Bioremediation of uranium-contaminated groundwater with an indigenous consortium under high-nitrate conditions

This study investigates the effects of nitrate exposure on the indigenous consortium mediated remediation of uranium-contaminated groundwater. Intermittent experiments reveal that high-nitrate concentrations hinder uranium reduction, whereas using glycerophosphate as carbon source, microbe could immobilize uranium by generating biomineralized precipitates with high crystallinity, and these precipitates exhibited better stability at high-nitrate concentration compared to those formed at low-nitrate condition. We also elucidated the mechanism of uranium removal by microorganisms under different conditions by analyzing changes in solution chemistry, products formed and microbial community structures. This work extends the scope for treating uranium-contaminated groundwater and is important for achieving long-term treatment of uranium contamination.