RESRAD PARAMETER SENSITIVITY SIMULATION TO ASCERTAIN LOCAL PARAMETERS FOR SAFETY ASSESSMENT ON BANGKA ISLAND

Abstract

Tin slag and waste generated by tin processing often contain Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM), which pose significant radiation hazards to workers, the public, and the natural ecosystem. To mitigate these risks, the development of a dedicated landfill facility is crucial for managing the radiological impact. This study analyzes the implications of storing TENORM waste, both prior to and following the construction of a landfill. The challenge of TENORM management persists, primarily due to the presence of long-lived radionuclides include uranium-238 (U-238), thorium-232 (Th-232), and potassium-40 (K-40), which are often inadequately handled by industry. To address this, a landfill design was proposed and evaluated by software simulation using RESRAD-Offsite 4.0 software. The default parameter values are multiplied by 0.25, 0.5, 1, 1.5, and 1.75. The resulting dose calculations are compared to those using the default value. If the difference is below 10%, it is considered low sensitivity, between 10% and 1000%, medium sensitivity, and above 1000%, high sensitivity. The reserch aim to optimize safety and resource allocation,. From 194 parameters were simulated, with approximately half exerting a significant influence on dose estimations. This study used software simulations to determine the level of influence each parameter has on dose calculations.  Parameters who have low sensitivity are soil to plant transfer factor for Th and U, radionuclide spesific release for Th, U, and K, medium sensitivity are precipitation, total porosity saturated zones, high sensitivity are Fraction of time spent on primary contamination at indoor and fraction of time spent for livestock.