PNNL

Abstract

Solidification of low-activity wastes with cementitious materials is a widely accepted technique that has the advantages of readily accessible materials, low cost, high physical strength, and easy tailoring for various waste streams. Concrete encasement contains and isolates the waste from the hydrologic environment. However, any failure of concrete encasement may result in water intrusion and consequent mobilization of radionuclides from the waste packages via mass flow and/or diffusion into the surrounding subsurface environment. A better understanding of the interactions of long-lived radionuclides in cemented matrices will ultimately lead to improved predictions of the long-term fate of these sequestered contaminants from cementitious waste forms.