2016 NGWA Groundwater Summit

Designing a Permeable Reactive Barrier for Groundwater Remediation using Water Treatment Residuals

Monday, April 25, 2016
Confluence Ballroom Foyer (The Westin Denver Downtown)
Christopher Walkons , Michigan Technological University, Houghton, MI, United States
Rupali Datta, Ph.D. , Michigan Technological University, Houghton, MI
Dibyendu Sarkar, Ph.D. , Stevens Institute of Technology, Hoboken, NJ
Rodney Chimner, Ph.D. , Michigan Technological University, Houghton, MI
Alex Mayer, Ph.D., PE , Department of Civil and Environmental Engineering, Michigan Technological University

Permeable reactive barriers (PRBs) present an attractive option for sustainable groundwater remediation. Not only is the barrier a passive system, but a PRB can often be constructed using reused materials. In this project we are designing a pilot-scale PRB for the removal of copper from groundwater. The reactive material for the barrier is the residual of coagulants used in drinking water treatment operations. The physical and chemical properties of this water treatment residual (WTR) have been studied to optimize PRB design. Batch reactor tests have shown that equilibrium sorption of copper to the WTR is best described with a Langmuir type isotherm and that the sorption capacity of the WTRs could allow a PRB lifetime on the order of decades. Kinetic batch and column tests have also been conducted to understand the significance of chemical and physical mass transfer limitations. A leaching test indicated that the WTR materials will not release contaminants into the environment. Constant head permeameter tests were performed with various mixtures of the WTR and an inert support material (pea gravel) to determine the ideal mix for matching the test site’s hydraulic conductivity. Additional work has been conducted at the site to determine aquifer depth, groundwater flow velocity, and contaminant concentration for designing the optimal dimensions and placement of the PRB.

Christopher Walkons, Michigan Technological University, Houghton, MI, United States
Chris Walkons is a student at Michigan Technological University in Houghton, Michigan. The research presented here is part of his work for a Master of Science in Environmental Engineering. Chris has a Bachelor of Science from Michigan State University in Park, Recreation, and Tourism Resources. He has worked for the National Park Service in the areas of visitor services, water quality monitoring, and natural resource management. He has also worked for the Western Upper Peninsula Health Department as an Environmental Health Technician doing alternative septic system inspections and water quality monitoring.

Rupali Datta, Ph.D., Michigan Technological University, Houghton, MI
Dr. Rupali Datta is an Associate Professor in the Department of Biological Sciences at Michigan Technological University, Houghton, Michigan. Previously, she was an assistant professor at the University of Texas at San Antonio. Her primary research interest lies in the application of plant biochemistry, molecular biology, and plant-microbe interactions in solving environmental contamination problems. She has worked on a broad range of soil and water pollution and remediation projects, including heavy metals and organics, with particular emphasis on understanding the biochemical mechanisms behind plant tolerance to toxic metals and organics in the environment.

Dibyendu Sarkar, Ph.D., Stevens Institute of Technology, Hoboken, NJ
Dr. Dibyendu Sarkar is a Professor in the environmental engineering program at Stevens Institute Technology, Hoboken, New Jersey. Previously, he was a professor and founding director of the environmental management PhD program at Montclair State University, New Jersey, and assistant and associate professor of environmental science and engineering, and associate dean of graduate studies and research at the University of Texas at San Antonio. Dr. Sarkar is an environmental geochemist, with research focus on environmental quality and remediation, risk assessment, and green technology development.

Rodney Chimner, Ph.D., Michigan Technological University, Houghton, MI
Dr. Rod Chimner is an Associate Professor of Wetland Ecology in the School of Forest Resources and Environmental Science at Michigan Technological University. He received his M.S. in Forest Hydrology from Michigan State University and his Ph.D. in Ecology from Colorado State University, both studying peatland ecology. Rod did his post-doctoral work as a Wetland Ecologist with the Institute of Pacific Islands Forestry, Hawaii, investigating carbon cycling of tropical peatlands in Hawaii and Micronesia. Rod’s current research focuses mainly on peatland carbon cycling and restoration. He currently has ongoing research projects in the Andes and Amazon of South America, Indonesia, the Rocky Mountains, and throughout the Upper Great Lakes region studying Northern White Cedar.

Alex Mayer, Ph.D., PE, Department of Civil and Environmental Engineering, Michigan Technological University
Dr. Alex Mayer is Professor of Environmental and Geological Engineering and Director of the Center for Water & Society at Michigan Technological University. Dr. Mayer’s teaching and research focuses on human-biophysical interactions in water systems, water resources management, watershed and modeling, and groundwater flow, transport, and remediation. Dr. Mayer has directed $5.6 million in externally funded research and has published more than 50 papers in the peer-reviewed literature. Dr. Mayer has served in editorial positions for several professional journals. Dr. Mayer has consulted for engineering companies, legal firms, and non-profit groups. He is a registered Professional Engineer.