Using basic hydrophysical characteristics of soils in calculating capacity of water-retaining fertile layer in recultivation of dumps of mining and oil industry

Abstract

Large volumes of solid waste consisting of empty rocks, slags and slurries characterize active development of the mining, metallurgical and oil-producing industries. To accommodate them, a large area in the immediate vicinity of the production is required. Filled to capacity dumps require immediate reclamation to prevent erosion or swelling of solid waste. Lack of protection against external influences (wind and rain) will inevitably lead to deterioration of the ecological situation in the regions where mining or processing of minerals is concentrated. The reclamation includes the stage of formation of a fertile layer on the surface of the dumps, providing favorable development of perennial grassy vegetation. The fertile layer should have a good water-retaining capacity, preventing the penetration of water deep into solid waste and wash out harmful substances. Each climatic zone requires a layer of vegetable soil of a certain thickness and particle size distribution. To define these indicators, a software product was developed that allows one to simulate water-physical properties of bulk soil with the main hydrophysical characteristic. The program can calculate the composition of soil with the necessary parameters of granulometric composition. It is mathematically and experimentally established that for conditions of a forest-steppe zone of Western Siberia, formation of the soil layer consisting of the fertile earth not less than 32 cm thick is required; sand or crushed stone – 10-20 cm and the shielding layer of clay is no more than 30 cm thick. The creation of such soil will reliably retain atmospheric precipitation, and the shielding layer will prevent the rise of water and harmful substances to the surface.