A STUDY OF THE HYDROGEOLOGICAL REGIME OF THE NATURAL AND TECHNICAL GEOSYSTEM: THE CASE STUDY OF THE DNIESTER GES

Abstract

The primary objective of the study is to analyse changes in the hydrogeological regime before and after the facility's commissioning, taking into account the impact of human activity on water resources. To solve this problem, it is necessary to regularly measure groundwater levels. This process was carried out by systematically measuring the water level in piezometers for the period from 2010 to 2023 with a frequency of twice a week. To achieve this goal, it was necessary to analyse the geological structure and hydrogeological characteristics of the unconfined aquifers in the soil strata, as well as to investigate the permeability of rocks. Changes in the hydrogeological regime can be caused by both rock compaction due to changes in the stressed deformation state and activation of geodynamic processes, which, in turn, contribute to drainage through faults in the rock mass. The research in the article allows us to more accurately assess changes in the hydrogeological regime of the rock mass, in particular, in the reduction of the water-holding capacity of a certain horizon. The study reveals the possible causes of these changes, such as soil compaction and activation of geodynamic processes, and indicates potential consequences for the hydrogeological environment and water use, when planning and operating other energy facilities in similar conditions. The practical significance of this study is that it helps to understand changes in the hydrogeological environment and their potential impact on water resources. This is important for the development of effective strategies for managing water resources individually and preserving ecosystems in general. Studies indicate that during the period from 2010 to 2023, significant changes occurred in the hydrogeological regime of non-pressure horizons #1 and #2. The analysis of groundwater levels indicates that in certain local areas there is a decrease in the water level, which indicates the degradation of the soil massif. These changes may be related to the effects of drainage, which caused the disruption of structural bonds in soils and their transition to a loose state. In the case when the clay soil, which serves as a waterproofing layer for non-pressure horizon No. 1, loses its waterproofing properties, it can be explained with the help of the Coulomb-Mohr law, which reveals the dependence of the angle of internal cohesion (φ) on the coefficient of internal grafting (С) in soils. In simple language, when structural bonds are destroyed in clayey soils, the filtration coefficient increases [30, p. 240; 15, p. 223; 34, p. 170; 28, p. 2]. The potential cause of the destruction of structural bonds in the soil is described in works [36, p. 3]. Therefore, it can be concluded that the dynamics of groundwater levels indicates the influence of hydrogeological processes on the physical properties of the soil environment, which is important for the further management of water resources and the preservation of ecological sustainability of the region. The practical significance of this study is that it helps to understand changes in the hydrogeological environment and their potential impact on water resources. This is important for developing effective strategies for managing water resources separately and preserving ecosystems as a whole. For example, it is possible to develop models that will predict soil deformations depending on the level of groundwater, which will avoid possible destructive consequences for infrastructure and construction objects. Such data can also be used to improve hydrotechnical structures and determine optimal water resources management strategies in conditions of changing hydrogeological regime. Keywords: Geoecology, constructive geography, geosystems, river-basin systems, river-valley landscape, river natural and technical systems, landscape technical systems, landscape engineering systems, GIS technologies, Dniester PSPP, oolitic limestone, piezometer, aquifer, piezometric surface, soil base, infiltration, Neogene, aquifer.