Three-dimensional groundwater flow and advection diffusion code for treating decay chain of radioactive materials by finite element method

A code - PER8MIGR - based on finite element method, and incorporating an 8-node isoparametric elements has been developed for solving in three-dimensional treatment the groundwater flow and advection diffusion equations involving with the decay chain of radioactive substances. Galerkin's method is applied to discretize the permeability and advection diffusion equations, and linear matrix equations are solved by band matrix method. The Code is verified for applicability by agreement seen in benchmark tests for groundwater flow in which comparisons are made of the results obtained using the code with those of one- and three-dimensional analyses and with HYDROCOIN Level-1 Case-1 solution, and also in tests for nuclide, migration with the results obtained using other codes - AT123D, SWIFT, F.E.M. code of LBL and MIG3D in INTRACOIN test. The present work should permit accurate estimation of the flow and diffusion behavior to be expected of high- and low-level radioactive wastes in geological formations of complex geometry. (author)