The ‘Transports’ library includes modules for calculation of the atmospheric, groundwater or surface runoff transport of radionuclides from the contamination source to different receptors. The respective source term modules are described in the following table.
Module | Description |
---|---|
Aquifer, Aquifer mixing | These modules simulate radionuclide transport in the aquifer. The model employs 1D flow tube schematization of radionuclide transport process in the subsurface. The modeled radionuclide transport mechanisms include advection, dispersion and retardation due to sorption (Kd model). Radionuclide transfers due to advection and dispersion process in groundwater are modelled using the approach described in [IAEA, 2004, Annex C] |
Unsaturated zone | This module simulates 1D vertical radionuclide transport in the unsaturated zone. The modeled radionuclide transport mechanisms include advection, dispersion and retardation due to sorption (Kd model). Radionuclide transfers due to advection and dispersion process are modelled using the approach described in [IAEA, 2004, Annex C]. |
Surface Runoff | This module simulates radionuclide mobilization and transport in surface runoff from the soil of contaminated watershed. The model operates total radionuclide inventory in the so called “exchangeable soil layer”, which represents the upper soil layer interacting with surface runoff [Bulgakov et al., 1999]. Radionuclide concentrations in runoff water and adsorbed on suspended particles are calculated using the equilibrium Kd-based sorption models, while the soil erosion process is described using empirical coefficient. |
Atmosphere SR-19 | This module simulates atmospheric dispersion of contaminant from the point source using Gaussian plume atmospheric dispersion model described in [IAEA, 2001]. |
Atmosphere chronic | This module calculates atmospheric dispersion of contaminant from the chronic (steady state) source of atmospheric contamination to the receptor point. It employs normalized radionuclide concentrations in the atmospheric air and deposition rates for a unit release rate from the source (that shall be evaluated using an external model). These values are scaled with the actual release rate from the source. |