Determination of the clearance level of cemented evaporation concentrates radioactive waste and safety review disposal

Unsealed radioactive substances, radioactive waste, or contaminated/activated materials can be released from the control of the Nuclear Energy Regulation Agency (BAPETEN) through a clearance mechanism. One of the processed liquid radioactive waste products at the Radioactive Waste Management Installation, Directorate of Nuclear Facilities Management, National Research, and Innovation Agency (IPLR-DPFK BRIN) that may be proposed for clearance approval is 14 units of 950 L concrete shell evaporated concentrate cement. The concrete shell contains evaporated concentrate cement, cemented in 1989-2002. This study aims to obtain evaluation results of radioactivity characteristics, including radiation exposure rate, level of urface contamination, radionuclide content, and radionuclide activity concentrations contained in the concrete aggregate resulting from cemented evaporation concentrate, which is thought to have reached the clearance level, as well as obtaining a formulation of a clearance disposal strategy for the concrete shell 950 L and its safety overview. The object of this research was 14 units of 950 L cylinder shells with a diameter of 140 cm and a height of 130 cm. Based on the initial identification results and calculations, it had eached a clearance level. The measurements of the radiation dose rate, surface contamination level, and activity concentrations of α, β, and ϒ emitting radionuclides to ensure that the shell has reached the clearance level. The results showed that the highest dose rate was 0.15 µSv/hour, the highest surface contamination level was 0.0148 Bq/cm² for α emitting radionuclides and 0.0935 Bq/cm² for β emitting radionuclides. The radioactivity learance level tested ranged from 0.47020 - 0.66730. Based on the Regulation of the Head of BAPETEN No. 16/2012 concerning the Clearance Level, the radionuclide content in the 950 L concrete shells tested has reached the clearance level. The disposal of 14 concrete shell units through an unconditional clearance mechanism because the radiation dose that a critical group will receive is less than 10 µSv per year, and the shells do not contain hazardous and toxic materials. They will be disposed of through a clearance mechanism which can be used as a support structure for landslides caused by rainwater on sloping ground in the Serpong Nuclear Area. (author)