50 / 2023-12-27 16:34:02

Assessment of the Potential Hazard of an Abandoned Tailings Dump of Rare Metal Ores in the Kola Subarctic

tailing dump,loparite,radioactivity,rare earth elements

The development of the mining industry inevitably has a negative impact on the environment. Sources of soils, air and water bodies pollution can come from both operating enterprises and abandoned mines and tailings ponds. Samples of the surface layer (0-30 cm) of loparite ore enrichment tailings, stored in the tailing dump of an abandoned processing plant in the Murmansk region, were collected and studied. Engineering-geological characteristics (humidity, density, porosity and porosity coefficient) and the material composition of the waste were determined, sieve, X-ray phase and radionuclide analyses were carried out. The waste under study belongs to fine and medium-grained sands, the predominant fractions being 0.1-0.25 and 0.25-0.5 mm. The mineral composition of the waste is dominated by nepheline (up to 40%), microcline (up to 23%) and albite (up to 21%). The concentration of loparite in the -0.071 mm fraction was established - up to 0.86% versus 0.32% in the average tailings sample. A similar trend was noted for the calculated values of the specific effective activity of the fine fraction of enrichment waste (up to 793±98 Bq/kg), which exceeds this indicator for the average sample by up to two times. The specificity of stored enrichment waste suggests contamination of adjacent ecosystems with rare earth elements, which have recently been considered as new pollutants.