Establishing a Mechanistic Understanding of How Microbial Communities Remediate Groundwater Pollution at an EPA Superfund Site in the Denver Metropolitan Area

Date: 10/1/20
aerial shot of landfill
Principal Researchers: Chris Miller and Timberley Roane

Unit: Department of Integrative Biology

Project Abstract:
Rapid growth in the Denver metropolitan area has brought increasing population density adjacent to once remote municipal and industrial waste sites. This physical intersection of development and contaminated landfills has implications for drinking water quality, air quality, and other public health concerns. One such contaminated site is the former Lowry Landfill in Aurora, CO, a US Environmental Protection Agency Superfund site owned by the City and County of Denver. This site has long been recognized as a source of toxic 1,4-dioxane groundwater contamination. Since 2003, an above-ground bioreactor enabled by naturally present microbes has served as a nationally-recognized local success story in bioremediation. However, a surprising lack of understanding about the basic microbiology responsible for this bioremediation process has meant that this success has failed to replicate at other similar sites, and that changing groundwater contaminant profiles pose a risk to future operational success of the plant. 

The objective of this interdisciplinary research is to provide a genome-resolved mechanistic understanding of the biochemical metabolisms and microbial community ecosystem interactions that are responsible for 1,4-dioxane remediation at the Lowry Landfill bioremediation plant. Student researchers will use high-throughput DNA sequencing and computational biology to investigate the microbial mechanisms underlying successful bioremediation. Our overarching goal is that the new knowledge generated from this project will be applied immediately to improved management of the Lowry Landfill site, and in the future to improved management of similar sites with 1,4-dioxane contamination around the state and country.

Chris Miller Bio:
Chris Miller is an Associate Professor in the Department of Integrative Biology at the University of Colorado Denver.  His lab develops and applies bioinformatic and genome-enabled approaches to study microbial communities.  Recent publications from students in the Miller lab have applied high-throughput DNA sequencing and computational approaches to study the role of freshwater wetland soil microbes in cycling of the greenhouse gas methane, to study the evolution and diversity of the archaeal domain of life, and to investigate the role of environmental pollutants on the gut microbiome of animal hosts.  Dr. Miller’s work has been supported by the National Science Foundation, the US Department of Energy, and private foundations.  At CU Denver, Dr. Miller regularly teaches courses in Genomics and Bioinformatics, Biotechnology, and General Biology.  Dr. Miller received his PhD in Molecular Biology from the University of California Los Angeles, and did Postdoctoral research at the University of California Berkeley before joining CU Denver in 2012.

Timberley Roane Bio:
Dr. Timberley Roane received her Ph.D. from the University of Arizona in 1999.  Dr. Roane is currently an Associate Professor of Environmental Microbiology in the Department of Integrative Biology at the University of Colorado Denver.  Her research interests are in the discovery and elucidation of innovative microbial applications such as in ecosystem restoration, chemical mitigation, and energy production.  In collaboration with a variety of scientific, regulatory, and community organizations, her research has been sponsored by federal research agencies, such as the U.S. Department of Energy, the U.S. Environmental Protection Agency, the U.S. Forest Service, and the National Park Service.  Regularly publishing and presenting their research, Dr. Roane’s program combines conventional and advanced molecular and biochemical approaches to the study of microorganisms, and involves students from diverse backgrounds, educational levels, and scientific interests.  Dr. Roane is currently a director of the Environmental Stewardship of Indigenous Lands certificate program and is the faculty sponsor of the CU Denver American Indian Science and Engineering Society student organization.