Geologic Factors in Nuclear Waste Disposal

The study of geosciences and their relation to nuclear waste disposal and<br/>management entails analyzing the hydrology, chemistry, and geometry of the<br/>nuclear waste migration process. Hydrologic effects are determined by<br/>analyzing the porosity and permeability (natural and induced) of rock as well,<br/>as pressures and gradients, dispersion, and aquifer length of the system.<br/>Chemistry parameters include radionuclide retardation factors and waste<br/>dissolution rate. Geometric parameters (i.e., parameters with dimension)<br/>evaluated include repository layer thickness, fracture zone area, tunnel<br/>length, and aquifer length. The above parameters act as natural barriers or<br/>controls to nuclear waste migration, and are evaluated in three potential<br/>geologic media: salt, shale, and crystalline rock deposits. Parametric<br/>values are assigned that correspond to many existing situations. These<br/>values, in addition to other important inputs, are lumped as a hydrology input<br/>into a computer simulation program used to model and calculate nuclear waste<br/>migration from the repository to the biosphere, and potential individual and<br/>population dose and radiation effects. These results are preliminary and show<br/>trends only; they do not represent an actual risk analysis.