Treatment of polymetallic ore tailing dump technogenic waters using artificial geochemical barriers

Relevance. It is imperative to mitigate the detrimental impact of drainage waters from polymetallic ore tailings deposits on natural surface waters of significant ecological and economic value, while concurrently reducing the carcinogenic risks to public health. Aim. To evaluate the possibility of reducing the concentration of carcinogenic elements and substances exceeding the normative values in the discharges of technogenic waters from the operating tailing dump by means of their purification using artificial geochemical barriers. Methods. Environmental monitoring, analysis of hydrochemical samples by ICP-MS and ICP-AES methods, assessment of the risk to public health posed by chemical substances, calculation methods. Results and conclusions. The paper presents the results of the experiment on purification of technogenic waters of the operating tailing pond of polymetallic ores of Dalnegorsk ore district on the model laboratory installation of artificial geochemical barriers. The essence of the study was to filter in dynamic mode hydrochemical samples of drainage water from the Central Concentrating Mill of Dalpolymetal in glass tubes through the proposed materials of artificial geochemical barriers – soil samples of the area under consideration (borozem and podbel), as well as a commercial sample of carbonate sorbent taurite. The analysis of hydrochemical samples of technogenic waters and leachate collected from the plant, carried out by ICP-MS and ICP-AES methods, demonstrated the overall efficiency of their purification from substances exceeding MAC values: Mn – more than 10 times, Cu – 9.5 times, Zn – 30.5 times. Assessment of carcinogenic risks for public health showed that in case of application of taurite sorbent their values are reduced up to 9.6 times – from the third to the second range of acceptability. Calculation of the hazard class of the barrier materials after treatment of technogenic waters allowed establishing the compliance of the samples with the IV class of hazard – low-hazard waste; the rate for their disposal as industrial waste is 835.6 rubles per 1 tone. For further large-scale experiments in relation to technogenic waters, the characteristics of bulk density and volumetric flow rate of all considered materials of artificial waters were determined and presented in the work.