TRACING THE IMPACTS OF FOSSIL FUELS PRODUCTION ON THE QUALITY OF WATER RESOURCES IN THE UNITED STATES

For decades, coal has been the primary source of fuel for electricity production in the United States. Yet, over a century of coal mining and combustion has created a legacy of water pollution: seepage of metal-rich acid mine drainage into watersheds, contamination of streams by selenium in effluents from surface mountaintop mining, and effluents enriched in arsenic, boron, and other toxic metals from hundreds of coal ash ponds that leak to associated water resources across the nation. Since the mid- 2000s horizontal drilling and hydraulic fracturing developments have spurred exponential growth of shale gas well exploration across the United States. Yet, recent scientific findings have shown evidence for stray gas contamination of shallow groundwater associated with shale gas development and contamination of surface water and river sediments from disposal or leaks of wastewaters generated during shale gas production, which are often highly saline, toxic and radioactive.

Tracing the impacts of these contaminants is challenging given the presence of naturally occurring contaminants in some of these areas. This presentation presents a diagnostic geochemical “tool-box” that enables scientists to delineate and monitor contaminants’ sources originated from fossil fuels production. The integration of inorganic chemistry and multiple isotopic tracers such as boron, strontium, radium and inorganic carbon provides a novel methodology for identification of the specific contaminants’ sources and reconstruct their pathways in the environment. While low-cost coal and new shale gas reserves are vital for enhancing US energy security, the direct and indirect effects on the environment might have significant long-term implications for the ecological systems and human health.