Repository location

Jacobs, G. K. Apted, M. J. "Eh-pH Conditions for Groundwater at the Hanford Site, Washington Implications for Radionuclide Solubility in a Nuclear Waste Repository Located in Basalt, Trans. Am. Geophys. Un.1981,62,1065. 

In a nuclear waste repository located in basalt, solution pH is controlled by interactions between groundwater and the reactive glassy portion of the Grande Ronde basalt (10). In situ measurements and experimental data for this system indicate that equilibrium or steady-state solutions are saturated with respect to silica at ambient temperatures and above. Silica saturation and the low, total-dissolved carbonate concentration indicate the pH may be controlled by the dissolution of the basalt glass (silica-rich) with subsequent buffering by the silicic acid buffer. At higher temperatures, carbonate, sulfate, and water dissociation reactions may contribute to control the final pH values. 

This paper focuses on a repository located in sparsely fractured rock with a hydraulic conducting horizontal fracture intersecting the vertical deposition hole (Figure lb). The analysis for the case of a homogenous intact rock (Figure la) is presented in Millard et al., (2003). This paper... 

Figure 2. Quarter symmetric model of the hypothetical repository located at 1000 meters depth (KTHs model).

This analysis aimed to evaluate the impact of THM couplings on the performance of a repository located in sparsely fractured rock. The results of this analysis can be summarised as follows ... 

Stock reference standards prepared in the laboratory from the dissolution of neat forms of the individual targeted chemical compounds or purchased from various suppliers. The EPA used to provide these from its repository located in Research Triangle Park, NC, but no longer does. 

With the proposed criterion applied when creating repositories for radioactive materials, the risk of death caused by the plutonium uptake by humans is actually excluded. This is due to the fact that areas are chosen for repositories located far enough from active flow exchange areas with low water inflows along the enhanced fracturing zones. 

The opening of the WIPP repository would reduce hinnan-health risks and increase the protection of humans and the environment by facilitating the removal of existing TRUW from surface-based and near-surface-based storage facilities and contaminated sites, several in proximity of population centers, to a TRUW repository located in a virtually uninhabited desert area at a depth of approximately 650 meters below the surface in the center of a stable and virtually impermeable rock salt formation. 

The second, and more important, consideration involves the possibility that in the future, when the institutional control ceases, the knowledge of the repository location might not be available to an individual or society seeking to develop natural resources. In this case, inadvertent intrusion into a repository could reduce its integrity, leading to release of radionuclides to the environment. 

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