Accession Number : ADA306092

Title :   Improved Numerical Modeling of Groundwater Flow and Transport at the MADE-2 Site.

Descriptive Note : Final rept.,

Corporate Author : WEST VIRGINIA UNIV MORGANTOWN DEPT OF CIVIL ENGINEERING

Personal Author(s) : Gray, Donald D. ; Rucker, Dale F.

PDF Url : ADA306092

Report Date : FEB 1995

Pagination or Media Count : 25

Abstract : Public domain computer programs were used to attempt an improved model of the tritium plume observed during Macrodispersion Experiment 2 (MADE-2), a field scale natural gradient experiment conducted at Columbus Air Force Base, Mississippi. A computational grid having 66 rows, 21 columns, and 9 layers was used. The finite difference program MODFLOW was used to simulate the flow of groundwater through a 330 m x 105 m computational domain. Solutions for the 468 day experiment were obtained using a Sun Sparcstation 2 for several choices of convergence and storage parameters. The simulations had small mass balance errors and were consistent with continuous head observations. The smallest storage coefficients gave the best agreement. The flow model is about as accurate as the data permit. Tritium plume simulations used the mixed Lagrangian-Eulerian finite difference program MT3D to solve the contaminant transport equation using the MODFLOW-predicted flow field. Thirteen runs were made using various advection algorithms and dispersivities, but none was successful. Numerical instabilities or grossly unrealistic predictions ended every run by simulation day 141. Further work is needed to obtain a satisfactory plume prediction. (AN)

Descriptors :   *MATHEMATICAL MODELS, *GROUND WATER, COMPUTER PROGRAMS, DATA BASES, ALGORITHMS, COMPUTERIZED SIMULATION, WATER FLOW, CHEMICAL CONTAMINATION, PARAMETERS, GRIDS, FINITE DIFFERENCE THEORY, AQUIFERS, WATER POLLUTION, FLOW FIELDS, MATHEMATICAL PREDICTION, SOLVENTS, AIR FORCE FACILITIES, PLUMES, EULER EQUATIONS, JET ENGINE FUELS, ADVECTION, FUEL CONTAMINATION, CONCENTRATION(CHEMISTRY), WATER TABLE, LAGRANGIAN FUNCTIONS, TRITIUM, HYDRAULIC CONDUCTIVITY.

Subject Categories : Hydrology, Limnology and Potamology
      Water Pollution and Control

Distribution Statement : APPROVED FOR PUBLIC RELEASE