Abstract:Three Dimensional Multiphase Fluid Flow Model Calibration Based on Ground Penetrating Radar

ROWLEY, T. H., Colorado School of Mines, Dept. Of Geology and Geological Engineering, Golden, CO

Groundwater contamination by organic solvents is a worldwide problem. The unique physical and chemical properties of dense non-aqueous phase liquids (DNAPLs) pose extraordinary problems to the currently used ground water monitoring programs and remediation plans. Organic solvents such as perchlorethylene ("perc") are considered highly toxic by the USEPA.

The project objective is to develop and refine methods of combining geophysical, geologic and hydrogeologic techniques and understanding to ground water contaminant research. This project is unique in its collaboration of ground penetrating radar (GPR), hydrogeologic data and computer modeling. Properties such as porosity and saturation of the DNAPL will be derived from nineteen GPR surveys. These surveys were taken during the Borden controlled DNAPL spill experiment conducted in Canada over 340 hours. Using a recently developed, full-waveform GPR forward modeling program, a 3D model of porosity, water saturation, and hydraulic conductivity will be assembled. The derived data will be introduced into an experimental hydrogeologic multi-phase fluid-flow computer model. Calibration of the compute model will be assisted by a newly developed inversion code. Previously, high density geophysical data sets could not be easily introduced into fluid-flow computer models due to the lack of inexpensive computers with the appropriate memory requirements.

The fluid flow model information can also be compared with twelve cores taken before and after the controlled spill experiment. This information will add to the knowledge of small scale DNAPL migration behavior not previously possible using noninvasive methods.

AAPG Search and Discovery Article #90931©1998 AAPG Foundation Grants-in-Aid