Издатель: A.A. Balkema , Место издания: Lisse , Год издания: 2001

The investigation of inactive As-bearing tailings impoundments at the Khovu-Aksy minesite (Russia) have revealed the high concentrations of As in porewater of tailings solids and in their aqueous extractions as well as in adjacent soils. In this connection the laboratory experimental leaching of As-containing tailings were conducted. Three types of interacted solutions were used as the model natural and technological waters. No low-pH waters were observed after the experiments, pH varies between 8.3 and 9.1. These alkaline pH conditions are attributed to the effect of acid-consuming carbonate-mineral dissolution reactions, which are also indicated by increased concentrations of Mg and Ca. As a result, the mobility of heavy metals is negligible in comparison with As and may be assumed as essentially conserved in the solid phase. Predictions based on the observed data suggest that, in the absence of an effective remediated program, As release will continue to be an environmental problem.