CHEMICAL COMPOSITION AND GEOECOLOGICAL ASSESSMENT OF BOTTOM SEDIMENTS OF WATERCOURSES IN THE TOWNOF VOLSK (SARATOV REGION)

For many decades, two main watercourses in the town of Volsk (Saratov region) have been serving the transit function of sewage effluents to the Volgograd reservoir. Sampling of bottom sediments was carried out along the length of the Verkhnyaya and Nizhnyaya Malykovka watercourses in order to analyze the specificity of the chemical composition of alluvial formations under technogenic impact conditions. The fraction of technogenic particles (plastics, coal, paint, synthetic fibers, etc.) was 4-20%. In terms of chemical composition, alluvium is represented by silicites with varying degrees of clay content., Bottom sediments are characterized as clay silicites, with the maximum content of heavy metals and organic matter (based on the value of loss on ignition) in the areas where wastewater enters the watercourses. The most typical contamination is with zinc, lead, and barium. The overall level of technogenic pollution of bottom sediments is high and can be named considerable in the upper reaches of the Nizhnyaya Malykovka watercourse only. In order to improve the ecological status of the watercourses, a set of measures is needed, including reconstruction and the creation of new infrastructure facilities of the urban environment.