Predictive assessment of toxicants’ migration from technogenic gold-mining wastes (case study of the tailings management facility of Tokur mill, Amur region, Russia)

This article presents the results of predicting of the toxicants’ behavior in gold mining technogenic waste during their draining with seasonal precipitation (case study of the tailings management facility of Tokur Mill, Amur Region, Russia). The predictive assessment was made on characteristic basis of the following tailings management facility material: the geochemical composition, migration ability of elements in model experiments using atomic emission and mass spectral methods, calculation of acid-producing and acid-neutralizing potentials. It is estimated that the total content of geochemically mobile Pb and As forms in the tailings mineral matter makes up 85–92% of their gross content, Mn, Bi – 70–89%, Cd – 64–99%, Co – 50–65%, Cu – дo 46%, Zn, Ni, Fe, Sb – 30–36%, Mo – 17–20%, Cr – 5–7%. The substance of the tailing management facility has a high acid-neutralizing potential due to the carbonates in it (4–11%), which contributes to the neutral and slightly alkaline drainage flows formation. Under these conditions, the migration of Cd, Bi, Pb, Sr, Co, Cu, Ni, Zn, and Sb risk is low, and water migration of oxygen-containing As risk anions is very high, since the share of its mobile compounds in the tailings management facility material is 90–92%.