Development of radioactivity transport model 'STRAG'

A computer code STRAG was developed for the analysis and the safety accessment of high level radioactive waste disposal. The STRAG predicts the release of radioactivity from waste glasses into the ground water. The code is composed of analysis models of; (1) temperature distribution in glass body, (2) thermal diffusion in radial direction, (3) leaching from surface to ground water. The Grambow model, developed in JSS project, is implemented in the leaching model. The chemistry in ground water is analysed by PHREEQE code, which is also implemented in the STRAG code. The comparisons of the experimental data and the code calculations show reasonable performance of the code. (author)