Safety assessment of hypothetical near surface disposal at Serpong site: far-field modeling

The far field modeling of radionuclide disposed at Serpong site was carried out based on the hydrogeological data. The simulation of radionuclide in the groundwater was calculated by the PORFLOW computer code. The groundwater simulation was done for 2 cases. In the first case the conductivity of soil layer at Serpong site contains of two layers and in the second case just contains of one layer. The results of the first case, indicated that the flow calculations show that depending on the location of the disposal site, radionuclides that are released from the repository may either show up in the nearby Cisalak creek or in Cisadane river. The results of the second case indicated that the local flow system exist. This means that all radionuclides that migrate out of the repository will appear in the Cisalak creek. The transport time for radionuclides with a low retardation factor in lateric clay soil is around 10 years for a travel of 200 m distance