Experiments to determine the effect of canister corrosion products on the transport of radionuclides will be undertaken using the Fe(II1) oxides goethite and hematite as proxies for the expected corrosion envelope that will form as a result of alteration of the corrosion allowance overpack prior to the breaching of the waste container. Samples of ESF invert concrete that have been crushed, or left intact but fractured, and that have been subjected to hydrothermal alteration will be used to determine the effect of cementitious materials on transport of radionuclides. A mixture of CaC03, SiO,, and aggregate will be used as a proxy for completely carbonated concrete.