Record Search Query:
R-UNSAT Mathematical Model for Simulating Transport of Volatile Organic Compounds
Entry ID: 02-usgs-R-UNSAT-00
Abstract: The Galloway research team has developed and documented three computer models
(AIR2D, AIR3D, and R-UNSAT) for simulating flow and transport in the
unsaturated zone that are available to the public. These models were funded
by the Toxics Substances Hydrology Program. The computer codes are written in
Fortran F77 and run on a variety of computer systems, including mainframe and
personal computers, ... with only minor adaptations. The programs are written in a
modular structure which facilitates modifications to the source code. Whenever
these modifications are made, the program must be recompiled with a Fortran F77
compiler to incorporate the changes in the executable versions of the program
code. The commands needed to link and compile the program depend on the type
of compiler being used.
R-UNSAT is a computer model for the simulation of reactive, multispecies
transport in a heterogeneous, variably-saturated porous media. R-UNSAT was
designed for simulating transport of volatile organic compounds in the
unsaturated zone from point and nonpoint sources, but can also be applied to
other unsaturated-zone transport problems involving gas diffusion, such as
radon migration and the deposition of compounds from the atmosphere to shallow
ground water. In a calibrative mode, R-UNSAT can be used to estimate rates of
mass transport, biodegradation and volatilization rates, or transport
properties of unsaturated-zone sediments. In a predictive mode, R-UNSAT can be
used to predict the distribution of a species as a function of time and space
and to estimate mass-loss or loading rates to ground water.
Use Constraints The computer model source code written in Fortran 77. It is assumed that users
have access to a Fortran compiler. Users who do not have access to a Fortran
compiler may request executable files by contacting Matthew A. Lahvis or
Arthur L. Baehr at (609-771-3900).
Baehr, A.L., 1987, Selective transport of hydrocarbons in the unsaturated zone due to aqueous and vapor phase partitioning: Water Resources Research, v. 23, p. 1926-1938.
Lahvis, M.A., and Baehr, A.L., 1996, Estimation of rates of aerobic hydrocarbon biodegradation by simulation of gas transport in the unsaturated zone: Water Resources Research, v. 32, p. 2231-2249.
____ 1997, Documentation of R-UNSAT, a computer model for the simulation of reactive, multispecies transport in the unsaturated zone: U. S. Geological Survey Open-File Report 97-630, 104 p.
Landmeyer, J.E., Chapelle, F.H.,and Bradley, P.M., 1996, Assessment of
intrinsic bioremediation of gasoline contamination in the shallow aquifer, Laurel Bay Exchange, Marine Corps Air Station, Beaufort, South Carolina: U.S. Geological Survey Water-Resources Investigations Report 96-4026, 50 p.
McAllister, P.M., and Chiang, C.Y., 1994, A practical approach to evaluating natural attenuation of contaminants in ground water: Ground Water Monitoring Review, v. 14, p. 161-173.
Squillace, P.J., Zogorski, J.S., Wilber, W.G., and Price, C.V., 1995, A
preliminary assessment of the occurrence and possible sources of MTBE in ground water of the United States, 1993-94: U.S. Geological Survey Open-File Report 95-456, 15 p.
Tremblay, D., Tulis, D., Kostecki, P., and Ewald, K., 1995, Innovation
skyrockets at 50,000 LUST sites: Soil and Groundwater Cleanup, December 1995, p. 6-13.
U.S. Environmental Protection Agency, 1991, OUST corrective action 45-day study team report: U.S. Environmental Protection Agency, Office of Underground Storage Tanks, Washington, D.C.
Creation and Review Dates