Hydrogeological protection of the buchak-kaniv aquifer complex in the central part of Dnipro-Donetsk artesian basin from possible technological contamination

Abstract

Formulation of the problem. Every year, the problem of studying the ecological state of drinking groundwater becomes more and more acute, as the reserves of ecologically clean groundwater is becoming more and more depleted. At the same time, at the time of significant influence of technogenic factors on the quality of drinking groundwater, there is an urgent need for a more detailed assessment of the protection index of aquifer complexes promising for water use purposes. The purpose of the article. The main purpose of the research is to show the degree of modern hydrogeological protection of one of the strategic reserves of drinking underground water in the region – Buchak-Kaniv aquifer complex – in the area of its greatest distribution and use – the central part of Dnipro-Donetsk artesian basin from possible contamination of water that lie above. Corresponding trends in protection changes during the long period of time (55 years) within the territory of work were also traced. Methods. Taking into account the hydrogeological and lithological features of aquifer complexes and waterproof rocks in the interior of the subsoil, as well as on the basis of previous research by scientists, a multi-factor, adapted to these conditions, methodology for carrying out the research was developed. The methodology includes the definition of both static and dynamic components of the protection index. Calculations and graphic constructions were made for 2 periods of time – 1960 and 2015. Results. The peculiarities of the hydrogeological protection of the aquifer complex within the territory of works during these periods were analyzed and relevant trends in changes in the indicator over the 55-year period have been traced. It has been determined that the territories of areas with unprotected and conditionally protected underground water expanded, and protected areas – on the contrary, decreased. The largest changes occurred in the areas affected by water intakes of large cities in the region. The reasons for these processes are presented, the main of which is an anthropogenic factor. Scientific novelty and practical significance. This methodology in assessing the protection in this region has been used for the first time. The obtained results of the research should be used to develop recommendations for the ecological protection of drinking groundwater in the region. This method of work can be used to determine a hydrogeological protection index of other pressure aquifer complexes in similar conditions.