Graduate Research Assistant
University of Texas at Austin
Erin Berns is a Ph.D. candidate in her third year at the University of Texas at Austin, supervised by Dr. Charles Werth. She completed her B.S. degrees in Geological Engineering and Geology and Geophysics at the University of Wisconsin - Madison, and graduated with her M.S. in Environmental Engineering in Civil Engineering from the University of Illinois at Urbana-Champaign. She currently collaborates with researchers at UIUC and CDM Smith. Erin plans to defend her dissertation in December 2019.
STUDENT POSTER PRESENTATION
Reducing Chlorinated Ethene Flux from Low Permeability Zones: Evaluating the Contribution of Abiotic Reactions
Low permeability clays contaminated with trichloroethylene (TCE) can act as a long term source of chlorinated ethenes to groundwater resources. As TCE back diffuses from low permeability zones (LPZs) into high permeability zones (HPZs), it can be transformed by both biotic (reductive dechlorination) and abiotic reactions. The latter include reductive elimination, hydrogenation, and oxidation reactions with ferrous minerals. This work explores the contributions of abiotic reactions to the total flux of TCE transformation products into a HPZ using a biotic/abiotic flow cell experiment. Data from the experiment was used with a 1D diffusion-reaction model to fit kinetic parameters, which were then used to simulate field scale fluxes into HPZs. Abiotic transformation products comprised a small fraction of the flux in biologically active environments. But in electron donor limited systems or environments lacking a dechlorinating microbial community, abiotic reactions were shown to decrease the flux of chlorinated ethenes into HPZs.