arctic – Mary Beth Leigh – Professor – University of Alaska Fairbanks

We’re working to assess the effectiveness and understand the mechanisms underlying phytoremediation (rhizoremediation), the use of plants and associated microbes, for cleanup of petroleum-contaminated soils in Alaska with a focus on rural communities. This includes advanced molecular genetic work on microbial communities, studies of biodegradation processes, plant natural product chemistry, contaminant analyses, and ecological assessments of contaminated sites. We’re also working closely with rural community members to find ways to improve local environmental self-determination, including identifying strategies that foster local engagement, employment, and economic benefit of cleanup activities.

By working closely with regulators (Alaska Department of Environmental Conservation), we initiated a long-term experimental/demonstration site in the rural community of Kaltag, AK, to remediate soil heavily contaminated with diesel that has been relocated from the schoolyard. If successful, this phytoremediation approach may be applied to many other sites across the state.

Funding for this research has been provided by the Alaska Department of Environmental Conservation, Alaska INBRE, USGS NIWR, the Czech Ministry of Education, the UAF BLaST Program, and the National Science Foundation.

As the risk of oil spills increases in Alaskan waters, there is a growing need to understand the biodegradation of petroleum as well as the fate and effects of oil spill response products. We are conducting laboratory incubation studies using Arctic (Chukchi Sea) and sub-Arctic (Prince William Sound) seawater as well as the Arctic benthos to assess oil degradation rates and to identify microbial taxa important to biodegradation. We are also investigating two spill response products on the National Contingency Plan (NCP) Schedule that are eligible for use in Alaskan waters and elsewhere: the chemical dispersant Corexit 9500A and Oil Spill Eater II (OSEII), a product marketed as an enzymatic biodegradation agent. Our goals include assessing the degradation of the major surfactant components of Corexit 9500A (with collaborator Jennifer Field of Oregon State University) and characterizing the composition and effectiveness of the lesser-known product OSEII. Because spilled oil can also become entrained in sediments, we are investigating the biodegradation of oil under aerobic and anaerobic conditions in Arctic sediment mesocosms as well. Using molecular microbial community analyses (e.g. 16S rRNA gene sequencing, metagenomics, and metatranscriptomics), we are characterizing shifts in community structure following exposure to oil and/or dispersants to identify taxa important to the biodegradation of petroleum and spill response products in the Alaskan marine environment. Through these studies, we aim to provide fundamental insight into Alaskan marine microbial ecology and to provide timely information to regulators, the oil spill response community, industry, and other stakeholders regarding the fate and effects of oil and spill response products in preparation for future oil spills.

These projects are funded by the Oil Spill Recovery Institute (Cordova, AK), Alaska INBRE, the Bureau of Ocean Energy Management (BOEM) Coastal Marine Institute and previously by private industry (Shell, ConocoPhillips, Statoil, Alaska Clean Seas) and a Fulbright Award to Thailand.

Current research on oil spill response chemicals is in collaboration with Co-PI Dr. Ursel Schuette, Research Scientist, Institute of Arctic Biology, UAF.

Former Ph.D student Kelly McFarlin

Ph.D. student Taylor Gofstein

PI Leigh with UIC Science Boat Captain Vernon Brower, Utqiagvik (formerly Barrow), AK

arctic Tag

Phytoremediation of petroleum-contaminated soils

Oil spills and spill response chemicals in the Alaska marine environment