Bentonite in nuclear waste disposal: A review of research in support of the Basalt Waste Isolation Project

The Basalt Waste Isolation Project is investigating the feasibility and safety of a high-level nuclear waste repository in the Columbus River basalts. A mixture of crushed basalt and sodium bentonite is under investigation as packing material around individual waste containers. A 75:25 basalt/bentonite mixture, with a density of 2. 1 g/cm**3, is the BWIP reference packing material. This paper discusses various tests performed on the materials, and reports on such material characteristics as hydraulic conductivity, swelling pressure, dehydration, corrosion of steel and copper, sorption, and others.