Abstract
The article is devoted to the study of hydrochemical indicators of surface waters of the Ilek River and large tributaries. The study was conducted based on the results of expeditionary observations in 2020-2021. Surface water samples were taken at key sites for chemical analysis of constituents. The scientific article describes natural and technogenic factors influencing the geosystems of the Ilek river basin. The paper reveals the dependence of surface water pollution on the impact of external technogenic factors. The study showed a direct dependence of surface water on the industry. In the upper part of the Ilek River basin, high concentrations of copper and zinc are observed in surface waters. In the middle reaches of the river Ilek exceeding the MPC by a factor of ten for chromium, iron, and boron is obviously associated with intense pollution of the production of the Aktuinsk chromium plant and the Aktobe ferroalloy plant. The work also describes the pollution of the tributaries of the Ilek River of the first and second order, associated with the mining industry in the regions.