Rodriguez Virginia G, Majumdar Ashabari, Meza Isabel, Corcoran Loretta, Pierson Amanda, Gagnon Kaelin, Cano Caitlyn, Ali Abdul-Mehdi S, Shuey Christopher M, Jojola Gregory, Tan Wanpeng, Aprahamian Ani, Cerrato José M, Burns Peter C
Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States.
Department of Physics and Astronomy, University of Notre Dame, Notre Dame, Indiana 46556, United States.
Environ Sci Technol. 2024 Aug 13. doi: 10.1021/acs.est.4c01257.
Surface water and sediments from the Jackpile mine, St. Anthony mine, Rio Paguate, Rio Moquino, and Mesita Dam areas near Pueblo of Laguna, New Mexico, were analyzed for Ra and U using gamma (γ) spectroscopy and inductively coupled plasma mass spectroscopy, respectively. Activity ratios for Ra/U for solid samples range from 0.34 ± 0.13 to 16 ± 2.9, which reflect uranium transport and accumulation (<1), relatively pristine material in secular equilibrium (1), and removal of uranium by weathering (>1). Concentrations ranging from 80 to 225 μg L U were detected in unfiltered water samples near the Jackpile mine. Water samples upstream and downstream from the mine contained concentrations ranging from 12 to 15 μg L U. Water samples collected from the North Pit standing pond in the Jackpile mine contained as much as 1560 pCi L of Ra, and passing the water through a 0.2 μM filter did not substantially reduce the activity of Ra in the water. Th and Ra are in secular equilibrium in this water, while radon gas was lost from the water. The results of the current study provide insight into the distribution of U-series radionuclides in the Pueblo of Laguna area, including detection of high levels of radioactivity in water at some locations within the Jackpile mine.
分别使用伽马（γ）光谱法和电感耦合等离子体质谱法，对新墨西哥州拉古纳普韦布洛附近的杰克派尔矿、圣安东尼矿、里奥帕瓜特河、里奥莫基诺河和梅西塔大坝地区的地表水和沉积物进行了镭和铀分析。固体样品的镭/铀活度比范围为0.34±0.13至16±2.9，这反映了铀的迁移和积累（<1）、处于长期平衡状态的相对原始物质（1）以及因风化导致的铀去除（>1）。在杰克派尔矿附近的未过滤水样中检测到铀浓度范围为80至225μg/L。该矿上游和下游的水样中铀浓度范围为12至15μg/L。从杰克派尔矿北坑积水池采集的水样中镭含量高达每升1560皮居里，并且让水通过0.2μm的过滤器并没有显著降低水中镭的活度。钍和镭在这种水中处于长期平衡状态，而氡气从水中逸出。当前研究结果有助于深入了解拉古纳普韦布洛地区铀系放射性核素的分布情况，包括在杰克派尔矿内某些地点检测到水中的高放射性水平。
