Abstract CTS-9809516 G. F. Pinder, U. of Vermont This is a collaborative project between research groups at the University of Vermont (Prof. G. F. Pinder) and the Autonomous University of Mexico (Prof. I. Herrera) in the area of multiphase flow simulation in porous media. Transport of non-aqueous phase fluids will be simulated using finite element method and collocation method with a new interpolation approach based upon splines under tension. The resulting set of algebraic equations will be solved using the conjugate gradient method based upon the optimal location of the collocation points. The method will allow for simulations of flows with sharp fronts and use of parallel processing algorithms. The collaborative project will include the professors and their students. This project was awarded as part of the NSF-CONACyT initiative. The collaboration will contribute to the development of long-term US-Mexico research collaboration in the area of computer simulation and environment (underground contaminant transport).