Contribution to fission product transport in the ground in connection with the underground arrangement of nuclear reactors; Explanation of planned experiments

Automatic translation: This work describes the fission product release path in the event of a hypothetical accident (loss of coolant and failure of container integrity) in an underground reactor plant, although no statement is made about the relevance of such an accident. By choosing suitable filling materials, the backfilling of the containment container can be optimized in terms of its fission product retention properties and thus prevent radioactive contamination of the environment. In addition to the description of the radioactive Source and the theoretical description of the spread of radioactive substances in the backfill and the subsequent natural soil, the proof of the safety containment of the entire Kr-85 activity of an HTR 1160 is based on a Loss of coolant accident with failure of containment integrity is calculated based on a simplified calculation model. An attempt is also being made to systematize the release paths from the source to the sink (humans) and to identify the transmission chain using transmission coefficients. Another part of the work describes the Experimental arrangement currently under construction to determine the diffusion and adsorption coefficients of the filling materials in question in order to have sufficient realistic input data for later calculations of the dispersion of fission products in the filling material and the soil.