Abstract: The study was to understand the enrichment of uranium in the plants within the uranium tailings backfill area in the north of China. This study also provided a theoretical basis for the further study of the feasibility of phytoremediation technology in uranium mining area. Uranium content in plant and soil were measured with inductively coupled plasma mass spectrometry after collecting plant and soil samples in leaching location of mining area and in mine tailings backfill area. This study aimed at evaluation of plants tolerance and uranium enrichment ability, screening of plants, and further exploration for the use of phytoremediation technology. The uranium content in the underground part of the plants was found to be higher than aboveground part. Uranium was mainly concentrated in the roots, and the uranium contents in different parts of the plant from high to low were roots, leaves, stems, flowers and fruits. The uranium radioactivity in the root of Artemisia sieversiana was 64.26 Bq/kg in the leaching location. In the mine tailings backfill area, the uranium content in the same part was relatively low as 0.86 Bq/kg. The uranium content in the plant from the tailings backfill area was extremely low, and far less than that from the leaching area, and generally the uranium content in roots was greater than that in shoots. Uranium was mainly enriched in plant roots, and the contents in plant different parts from high to low were root, leaf, stem. Deep buried backfill of uranium tailing is proven to be feasible.

Key words: uranium tailing, uranium, phytoremediation