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Information × Registration Number 0216U002326, 0111U000206 , R & D reports Title Geochemistry of radionuclides in natural-technogeneous systems popup.stage_title Head Bondarenko G.N., Registration Date 16-02-2016 Organization The State Scientific Centre of Environmental Radiogeochemistry popup.description2 By experimental study of natural radionuclides (NR) speciation in the Prydniprovs'kyj Chemical Plant (PCP) tailings and their material composition it was found that 226Ra migration capacity is determined by the barium and soluble sulphate content and waste humidity. 210Pb migration ability is determined by carbonate and sulphate content in the wastes, as well as chemical environment alcalinity. 210Po migration ability is determined by the fine fraction content and the acid-alkaline conditions. The main ways of the evolution of the tailings waste composition were determined from the experimental data on tails composition and physico-chemical parameters of the wastes as well as published data on the mineral composition of uranium ores were processed at the PCP. A model of transformation of the waste material composition was developed. It was shown that the changes in mineral composition of tails should result in formation of new minerals with high sorption capacity. The pH values shift to near-neutral area, where sorption of the most radionuclides and heavy metals is maximal. That is, the barrier (sorption) properties of the waste should improve with time. It was found that the additional NR contributions from anthropogenic component of Tripillya TPP and Burshtyn TPP emissions are negligible in comparison with their content in soil and are not harmful. An increase in nuclide ratios 226Ra / 234Th and enrich of soil by radium isotopes, particularly 226Ra, are proposed as indicators of anthropogenic NR receipt. It was experimentally determined that modern soils and paleosoils from geological section Stari Kadaky (Dnipropetrovsk region) are allied in content of trace elements, so the contents of trace elements in paleosoils were proposed as reference values for estimation of the contamination level of soil in the region. Na-modified sorbents (industrially modified bentonite of Cherkassy deposit and laboratory modified zeolite of Sokirnitsa deposit) were found to be the most effective absorbents for Sr, Cs, Co and Mn on the equilibrium time and on the absorption degree. By the mathematical modelling method was determined that the degree of montmorillonite illitization should not exceed 1% under conditions of potential geologic repository for radioactive waste in Korosten pluton granite . It was shown that such decrease in the content of montmorillonite should not lead to significant decline of the absorptance for Cs, Ra, Sr, Pu, U. As result of the work the scientific bases for long-term forecasting of the geochemical behavior of natural and technogenic radionuclides in natural and technogenic systems in facilities for radioactive waste storage and disposal were developed inclusive of the transformation of the mineral component. Product Description popup.authors Бастригіна Т.М. Бондаренко Г.М. Висотенко О.О. Демченко Л.В. Дмитрієва С.В. Колябіна І.Л. Кононенко Л.В. Кузенко С.В. Манічев В.Й. Марініч О.В. Перкатий К.Є. Сиротенко Г.І. Суботін А.Г. Ярошенко К.К. popup.nrat_date 2020-04-02 Close