An experimental study on permeability of concrete silos for performance assessment of radioactive waste repositories

Groundwater flow dominates the transport of radionuclides from radioactive waste to biosphere for relatively short time in L/ILW repository compared to diffusion. The repository consists of natural and engineered barriers. The role of the engineered barrier is quite important for a shallow land repository. The concrete outerwall (silo) has to ensure low permeability against water flow besides the other requirements it has to meet as an engineered barrier. In this study, the permeability of a whole silo constructed by two improved methods is assessed. As the permeability is increased due to a defective zone, improved constructing methods result in a silo with less defective zones and a permeability rate 10{sup {minus}9} cm/s can be achieved.