A candidate concept for a Lithuanian repository for low-level radioactive waste (LLW) implies location above the groundwater level and placement of the waste in concrete vaults surrounded by smectitic clay of appreciable thickness as all-around embedment for retarding wetting and minimizing exposure of the waste packages to oxygen. For rational and cost-saving reasons the clay material is not processed, only stockpiled for desiccation to a suitable water content before placement and compaction. The clay is laterally confined by sandy fill and covered by erosion-resisting soil. The vaults rest on stable, elevated ground for minimizing subsidence and maintaining dry conditions. The time for water saturation of the clay is more than the required 300-500 years of isolation of the waste, which keeps the waste packages dry in this period. The paper describes the principles of design of the repository and its predicted performance of which creep strain of the clay is of particular importance.