Skip to Main Content U.S. Department of Energy
Biological Sciences

Research Plan & Schedule

Research Plan

Role of Microenvironments and Transition Zones in Subsurface Reactive Contaminant Transport

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). 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. The SFA will build on established areas of PNNL expertise in geochemistry, microbiology, and multi-scale modeling. The SFA consists of eleven projects involving twelve external collaborators that fall in the following science categories: i.) microbial ecology, ii.) molecular scale mechanisms, iii.) pore-scale coupled processes, iv.) reactive transport science, v.) multi-scale reactive transport models, and vi.) in-situ structures and reactive transport properties. Cohesiveness and integration will be achieved by focus on four SFA hypotheses and Hanford-relevant contaminant scenarios to enhance information upscaling, resolution of broader science issues, and Hanford impact. The SFA relies strongly on the Environmental Molecular Sciences Laboratory (EMSL) for fundamental science capabilities and the Hanford Integrated Field Challenge (IFC) site as an essential location for samples and opportunities for field scale research. 14.

Subsurface Science
Scientific Focus Area



Fundamental & Computational Sciences



Principal Investigators