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Role of Microenvironments and Transition Zones in Subsurface Reactive Contaminant Transport


EMSL Project ID
34494

Abstract

The PNNL Scientific Focus Area (SFA) will resolve critical Hanford and basic subsurface science issues through integrated, multi-disciplinary, science-theme focused research on the role of microenvironments and transition zones in the reactive transport of technetium (Tc), uranium (U), and plutonium (Pu). Microenvironments are small domains within larger ones that exert a disproportionate influence on subsurface contaminant migration. They may be internal fractures or microbiologic niches within porous media lithic fragments; grain coatings, bio-films, or micro-colonies on larger mineral particles; or compact silt/clay stringers in gravel-dominated subsurface sediments. Transition zones are field scale features where chemical, physical, or microbiologic properties change dramatically over relatively short distances (e.g., 1 m). They exhibit steep, transport-controlled gradients of system controlling chemical species such as O2, H+, or organic carbon. Microenvironments and transition zones frequently dominate subsurface contaminant reactivity, with strong effects resulting from the coupling of chemical reaction, physical transport (advection, diffusion), and microbiologic processes. Past EMSP and NABIR research has documented the importance of these zones at the Hanford site.

The overall ten-year goals of the SFA are to develop: i.) an integrated conceptual model for microbial ecology in the Hanford subsurface and its influence on contaminant migration, ii.) a fundamental understanding of chemical reaction, biotransformation, and physical transport processes in microenvironments and transition zones, and iii.) quantitative biogeochemical reactive transport models for Tc, U, and Pu that integrate multi-process coupling at different spatial scales for field-scale application. Targeted contaminant chemical reaction and biotransformation processes include heterogeneous/biologic electron transfer, precipitation and dissolution, and surface complexation. The SFA will emphasize lab-based, coupled computational and experimental research using relevant physical/biologic models, and sediments and microbial isolates from various Hanford settings to explore
molecular, microscopic, and macroscopic processes underlying field-scale contaminant migration. It will also pursue the refinement of geophysical techniques to define, characterize, and map spatial structures and reactive transport properties of microenvironments and transition zones in the field. The SFA will partner with the PNNL Environmental Molecular Sciences Laboratory (EMSL) to develop molecular understandings of key processes, and the Hanford Integrated Field Challenge (IFC) for access to, and samples from subsurface environments where these zones exist and are important.

Project Details

Project type
Exploratory Research
Start Date
2009-08-31
End Date
2010-09-05
Status
Closed

Team

Principal Investigator

James McKinley
Institution
Pacific Northwest National Laboratory

Team Members

Zhangshuan Hou
Institution
Pacific Northwest National Laboratory

Carolyn Pearce
Institution
Pacific Northwest National Laboratory

Robert Ewing
Institution
Iowa State University

Piotr Zarzycki
Institution
Polish Academy of Sciences

Andrew Felmy
Institution
Washington State University

Sebastien Kerisit
Institution
Pacific Northwest National Laboratory

Thomas Wietsma
Institution
Environmental Molecular Sciences Laboratory

Tetyana Peretyazhko
Institution
Pacific Northwest National Laboratory

Allan Konopka
Institution
Pacific Northwest National Laboratory

Liang Shi
Institution
Pacific Northwest National Laboratory

Anderson Ward
Institution
Pacific Northwest National Laboratory

Mark Engelhard
Institution
Environmental Molecular Sciences Laboratory

Yilin Fang
Institution
Pacific Northwest National Laboratory

Donald Baer
Institution
Environmental Molecular Sciences Laboratory

Chongxuan Liu
Institution
Pacific Northwest National Laboratory

Glenn Hammond
Institution
Pacific Northwest National Laboratory

Mark Rockhold
Institution
Pacific Northwest National Laboratory

Scott Fendorf
Institution
Stanford University

Peter Lichtner
Institution
Los Alamos National Laboratory

James Fredrickson
Institution
Pacific Northwest National Laboratory

Timothy Droubay
Institution
Pacific Northwest National Laboratory

Zheming Wang
Institution
Pacific Northwest National Laboratory

Odeta Qafoku
Institution
Environmental Molecular Sciences Laboratory

Kevin Rosso
Institution
Pacific Northwest National Laboratory

John Zachara
Institution
Pacific Northwest National Laboratory

Ravi Kukkadapu
Institution
Environmental Molecular Sciences Laboratory

Bruce Arey
Institution
Pacific Northwest National Laboratory

Related Publications

Baer DR, AE Grosz, ES Ilton, KM Krupka, J Liu, RL Penn, and A Pepin. 2010. "Separation, Characterization and Initial Reaction Studies of Magnetite Particles from Hanford Sediments." Physics and Chemistry of the Earth 35(6-8):233-241. doi:10.1016/j.pce.2010.04.010
Belchik SM, DW Kennedy, A Dohnalkova, Y Wang, PC Sevinc, HJ Wu, Y Lin, HP Lu, JK Fredrickson, and L Shi. 2011. "Extracellular Reduction of Hexavalent Chromium by Cytochromes MtrC and OmcA of Shewanella oneidensis MR-1." Applied and Environmental Microbiology 77(12):4035–4041. doi:10.1128/AEM.02463-10
Boily JF, and KM Rosso. 2011. "Crystallographic controls on uranyl binding at the quartz/water interface." Physical Chemistry Chemical Physics. PCCP 13(17):7845-7851
Felmy AR, DA Moore, KM Rosso, O Qafoku, D Rai, EC Buck, and ES Ilton. 2011. "Heterogeneous Reduction of PuO2 with Fe(II): Importance of the Fe(III) Reaction Product." Environmental Science & Technology 45(9):3952-3958.
Ilton ES, JM Zachara, DA Moore, JP McKinley, AD Eckberg, CL Cahill, and AR Felmy. 2010. "Dissolution study of Metatorbernite: Thermodynamic Properties and the effect of pH and Phosphate." Environmental Science & Technology 44(19):7521-7526. doi:10.1021/es101619f
Liu C, J Shang, and JM Zachara. 2011. "Multispecies diffusion models: A study of uranyl species diffusion." Water Resources Research 47:W12514. doi:10.1029/2011WR010575
Shang J, C Liu, Z Wang, and JM Zachara. 2011. "Effect of Grain Size on Uranium(VI) Surface Complexation Kinetics and Adsorption Additivity." Environmental Science & Technology 45(14):6025-6031. doi:10.1021/es200920k
Skomurski FN, KM Rosso, KM Krupka, and BP McGrail. 2010. "Technetium incorporation into hematite (?-Fe2O3)." Environmental Science & Technology 44(15):5855-5861 .
T. Peretyazhko, J.M. Zachara, J.-F. Boily, Y. Xia, P.L. Gassman, B.W. Arey, W.D. Burgos. 2009. "Mineralogical Transformations Controlling Acid Mine Drainage Chemistry." Chemical Geology 262 (2009) 169–178. doi:10.1016/j.chemgeo.2009.01.017