Simulation of radionuclide dispersion model following routine releases to water body

Under normal operating conditions nuclear facilities have potential release of radioactive substances into water bodies called routine releases. Radionuclide transfer in the environment is very complex so that simplification is made with a mathematical model approach using the Surface Water Modeling Systems 10.1 software that resolves hydrodynamic differential equations with the finite element method. Pollutants dispersion is strongly influenced by advection and diffusion process, which for the river the process of advection becomes more dominant. The goal of this research is to model the distribution of¹³⁷Cs radionuclides in Cisalak River located around Serpong Nuclear Area.¹³⁷ Cs is the most dominant radionuclide contained in radioactive effluent discharges. In this research the simulation is divided into two stages, they are the simulation of the hydrodynamic model using the Resources Management Associates-2 (RMA-2) module to model the flow and continued using RMA-4 to model the distribution of pollutants. The concentration of¹³⁷ Cs at the discharges source are the highest, lowest, and average value in the last three years. The results of the research it is obtained an overview of the¹³⁷ Cs distribution model along Cisalak river flow whose concentration value is a function of distance and time, besides that the pollutant concentration is very influential to the characteristics of the river and also the flow discharge, both river and effluent flow discharge.