U.S. EPA Contaminated Site Cleanup Information (CLU-IN)

U.S. Environmental Protection Agency
U.S. EPA Technology Innovation and Field Services Division

Biogeochemical Interactions Affecting Bioavailability for in Situ Remediation: Session II - Bioavailability of Mixtures of PAHs, Chlorinated Compounds, and Metals

Sponsored by: NIEHS Superfund Research Program

Archived: Monday, May 13, 2019
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This webinar series will feature individual research projects funded by the NIEHS Superfund Research Program (SRP). In 2013, the SRP initiated a targeted research program to better understand how contaminants in the environment are affected by complex biological, geological, and chemical processes. By understanding these complex interactions, we are better equipped to optimize remediation strategies and, therefore, improve science-based decision making for site management, priority-setting, and remedy selection. The individual research project grants support problem-solving research on the mechanisms of biogeochemical interactions that may impact remediation of contaminated soil, sediment, surface water, or groundwater.

In session 2, we will hear from SRP-funded individual research projects at Virginia Institute of Marine Science, University of California, Riverside, and Colorado School of Mines.

Researchers led by Michael Unger, Ph.D., and Aaron Beck, Ph.D., at the Virginia Institute of Marine Science (VIMS) are developing new analytical techniques to help evaluate and quantify the mechanisms controlling the transport and the bioavailability of polycyclic aromatic hydrocarbons (PAH) at contaminated sediment sites. They have employed an antibody-based biosensor developed at VIMS that allowed rapid evaluation of the mechanisms controlling PAH transport at contaminated sediment sites saving effort and costs over traditional GC-MS based methods. Biosensor measured PAH in porewater was highly correlated to GC-MS analysis in split samples and was also correlated to benthic amphipod toxicity in laboratory tests. PAH concentrations in porewater samples were better predictors of toxicity than whole sediment PAH concentrations currently used for regulatory evaluation of remediation effectiveness. Future remediation plans at contaminated sediment sites that involve sediment removal and/or capping will need to address controlling the PAH flux to the aqueous phase. These new technologies allow this assessment to be accomplished more rapidly and economically than traditional methods. The technology has also been adapted for the rapid quantification of PAH concentrations in oysters and soils and is being developed as a potential tool for quick response during flood or oil spill events. For more information, please visit: Impact of Groundwater-Surface Water Dynamics on in situ Remediation Efficacy and Bioavailability of NAPL Contaminants

Jay Gan, Ph.D., and Daniel Schlenk, Ph.D., lead a project at the University of California, Riverside to develop a simple method for measuring and accounting for contaminant aging in risk assessments and remediation. They will apply the method to sediment samples collected from various depths (reflecting deposition at different historical times) and location (reflecting different sediment properties) at the Palos Verdes Shelf Superfund site off the Los Angeles coast. Sediments at this site contain high levels (up to 200 mg/kg) of DDTs and PCBs deposited from as far back as 60 years ago. For more information, please visit: Exploring the Importance of Aging in Contaminant Bioavailability and Remediation

Researchers led by James Ranville, Ph.D., at the Colorado School of Mines are developing and refining techniques - including environmental molecular diagnostics and stable isotope assays - used to detect, assess, and evaluate the bioavailability of metals that occur in mixtures and can be taken up by aquatic organisms, including nickel, zinc, copper and cadmium. They have tested these approaches in a metals-contaminated stream at the North Fork Clear Creek Superfund site in central Colorado. Stream remediation began in 2017 by lime-treatment of the major mining inputs. This project will improve knowledge on the risks posed by mixtures of contaminant metals and assist in evaluating remediation effectiveness. For more information, please visit: Investigating Biogeochemical Controls on Metal Mixture Toxicity Using Stable Isotopes and Gene Expressions

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A photograph of Michael Unger, Ph.D.Michael Unger, Ph.D., Virginia Institute of Marine Science ( or 804-684-7187)
Michael A. Unger, Ph.D., is an Associate Professor of Marine Sciences at the Virginia Institute of Marine Science. He is active in research, teaching, and advisory services related to environmental contaminant issues in Chesapeake Bay. His research interests include analytical method development including biosensors, contaminant partitioning behavior, toxicity studies to assess the effects of contaminants, and long-term fate studies to assess regulatory actions. He has studied polycyclic aromatic hydrocarbon contamination in the Elizabeth River, Virginia for over 25 years and recent research has focused on the development of antibody-based sensors for the near real-time analysis of environmental contaminants.

