Uranium speciation in coal fragments of radioactively contaminated soil

The shutdown of the Uranium Conversion plant and transfer of the territory to nonnuclear technologies requires management of large volumes of low-level radioactive waste. In this work, coal samples of contaminated soil collected at the territory of closed Sublimate Production Plant Angarsk Electrochemical Combine were analysed using X-ray absorption spectroscopy. By the comparison with reference samples, U oxidation state and speciation in coal fragments were determined. In contaminated coal samples, U is present as uranyl cation UO_2^2 + predominantly bound to natural organic matter. Understanding of U speciation in the most contaminated fraction of the soil is essential for low-level nuclear waste management. Graphical abstract