Environmental Isotopes in Studying Mining Groundwater Issues

Abstract

Investigations of potential mining and mineral processing impacts to groundwater can be enhanced through the use of environmental isotopes. Stable isotopes (Oxygen-18 and Deuterium) can help describe groundwater flow paths and can be particularly useful to map groundwater contamination plumes where background water quality masks the presence of contaminants. Radiogenic isotopes (Tritium and Carbon-14) can be used to age date different waters, which can be very helpful in determining groundwater flow paths.  They can also provide confirmation if flow connections exist between modern water sources (including mining facilities) and the groundwater in question.  Because isotopes are intrinsic to the water itself, they are not affected by chemical reactions between different waters or between the waters and the aquifer matrix. These properties of isotopes can greatly enhance the understanding of the local groundwater hydrology and reduce overall costs of site investigations. The authors describe the theoretical application of environmental isotopes and then review six mining property case studies where the authors successfully used isotopes in groundwater investigations.

Buck, B.W., and A. L. Mayo. Society of Mining, Metallurgy, and Exploration (SME) Annual Meeting, February 28 - March 2, 2005, Littleton, Colorado.