Acid Mine Drainage Contamination of the Ur Impoundment: Environmental Geochemistry

Irina Myagkaya,Maria Gustaytis,Bagai-Ool Saryg-Ool,Elena Lazareva,Ivan Kirichenko,O Chudaev,Y Kharaka,R Harmon,R Millot,O Shouakar-Stash

doi:10.1051/e3sconf/20199809021

Abstract

Water, particulate matter, and bottom sediments of the Ur impoundment used for fishing have been analyzed in terms of environmental geochemistry. The impoundment is located within the dispersion train of gold-bearing sulfide tailings at the Ur ore field and has been contaminated by acid mine drainage (AMD). The depth-dependent distribution of elements in the bottom sediments corresponds to (1) pre-mining, (2) early mining, and (3) post-mining (present) stages. Sediment enrichment in Cu, Cd, Fe, Pb, Zn, As and Hg depends on their speciation and migration patterns in water. The concentrations of many elements in water and bottom sediments exceed maximum allowable values. Hg occurring as the most toxic methyl compound poses the greatest hazard.

Highlights

The environment of residential and recreational areas has received progressively increasing recent attention [1]
Pollution can accumulate in dispersion trains of sulfide tailings left by mining and ore processing [3], which spread for tens of kilometers along rivers and store heavy metals and other contaminants [4]
Element contents in bottom sediments and in particulate matter were determined by AAS on a Solar M6 spectrometer, at the IGM SB RAS Analytical Center

Summary

Introduction

The environment of residential and recreational areas has received progressively increasing recent attention [1]. Pollution can accumulate in dispersion trains of sulfide tailings left by mining and ore processing [3], which spread for tens of kilometers along rivers and store heavy metals and other contaminants [4]. It is challenging to assess total contamination in ore fields where industrial pollution superimposes over naturally high enrichments in potentially toxic elements [5]. The cyanide wastes at the Ursk tailings site were dumped in 2 piles exposed to rainfall and floods that produce a dispersion train [6,7,8]. The wastes are drained by a natural creek which transforms into an AMD (рН 1.9) with high concentrations (ppm) of 3600 SO42-, >26 Al, 780 Fe, 0.63 As, 2.5 Cu, 11 Zn, 18 Cd, 110 Pb and 11.4 ppb Hg [7]. The aim is to estimate Cu, Cd, Fe, Pb, Zn, As and Hg contamination of the pond bottom sediments

Methods

Results

Conclusion