Title
Treatment of Emerging Road Runoff Contaminants in Green Infrastructure Systems
Abstract
Road runoff contaminants have been broadly implicated in the biological decline of urban aquatic ecosystems. In particular, 6PPD-quinone (N-(1,3-dimethylbutyl)-N’-phenyl-p-phenylenediamine quinone), the transformation product of a tire rubber antiozonant, is lethal to coho salmon at environmentally relevant concentrations and has been identified as the primary causal toxicant in die-off’s of coho salmon in B.C. and the U.S. Pacific Northwest. This talk will summarize insights from our “Salmonid Toxic Runoff Exposure and Mitigation (STREAM)” project, which aimed to assess the occurrence of 6PPD-quinone in the Lower Mainland of B.C. and the potential for green infrastructure systems to address these contaminants. We conducted field sampling of salmon-bearing streams throughout Metro Vancouver and conducted field tests of bioretention systems and retention ponds to assess 6PPD-quinone removal. We also completed lab-scale batch and column experiments to identify opportunities to enhance contaminant capture in bioretention systems. Together, our findings indicate the widespread occurrence of 6PPD-quinone in urban waters and demonstrate the effectiveness of bioretention systems to capture 6PPD-quinone.
Bio
Dr. Rachel Scholes is an Assistant Professor of Environmental Systems Engineering at the University of British Columbia. Her research focuses on trace organic contaminants in aqueous environments, including engineered and nature-based water treatment systems. She earned her M.S. and Ph.D. in Environmental Engineering from the University of California, Berkeley, and a B.S. in Chemical Engineering from Northwestern University, and completed a Fulbright Fellowship at the University of Otago, New Zealand. Prior to joining UBC, she conducted postdoctoral research at the United States Department of Agriculture. As an early-career faculty member, she has been highlighted as an Emerging Investigator by the Royal Society of Chemistry, was recognized as a Catalyst Scholar addressing the Climate and Nature Emergency at UBC, and has recently been appointed as a Wall Fellow for her contributions to addressing toxic road runoff contaminants.