Specificity of Composition and Properties of Umbozero Loparite Concentration Tailings

The article reports the research of composition and properties of loparite concentration tailings at the Umbozero plant closed in 1999. During the research, samples of tailings were taken in the surface layer and at depth, using the method of cutting ring. The geological and engineering properties of the tailings were investigated, and the sizing, chemical, X-ray phase and radionuclide analyses were performed. The research revealed heterogeneity in material constitution and properties of the test tailings. The mineral composition of the tailings is dominated by nepheline, and by K and Na feldspars. Loparite is detected by the X-ray phase analysis at one of the four test sites of the tailings pond, and its content increases in the fine fraction. The analysis of radionuclides shows the presence of radium and thorium in the test concentration tailings.