Louis Joseph Thibodeaux
	Jesse Coates Professor Ph.D., Louisiana State University, 1968 Office: 158 ChE Building Telephone: 225.578.3055 E-mail:  thibod@lsu.edu

Encyclopedia Piece on Environmental Chemodynamics

"The Importance of Chemical Mass-transport Coefficients in Environmental and Geo-chemical Models", Society of Environmental Texicology and Chemistry GLOBE, Vol. 8, No. 4, July-August 2007, p. 29-31

Full-time Faculty. After eleven years as Director of Research of the hazardous waste/substance, EPA sponsored, centers Thibodeaux is now engaged full-time as a professor at LSU. He is active in teaching, research and service. He is particular proud of holding the title of Jesse Coates Professor in the College of Engineering. Professor Coates was Thibodeaux's Ph.D. thesis advisor and active in environmental chemical engineering. This association led in Thibodeaux's early entry into the field where it eventually became his all-consuming interests. Teaching undergraduates is a large activity. He routinely lectures the undergraduates heat and mass transport class, guides experiments in the junior laboratory course and coordinates the senior research course. Based on the second edition of his textbook entitled ENVIRONMENTAL CHEMODYNAMICS (Wiley, 1996) he offers a technical elective course each year of the same title. Professor Thibodeaux is a full member of the Graduate Faculty and guides a modest number of MS and Ph.D. students, graduating one or two yearly.

The Environmental Chemodynamics textbook was originally designed for use in an elective course for chemical engineering seniors. However, since its first appearance in 1979 it has enjoyed adoptions and use across a wide spectrum of engineering and science fields in addition to the target audience. Besides chemical engineering the most notable academic department uses are: civil-environmental engineering, soil science, geological and hydrogeological science, environmental chemistry, environmental science, geochemistry and public health 1996 to 2004. Known courses offering adoption total 48; and 12 are international universities. A solution manual is available upon request from the author. The textbook also enjoys widespread use by practicing professionals in consulting firms, research institutions, industrial organizations and governmental agencies. It is now being revised and updated; the third edition is scheduled to appear in the fall of 2006.

Environmental Chemodynamics, the study of the transport and fate of anthropogenic substances in the natural environment, is also the subject of Dr. Thibodeaux's research. In general, the projects are concerned with physical/chemical processes and models that describe transport of chemicals near the natural interfaces: air-water, water-sediment, and soil-air. His research blends laboratory and field data with mathematical modeling to yield a better understanding of the environmental behavior of hazardous chemicals produced, used and released as a consequence of all human activities. Besides the manufacturing industries these include the agricultural, silvicultural, mining and energy industries as well as the rural, urban and cities domestic and commercial hazardous substances.

Current research efforts are being focused on three key aspects of the remediation chemodynamics of bed-sediment contamination. One is the natural recovery processes of in situ bed-sediment in the aquatic environment of rivers, lakes and estuaries. The second is on the processes occurring with the surface soils formed from extracted (exsitu) dredged material. And the third is on the chemodynamics of that occur from the mud-clouds produced during dredging.

Challenging conventional wisdom. Prior to implementing a remediation technology such as in situ capping, dredging, in situ treatment it is necessary to fully understand and accurately quantify the on-going natural recovery processes. Recent findings on the significant role of bioturbation driven chemical release is challenging the conventional wisdom. Particle resuspension had traditionally been assumed to be the dominant process of transporting chemical mass from the bed to the water column. Storm events and other high water velocity evens do suspend, expose and translocate bed material for brief time periods. Although, bioturbation processes are slower they persist for long time-periods and typically contribute equal or more chemical release to the water column. Based in part on these findings riverine water quality models are being up-dated to reflect the combined particle resuspension, bioturbation and other significant processes. Confident chemical release projections for pre and post remediation must be based on theoretically sound chemodynamic process concepts and models. Published literature originating from the LSU Hazardous Substance Research Center concerning these release processes are references AEHMS 2002 Keynote Lecture (PowerPoint file).

Volatiles from dredged materials. The spoils produced in dredging contaminated bed-sediment must be properly managed. Typically the management options involve direct contact of the DM with the atmosphere. So-called confined disposal facilities (CDF) are large surface area disposal impoundments containing contaminated waters and solids dredged materials. Chemical volatilization to the atmosphere is an important biota exposure pathway for this DM management option. Chemodynamic models developed nearly a decade ago for the US COE are presently undergoing re-evaluation in our laboratory. With dredging being used as a primary remediation option quantifying the air releases from CDFs will need to be known with a high degree of certainty in order to make realistic exposure assessments. A recent literature review was focused on volatile releases from CDFs containing solid COE doc. connection.

Mud-cloud chemodynamics storm events. Mechanical and hydraulic dredges resuspend sediment particles into the water column. Fractions of the sorbed contaminants are solubilized prior to particle resettling. Definite engineering designs for these dredging operations with respect to quantifying chemical releases to water are predicated on understanding and quantifying the mud cloud chemodynamics. The quantities and size fractions of particles produced by dredge types and modes of operation is a key factor. This aspect is being investigated by Professor Don Hayes at Utah State University. The LSU HSRC efforts have been focused on measuring and modeling the chemical release fractions and their kinetics. Experiments with laboratory microcosms which mimic the mud cloud dynamics are providing the basic process information and yielding the quantitative algorithms needed for design. See literature citation numbers ( ) for details.

Recent Publications

• J. H. Pardue, W. M. Moe, D. McInnis, L. J. Thibodeaux, K. T. Valsaraj, E. Maciasz, I. van Heerden, N. Korevec, and Q. Z. Yuan, 2005, "Chemical and Microbiological Parameters in New Orleans Floodwater Following Hurricane Katrina," Environ. Sci. Technol, 39(22) pp 8591 - 8599
  
  
• LJ Thibodeaux, 2005, "A Recent advances in our understanding of sediment-to-water contaminant fluxes-The soluble release fraction," Aquatic Ecosystem Health and Management., Vol. 8, (1), p.1-9.
  
  
• L. Aguilar and LJ Thibodeaux, 2005, "A Kinetics of Peat Soil Dissolved Organic Carbon Release to Surface Water, Part 1, Laboratory Experiments," CHEMOSPHERE, Vol. 58, p. 1309-1318.
  
  
• L.J. Thibodeaux and L. Aguilar, 2005, "A Kinetics of Peat Soil Dissolved Organic Carbon Release to Surface Water, Part 2, A Chemodynamic Process Model," CHEMOSPHERE, Vol. 60, p. 1190-1196.
  
  
• MJ Erickson, CL Turner and LJ Thibodeaux, 2005, "A Field Observation and Modeling of Dissolved Fraction Sediment-Water Exchange Coefficients for PCBs in the Hudson River," Environ. Science and Technol., vol. 39, no. 2., p 549-556.
  
  
• LJ. Thibodeaux, H. Hulls, R. Raghunathan, KT Valrasaj, M. Costello, and DD
  Reible.l, 2004, "ALaboratory Simulation of Chemical Evaporation from Dredge-Produced Sediment Slurries," Environmental Engineering Science. Vol. 21. No. 6.p. 730-740.
  
  
• WJ Mills, ER Bennett, CE Schmidt and LJ Thibodeaux, 2004, "Approaches for obtaining quantitative vapor emissions estimates of PCBs and other SVOCs from contaminated Sites," Environmental Toxicology and Chemistry, Vol. 23, No. 10, pp.2457-2464.
  
  
• LJ Thibodeaux and VI Bierman, 2003, "The Bioturbation Driven Chemical Release Process," Environmental Science and Technology, July1, 253A-258A.

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