Ecological condition of mineral resource quarries under the influence of natural and anthropogenic factors

Open-pit mining of sand, clay, gravel, and other mineral resources in quarries is quite common in Ukraine. As a result of such activities, specific landscape systems are formed. After the cessation of quarry exploitation, stagnant water bodies are formed in their place, and targeted reclamation or natural succession leads to the formation of new ecosystems, which are considered important centers of local biodiversity conservation.

During the quarries’ exploitation, their conditions are determined mainly by technological processes. The intervention of external forces during the operation of quarries can cause significant ecological and economic consequences. The purpose of this study was to analyze the impact of natural and anthropogenic factors on the ecological state and functional characteristics of quarries. The object of the study was the quarry of the Ozerniansky marl deposit located in the Kyiv region. Clay and sand are mined here by the company "Slobozhanska Building Ceramics", which used these resources for the production of ceramic blocks and bricks at the local plant.

As a result of the occupation by the RF troops in February 2022, the plant ceased its activities, and the quarry operation was suspended. After the liberation of the Kyiv region in March 2022, it was not possible to resume the quarry operation due to the destruction of technological equipment and the lack of electricity. 50 m deep quarry began to fill with water and it resulted in the formation of the significant lake-type non-flowing reservoir in April 2022. Analysis of the factors influencing the current state of the quarry showed that the main ones are hydrogeological. The quarry is located in the feeding zone of watercourses flowing into the Irpin River, a tributary of the Dnipro River. It was found that the groundwater level in this area is relatively high. During the operation of the quarry, water was pumped out of it, so after the cessation of technological processes, its flooding was inevitable. However, the inflow of water was exacerbated by at least two circumstances. The first was climatic factors associated with precipitation. Short-term but intense precipitation in 2022-2024 not only affected the groundwater level but also intensified erosion processes on the slopes of the quarry. The second factor was the collapse of the dam that separated the Irpin River from the Kyiv Reservoir. It happened as a result of hostilities on February 26, 2022, and caused flooding of the Irpin River valley, which in turn increased groundwater pressure and affected groundwater flow in the quarry area. Calculations show that the impact of this factor is significant.

Restoration of productive quarry operations requires significant investments. Ongoing quarry monitoring indicates a slow succession of this system: the slopes of the quarry are overgrown with pioneer species, there are areas with tree species dominated by Robinia pseudoacacia, white poplar (Populus alba), black poplar (Populus nigra), and some others. At the same time, the main threat to the ecological state and operation of the quarry is hydrogeological factors.