NRC high-level radioactive waste research at CNWRA, Calendar year 1991. Volume 2

This is an annual status report on the results of research conducted on behalf of the US NRC by the Center for Nuclear Waste Regulatory Analyses in support of activities under the Nuclear Waste Policy Act, as Amended. Nine specific projects are underway; eight of which are reported here. The Geochemistry project is using laboratory methods and computer calculations to assess key geochemical constraints and to evaluate sorptive properties of zeolites present at the proposed repository site. The Thermohydrology project has as its focus improved understanding of heat and fluid flow in unsaturated media. Laboratory, field, and calculational studies are combined in the Seismic Rock Mechanics project to examine the effects of repeated seismic loadings on the rock-mechanical and hydrological responses of rock masses. The Integrated Waste Package Experiments have been initiated to evaluate degradation modes of candidate waste container alloys. Three-dimensional computer analysis techniques are being used to investigate spatial variability of flow and transport in variably saturated fractured porous media in the Stochastic Flow and Transport project. The recently initiated Geochemical Analogs project seeks to investigate the role of such analogs in the licensing process, and is currently focused on characterizing and evaluating a potential site for investigation.more » The Sorption Modeling Project has as its objective the evaluation and eventual selection of model(s) of sorption processes which are deemed technically acceptable in the context of repository licensing. Finally, the Performance Assessment project is directed toward developing and evaluating methodologies for evaluation of the long-term performance of the proposed repository.« less