Earth Sciences Division (ESD) Department of Energy (DOE) Lawrence Berkeley National Laboratory (LBNL)

Earth Sciences Division Staff: Tetsu K. Tokunaga

Tetsu Tokunaga

Tetsu K. Tokunaga

Senior Scientist

Hydrogeology Department

 

 

Phone: 510-486-7176

Fax: 510-486-5686

Email: tktokunaga@lbl.gov

Biographical Summary

Tetsu Tokunaga is a senior staff scientist in the Earth Science Division of Lawrence Berkeley National Laboratory, studying the physicochemical basis of environmental transport processes.  While conducting his graduate studies on gas diffusion in porous media at the University of California, Berkeley, he began working at LBNL on problems of unsaturated flow and transport from uranium mill tailings, and on reactive transport of selenium in contaminated wetland (Kesterson Reservoir).  Upon graduation, he continued at LBNL conducting laboratory and field based studies on soil/geologic transport problems. In addition to his research at LBNL, he taught soil physics courses at the University of California, Berkeley. He currently has over 60 publications in peer-reviewed journals.

Research Interests

Tetsu Tokunaga’s research combines soil physics with related fields of hydrogeology and biogeochemistry.  His research accomplishments include identifying the general free-path basis for gas diffusion in porous media, the importance of water film hydraulics in multiphase fluid flow, Boltzmann flux distributions in unsaturated rocks, limits for capillary hysteresis, the permeability-sorptivity scaling relation, the unsustainability of reduction-based remediation of uranium contamination, and the possibility of uranium recovery from contaminated groundwaters through precipitation of uranyl vanadates.  He has developed methods for direct measurements of diffusion-limited precipitation of selenium, chromium and uranium in variable redox sediments; developed and validated methods to predict hydrologic and geochemical cycles in vernal pools/wetlands; and developed innovations in tensiometric water potential measurements.

Education

  • Ph.D.,  1986, Soil Science, University of California, Berkeley.  The temperature dependence of gas diffusivities in porous media.
  • B.A.,   1979, Soil Resources, University of California, Berkeley.

Professional Experience

  • 2001-present: Senior staff scientist, Earth Sciences Division, LBNL
  • 1993-2001: Staff scientist, Earth Sciences Division, LBNL
  • 1990, 1992:  Lecturer, Department of Soil Science, University of California, Berkeley
  • 1988 -1993: Scientist, Earth Sciences Division, Lawrence Berkeley National Laboratory

Service

  • Water Resources Research, associate editor (2009-)
  • Vadose Zone Journal, associate editor (2008-)
  • LBNL, Professional Staff Committee (2008-)
  • Earth Sciences Division, Professional Staff Committee (2001-)