Safety assessment of near surface disposal for radioactive waste in Serpong nuclear area using PRESTO software

Abstract

The planning of the construction and operation of Near Surface Disposal (NSD) facilities for Radioactive Waste at Serpong Nuclear Area needs a safety assessment in order to provide assurance that the radioactive waste disposal system functions properly. The purpose of the safety assessment is to provide a reasonable scientific assurance that the disposal system will provide an adequate level of safety and meet the requirements to protect human health and the environment. The NSD facility is vault type with a size of 20.2 × 20.2 m with a depth of 2.6 m from the ground surface (4.43 m above the highest ground water level). The facility was designed to accommodate waste packaged in 200 l drums and 950 l concrete shells. The total capacity of the disposal will be 1350 drums and 144 concrete shells. The waste that was considered in the study contain radionuclides which are dominantly contained in the low level packaged waste and, as reference for the safety assessment, with short half-lifes (less than or equal to about 30 years), namely Co-60 and Cs-137. This study used the PRESTO software version 4.2 to calculate the migration/exposure of radionuclides from the facility into the environment as well as individual doses. The results indicate that the predicted individual doses of the population around the facility at the Serpong site still fulfill the dose limit value of the public based on BAPETEN Chairman Regulation No. 4/2013 on the Protection and Radiation Safety in the Utilization of Nuclear Energy.