This report presents new calculations of the motion of a redox front in a system of bentonite and fractured rock, incorporation advection and diffusion of oxidants in fracture water. The results reported here have been incorporated into preliminary base case calculations using the source term model CALIBRE. The model presented here differs mainly in its treatment of the effects of the fracture. Previously, a `zero-concentration` boundary condition was applied, and this resulted in retardation of the front near the fracture. When a more detailed advection-diffusion model is applied, the front is advanced in a neighbourhood of the fracture. (25 refs.) (au).