Groundwater Modeling, Bioavailability, and Remediation Technologies from EPRI's Arsenic Research

Groundwater Modeling, Bioavailability, and Remediation Technologies from EPRI’s Arsenic Research

 

Since 1993, the Electric Power Research Institute (EPRI) has conducted extensive research on the remediation of arsenic in soil and groundwater.  This work has been funded primarily by EPRI and the Southern Company, a large regional electric utility company.  Arsenic is of concern to the electric utility industry because of its presence in coal combustion residuals and related wastewaters; its widespread use as an herbicide, for example, at electrical substations; and its presence at legacy sites, such as manufactured gas plant (MGP) and other sites.  Arsenic is of concern to society at large because it is present at literally thousands of sites, and is considered recalcitrant, that is, both technically difficult and often expensive to treat.

The EPRI arsenic research program examined fate-and-transport, modeling, and bioavailability of arsenic, as well as multiple remedial technologies. An on-going technology assessment was performed, with periodic reports issued.  Technology demonstration projects included in-situ solidification and stabilization with chemical additives; advanced pump-and-treat (soil flushing and iron coprecipitation); electrokinetics; phytoremediation; hybrid ion exchange for water treatment; and in-situ chemical fixation, to prevent leaching to groundwater and to retard mobility within aquifers.  Highlights of each of these projects will be presented.  All of this work has significantly advanced the science of arsenic remediation.

The EPRI arsenic research program is documented in a dozen or more technical reports to date, two patents, and one patent pending.  Results of the program are shared at EPRI arsenic working group meetings, which are held semi-annually.