Influence of bacteria on migration of uranium from uranium mining wastes

Our studies on bacterial diversity in waters, sediments and soils of different uranium mining wastes and repositories in Germany and in the USA demonstrated that these extreme environments are populated by dense groups of various bacteria, most of which are site-specific [14, 16, 17]. Recently we have found that these bacterial populations respond very vigorously to the addition of uranyl or sodium nitrate to their natural habitats [5, 6]. The predominant bacterial groups in the original, untreated samples, which contained about 26 mg U/kg, were rapidly replaced after the supplementations by bacteria, which were underrepresented in the untreated samples. The shifting in the structure of the natural bacterial community was dependent on the salt solution added, on the aeration conditions, and on the duration of the experiments...