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 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 70 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, the role of uranyl vanadates in controlling uranium concentrations in oxidizing environments, modeling and measurements of brine film thicknesses under confinement by supercritical CO2, experimentally identifying limitations of scaling predictions of capillary pressure-saturation relations for supercritical CO2-brine in porous media, and the potential acceleration of soil carbon sequestration through gypsum dissolution.

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-)

Patent and Invention Disclosures

  • Tokunaga, T.K., Y. Kim, and J.M. Wan. Aug. 20, 2013. Method of precipitating uranium from an aqueous solution and/or sediment.  Unites States Patent # US 8,512,572 B1.
  • Tokunaga, T.K., and D. Shuman. Aug. 23, 2010. A method to control low capillary pressure differences over arbitrarily high total pressures.  Lawrence Berkeley National Laboratory, Invention Disclosure IB-2931.
  • Tokunaga, T.K., J. Wan, Y. Kim, W. Dong, G. Shi. April 5, 2012. Supercritical CO2 and water microemulsions stabilized with refractory natural organic macromolecules.  Lawrence Berkeley National Laboratory, Invention Disclosure IB-3242.