Richardson, Susan D. 1438326 VanBriesen, Jeanne
Collaborative Research: Impacts of Energy Extraction and Coal-Fired Power Plants on Disinfection By-product Formation in Water
Increased energy extraction activities, including shale gas extraction and conventional oil and gas extraction, are resulting in high releases of bromide (and potentially iodide) to U.S. surface waters. New pollution controls being installed at coal-fired power plants are also resulting in high releases of bromide ion. These activities are presenting new issues for human and ecological health because when these high-bromide/iodide waters are chlorinated (a disinfection processes used in water treatment), they can result in the formation of highly toxic disinfection by-products, several of which may have adverse human health effects.
The proposed interdisciplinary research would comprehensively characterize and quantify brominated and iodinated disinfection by-products formed in source waters impacted by energy extraction and coal-fired power plant releases, determine potential human and ecological health risks, and use modeling to establish and quantify the linkage between impacted source waters and human exposures, and estimate maximum loadings of bromide and iodide that will minimize human risks.
While it is known that high levels of bromide and iodide can contribute to the formation of brominated and iodinated DBPs in chlorinated drinking water, even "conventional" disinfection by-products formed by reaction of chlorine with bromide, iodide, and natural organic matter (NOM) are not fully characterized, such that >50 % of the halogenated disinfection by-products remains unknown. This situation is even more complex when considering the possibility of additional chemicals used in energy extraction/utilization processes that are often unknown (particularly for hydraulic fracturing). No longer are the disinfection by-product precursors only from natural organic matter, and low levels of contaminants in domestic wastewater, but there are now additional precursors from these new energy extraction/utilization releases, which are largely uncharacterized. This is already resulting in significantly different exposures to both humans and aquatic organisms. Understanding the formation of these brominated and iodinated disinfection by-products and their potential human and ecological risks could ultimately inform decisions regarding control of bromide and iodide releases and what levels would be deemed safe.
