Superfund Research Program
Arsenic, Iron, Sulfur and Organic Carbon Speciation and Their Impact on Groundwater Arsenic
At least 100 million people are exposed to unsafe levels of arsenic (As) in drinking water. Understanding the causes of, and solutions to, this extensive problem, requires detailed characterization of the systems that are affected. This project examines the combination of chemical, biological and physical processes that affect the distribution of As contamination, and how this distribution of As can change in response to human disturbance. Over the last year, this project’s research team has (1) developed an improved field method for measuring and collecting arsenic concentrations on mobile devices (Haque et al., 2017), and (2) used this method in combination with extensive field sampling to document the heterogeneity and extensive changes in As concentrations in areas subjected to extensive groundwater pumping (Mozumder et al.). Researchers also (3) developed a method of using the radiocarbon signature of the phospholipid fatty acids extracted from sediment samples (Whaley-Martin et al., 2016) to help understand the active biological processes that affect As levels in aquifers. Currently, the research team is developing parallel efforts to concurrently analyze RNA with DNA to link active microbial populations and metabolisms in aquifers (Gnanaprakasam et al.; Mailloux et al.). Finally (4) basic research is being applied from the above studies to improve methods of stimulating indigenous autotrophic bacteria to produce magnetite and thereby remediate groundwater with sediments from Dover landfill (Sun et al., 2016). These efforts offer the potential to improve sustainability and access to safe groundwater, and to remediate Superfund sites much more cost-effectively and rapidly than is practical with current technologies.