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| Fig. 1: Illustration detailing the in-situ mining recovery process (Courtesy of the NRC. Source: Wikimedia Commons) |
Uranium mining plays a pivotal role in nuclear energy production, yet its environmental consequences demand meticulous examination. This report conducts a quantitative analysis, delving into the complexities of land disruption, water usage, and greenhouse gas emissions associated with uranium extraction, specifically in-situ leaching.
In-situ leaching (ISL) is a method used for the extraction of uranium from underground ore bodies without physically removing the ore. [1] Instead, a leaching solution is injected directly into the ore deposit, where it dissolves the uranium and is then pumped back to the surface for further processing (Fig. 1). [2]
In-situ leaching is often considered more environmentally friendly than conventional mining methods, as it minimizes surface disturbance and reduces the generation of waste rock. However, it poses challenges related to groundwater management, potential for groundwater contamination, and long-term environmental impacts.
The methodology for assessing land disruption involves utilizing data from Schneider et al., which indicates a land intensity of 656 m2/tU for contemporary in-situ leaching (ISL) mining. [3,4] To express the average land disruption per kilogram of uranium extracted, we employ the following calculation using the total amount of uranium mined in the U.S. in 2022: [5]
| Average Land Disruption | = | Land Intensity × Uranium Extracted |
| = | 656 m2 tU-1 × 194 tU | |
| = | 1.27 × 105 m2 |
This calculation unveils the spatial impact of uranium mining, providing a basis for comparison with other resource extraction activities. It prompts us to ponder the long-term implications of land disturbance, both locally and globally and encourages a broader consideration of land use practices in the context of sustainable development.
To comprehensively understand water usage in uranium mining data from Schneider et al. is employed again. [6] This information allows for the calculation of water usage per unit of uranium extracted.
| Water Usage | = | Water Consumption Rate × Uranium Extracted |
| = | 1.6 × 107 L tU-1 × 194 tU | = | 3.1 × 109 L |
The assessment of water usage extends beyond the immediate extraction process, considering the broader implications for local ecosystems and communities. The amount of water used is extraordinary, but not unique in the world of metal mining.
Building on Norgate et al.'s data, the report calculates total emissions per unit of uranium extracted, considering the lifecycle-based emissions associated with nuclear power production: [7]
| Energy Content | = | 194,000 kg × 24 MWh/kg |
| = | 4.66 × 106 MWh | |
| Total Emissions | = | Emission Rate × Uranium Extracted |
| = | 34 kg CO2e/MWh × 4.66 × 106 MWh | |
| = | 1.58 × 108 kg CO2e |
The analysis of greenhouse gas emissions delves into the broader environmental implications of uranium mining. It highlights the trade-offs associated with nuclear power production, emphasizing the need for a nuanced understanding of emissions in the context of energy transition and climate change mitigation.
In conclusion, the report's methodology and contextual analysis provide a robust foundation for understanding the environmental impact of uranium mining. The combination of quantitative assessments and broader contextual considerations contributes to a nuanced and comprehensive evaluation of the issues at hand. More studies could delve deeper into the specific environmental and health impacts on local communities, incorporating social aspects into the analysis. Exploring advancements in extraction technologies could offer insights into further mitigating the environmental footprint. Additionally, interdisciplinary research that integrates environmental, social, and political perspectives could contribute to more holistic and sustainable solutions. A comparison with other extraction activities provides a broader context, emphasizing that while uranium mining poses challenges, it is not inherently more hazardous than other resource extraction processes. This broader context informs the interpretation of the quantitative findings.
© Autumn Parrott. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
[1] G. M. Mudd, "Critical Review of Acid in Situ Leach Uranium Mining: 1. USA and Australia," Environ. Geol. 41, 390 (2001).
[2] C. Hock, "In-Situ Leach Mining of Uranium," Physics 241, Stanford University, Winter 2017.
[3] Uranium Mining in Virginia (National Academies Press, 2012).
[4] E. Schneider et al., "A Top-Down Assessment of Energy, Water and Land Use in Uranium Mining, Milling, and Refining," Energy Econ. 40, 911 (2013).
[5] "2022 Domestic Uranium Production Report," U.S. Energy Information Administration, May 2023.
[6] Y. Ye et al., "Efficient and Durable Uranium Extraction From Uranium Mine Tailings Seepage Water Via a Photoelectrochemical Method," iScience 24, 103230 (2021).
[7] T. Norgate, N. Haque, and P. Koltun, "The Impact of Uranium Ore Grade on the Greenhouse Gas Footprint of Nuclear Power," J. Clean. Prod. 84, 360 (2014).
