Abstract:It is urgent to solve the problem of uranium concentration exceeding the standard in the groundwater after the retirement of the acid in-situ leaching uranium mining area. Therefore, exploring uranium species and its influencing factors is crucial for achieving efficient remediation. In this study, the groundwater of a decommissioned mining area in Xinjiang was taken as an example. The effects of temperature, pH, pe, Fe3+ concentration and Fe2+ concentration on the U species in groundwater and mineral saturation state were simulated by PHREEQC. The results indicated that the dominant chemical forms of U in groundwater are UO2SO4 and UO22+, accounting for 63.43% and 32.54% of the total U content. Secondly, the distribution of U species were influenced by groundwater pH, pe, temperature, Fe2+ concentration, and Fe3+ concentration. Among them, pe was the main controlling factor the valence state of uranium in groundwater. Thirdly, the effects of pH and pe on the saturation state of the minerals are greater, while the effects of temperature, Fe2+ and Fe3+ concentration are less, and the effects of pH and pe on the saturation state of uraninite, schoepite and Fe(OH)3 are the most obvious. Therefore, clarifying the influencing factors of U species in the groundwater of acid in-situ leaching uranium decommissioned mining areas can provide theoretical references for the efficient remediation of uranium contamination in groundwater.