Percolation flux encountering an opening such as a waste emplacement drift will tend to be diverted due to the influence of capillary forces. The diversion of seepage affects the flow field beneath a waste emplacement drift, resulting in reduced flow rates and water saturations. This zone of reduced flow rates and water saturations is called the drift shadow. Many of the potential waste emplacement drift are expected to divert all seepage. Seepage diversion and the resulting drift shadow will affect radionuclide transport from potential waste emplacement drifts. Radionuclide transport from the drift will occur by diffusion due to the lack of flow through the drift. The diffusive releases will primarily enter the rock matrix because nearly all of the water available for diffusive transport beneath the drift will be in the rock matrix. Exchange between the matrix and fractures in the drift shadow is restricted by the low fracture water saturations, thus radionuclides would initially transport towards the water table through the matrix. Transport through the matrix is much slower than transport in the fractures due to the much lower transport velocities in the matrix, leading to much longer transport times from the potential repository to the water table than in undisturbed fracture flow.