New Mexico Geological Society Annual Spring Meeting — Abstracts

The Jackpile Mine near Laguna Pueblo is located in the New Mexico uranium belt and was once the world’s largest open pit uranium mine. After the mine closed, it was reclaimed by the addition of soil on top of the mine tailings and leftover ore. This study aims to characterize the microbial communities in the soil, in relation to uranium concentrations and radioactivity levels. Soil was sampled aseptically, DNA was extracted and high-throughput metagenomic sequencing was performed at the National Center for Genome Resources. The resulting sequences give an overview of the inhabitant bacteria, eukarya and archaea. The results show a wide range of typical soil microbes, and also a strong representation from metal reducers, e.g., Geobacter spp. Importantly, the metal reducers include species bacteria that can reduce uranium from a mobile to an immobile state. Results suggest that the small amounts of uranium contamination ( 2.245 mg/kg to 15.191 mg/kg ) have selected for bacteria capable of reducing metals, including uranium.