Yucca Mountain Near Field Environment Considerations for Engineered Barrier System Design and Performance

Wilder, Dale G.; ,

Yucca Mountain Near Field Environment Considerations for Engineered Barrier System Design and Performance

by Dale G. Wilder, Lawrence Livermore Natl Lab, Livermore, United States,

Document Type: Proceeding Paper

Part of: High Level Radioactive Waste Management 1991

Abstract:

Waste emplacement environment will be essentially dry for at least 300 years and will likely continue to be dry for more than 1000 years, both as a result of the unsaturated ambient conditions and as a result of thermally induced drying. As the heat generated by the waste dissipates, there will be a gradual return to ambient (65%) saturation. Dry conditions are favorable to the waste container and waste form performance since corrosion by liquid water is the most aggressive environment for the container and since leaching by liquid water is the most likely mechanism for release and transport of radionuclides from the EBS. Chemical changes may take place as a result of the drying process. These chemical changes may result in permanent changes in hydrologic properties. Specifically, porosity, hydraulic conductivity, and matric potential may be altered due to deposition of minerals within the pores as a result of drying. Also, fracture healing may result from mineral dissolution/deposition associated with heating/drying processes which would impact the potential for fracture flow.

Return to search