Assessment of boron content changes in the surface water of the Ilek river valley (Aktobe, Kazakhstan)

Abstract

[EN] This article describe the problem of boron pollution of the surface water of the Ilek River valley (Aktobe region, Kazakhstan). The purpose of the article is to assess the dynamics of changes in the boron content in environmental objects (surface and groundwater) based on the materials of the operating in the field of monitoring systems and field research. The deterioration of the quality of surface and groundwater occurs from historical pollution, as well as from wastewater discharges from enterprises of the chemical, oil refining, machine-building industries and non-ferrous metallurgy. In Aktobe region, there is an imbalance between the ability of the natural environment to recover and anthropogenic load. Pollution of surface water is the cause of increased siltation of river, which has a harmful effect on the composition of bottom sediments, which constitute an integral part of the aquatic environment and the ecological system. In this situation, in the region, an excess of boron concentration approximately the Bestamak village by 50 times was constantly recorded in 2018, the MPC of boron in the reservoir in the area closest to the sludge collectors was exceeded by 143 times in 2017. The Ilek River pollution by boron is very acute, since boron is transported along the Ilek River and stored in the silts of the Aktobe reservoir, which is a recreational resource and a source of water supply for the Aktobe city. The high dynamism of boron leads to the fact that when it is roiled during releases from the reservoir, boron enters the lower reaches of the Ilek River, harming river organisms and the population, adversely affecting heredity. As a result of the study, exceeding the maximum permissible concentration of boron in the surface water of the Ilek River valley in unregulated flows was recorded.