A photograph of Jay Gan, Ph.D.Jay Gan, Ph.D., University of California, Riverside ( or 951-827-2712)
Jay Gan, Ph.D., is a professor of environmental chemistry and a water quality specialist in the department of environmental sciences at the University of California, Riverside. He is a principal Investigator for the Exploring the Importance of Aging in Contaminant Bioavailability and Remediation SRP R01 grant and also completed an SRP R01 grant titled Development of Stable Isotope Based Methods to Predict Bioavailability of Hydrophobic Organic Contaminants in Sediments. His research interests include: environmental chemistry and toxicology of classic and emerging contaminants, including PCBs, DDT, PBDEs, PAHs, current-use pesticides and pharmaceutical and personal care products (PPCPs); transformation, transport, bioavailability, plant uptake and risk mitigation of organic chemicals in the environment; and method development for trace contaminant analysis. He has a B.S. and Ph.D. in environmental science from Zhejing University in China and completed postdoctoral work in agrochemicals at the UN-International Atomic Energy Agency's Laboratories in Austria, and postdoc work in environmental chemistry at the University of Minnesota.

A photograph of James Ranville, Ph.D.James Ranville, Ph.D., Colorado School of Mines ( or 303-273-3004)
James Ranville Ph.D., is a professor in the chemistry department at the Colorado School of Mines. He is the principal investigator for the Investigating Biogeochemical Controls on Metal Mixture Toxicity Using Stable Isotopes and Gene Expressions SRP R01 grant and also completed an SRP R01 grant titled Remediation Effectiveness for Mining Sites: Hysteresis and Metal Mixtures Effect. A major goal of his current research is to develop robust tools to determine the bioavailability of metals contaminated sites, before, during, and after remediation. Part of his research involves the role of colloids and particles in environmental processes. Another aspect of his research deals with aquatic toxicity tesing using D. magna. Dr. Ranville has a B.S. in chemistry from Lake Superior State University, an M.S. and Ph.D. in geochemistry from Colorado School of Mines and completed a Postdoc in water studies at Monash University in Australia.


A photograph of Karl Gustavson, Ph.D.Karl Gustavson, Ph.D., U.S. Environmental Protection Agency ( or 703-603-8753)
Karl Gustavson is the contaminated sediments team lead and chair of the Contaminated Sediments Technical Advisory Group (CSTAG) in the Superfund program at the U.S. Environmental Protection Agency (EPA). He previously worked for the Army Engineer Research and Development Center where he was stationed at EPA Superfund headquarters advising on contaminated sediment management. At EPA, he specializes in national and site-specific issues regarding contaminated sediment characterization, effects assessment, monitoring, and remediation, and provides technical support at multiple Superfund sites and Great Lakes Areas of Concern. The CSTAG provides formalized review of decisions at a subset of the largest, most complex, and controversial contaminated sediment sites. Dr. Gustavson is involved in several research efforts including on the development of procedures for documenting remedial effectiveness, novel methods to monitor contaminant bioaccumulation, and developing new approaches to reduce contaminant bioaccumulation in fish. Previously, he was a Senior Program Officer for the National Research Council (NRC) of the National Academy of Sciences where he served as the Study Director on reports reviewing Superfund site decision making, assessing the effectiveness of sediment remediation, and evaluating methods to improve chemical risk assessments. His Ph.D. is in Environmental Toxicology from the University of Wisconsin-Madison.

A photograph of Jean BalentJean Balent, U.S. EPA Technology Innovation and Field Services Division ( or 202-566-0832)
Ms Balent is on the staff of the EPA's Technology Innovation and Field Services Division where she has worked to collect and disseminate hazardous waste remediation and characterization information since 2003. Ms Balent manages the Clean Up Information Network website and actively supports online communication and collaboration resources available to EPA. She formerly worked with the US Army Corps of Engineers Environmental Engineering Division in the Buffalo District. Ms Balent was also a member of the SUNY-Buffalo Groundwater Research Group where she constructed and tested large scale models of groundwater flow. Ms Balent has also conducted research relating to the Great Lakes, environmental remediation, and brownfields re-development. She holds a Bachelor's degree in environmental engineering from SUNY-Buffalo and a Master's degree in Information Technology from AIU.

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