Contamination risk assessment of the Transboundary Zeravshan River using chemical and isotopic studies

Parviz Normatov,Inom Normatov,O Chudaev,Y Kharaka,R Millot,O Shouakar-Stash,R Harmon

doi:10.1051/e3sconf/20199807021

Abstract

The results of chemical and isotope analyses of water of the Zeravshan River are presented. Results show that the low salinity of the river water in the upstream reach is formed mainly by water dissolution of minerals in natural rocks, i.e. the existence of a water-rock interaction process. The detection of heavy cations in the composition of the river water is due to their transport long distances in the form of microparticles by wind and accumulation in snow cover and glaciers. During the melting of snow and glaciers, and during rain events, pollutants are carried by streams, small rivers, and finally by Zeravshan River that distributes the pollutants over long distances.

Highlights

The problem of the water quality change and development of mechanisms to control river pollution continues to be of major concern for the region of Central Asia (CA) and all the states of the region
The problem of water quality in Transboundary river basins, such as the Zeravshan basin is compounded by the fact that up to now there is no network sharing of information regarding the quality of the waterways between the neighboring States of Central Asia
The results of chemical analyses of the Zeravshan River upstream, presented in Fig.1 shows that the concentrations of cations and anions of the Zeravshan river water do not exceed their maximum permissible concentration (MPC)

Summary

Introduction

The problem of the water quality change and development of mechanisms to control river pollution continues to be of major concern for the region of Central Asia (CA) and all the states of the region. The problem of water quality in Transboundary river basins, such as the Zeravshan basin is compounded by the fact that up to now there is no network sharing of information regarding the quality of the waterways between the neighboring States of Central Asia. The problem of water quality of the Zeravshan River is mostly associated with its pollution by wastewater of the Anzob Mountain-concentrating Combine - the mining enterprise for extraction and enrichment of mercury-antimony ores of the Dzidzikurut deposit [2,3,4,5,6]. The glacier retreated 88-94 m/year for the period 1991-2001 and its area decreased by 700.000 m2 and it is expected to decrease by 30-35% by 2050 [9]

Objective and methodology

Results and discussion

Conclusion