David_Shonnard_Scan

David R. Shonnard

Assistant Professor, University of California, Ph.D., 1991

Research

Bioremediation of Pollution

Naturally occurring microorganisms have been found which are able to degrade a spectrum of environmental pollutants, from crude oil to hazardous wastes, into relatively harmless products. Research in this area is aimed at isolating these microorganisms from environmental samples, growing them in bioreactors, studying their surface properties, enzyme stability, and transport characteristics, and finally designing remediation processes from the fundamental information. This research can be applied to designing clean-up of Superfund sites, industrial sites, and government research and military installations.

Environmental Transport Phenomena

The transport of chemicals in the environment, especially pollutants, is central to many activities of environmental engineers. These activities include determining the fate of agricultural and industrial chemicals in the environment, designing long-term containment of disposed hazardous wastes, estimating human exposure and risk from release of pollution, and designing environmental remediation processes. Research projects in this area will include studies of the partitioning of pollutants between various departments in the environment (for example, air and water, water and soils, air and soils). The ultimate goal is to construct mathematical models of the transport processes, which will ultimately lead to the design of remediation processes.

There is currently a Ph.D position available.

Publications

  1. D.R. Shonnard and R.L. Bell, "Benzene emissions from a contaminated air-dry soil with fluctuations of soil temperature or relative humidity, Environmental Science and Technology, (accepted, 1993).

  2. M. Lehning, D.R. Shonnard, D.P.Y Chang, and R.L. Bell, "an inversion algorithm for determination of upwind area source- strength from downwind concentration measurements," J. Air & Waste Management Association, (submitted, 1993).

  3. R.T. Taylor, A.G. Duba, W.B. Durham, M.L. Hanna, K.J. Jackson, R.B. Knapp, M.C. Jovanovich, J.P. Knezovich, N.N.Sha, D.R. Shonnard, A.M. Wijesinghe," In-situ bioremediation of trichloroethylene-contaminated water by a resting-cell methanotrophic microbial filter," Hydrological Sciences J., (in press, 1993).

  4. D.R. Shonnard, R.T. Taylor, C.O. Boro, M.L. Hanna, and A.G. Duba, "Bacterial attachment patterns created by horizontal injection into a two-dimensional aquifer-simulator; Applied to Methylosinus trichosporium OB3b," Water Reasources Research, (accepted, 1993).

  5. D.R. Shonnard, R.L. Bell, and A.P. Jackman, "The effects of nonlinear sorption on the diffusion of benzene and dichloromethane from two air-dry soils," Environmental Science and Technology 27, 475 (1993).

  6. D.R. Shonnard, R.T. Taylor, A. Tompson, and R.B. Knapp, "Hydrodynamic effects on microcapillary motility and chemotaxis assays of Methylosinus trichosporium OB3b," Applied and Environmental Microbiology, 58, 2737 (1992).