscapes and to describe their distribution patterns along the slopes of mountain gorges.