Inventory estimation of ³⁶Cl and ⁴¹Ca in concrete of Kori Unit 1

The radionuclide inventory prediction of a nuclear power plant can help establish decommissioning plan by providing information of radiation environment. Accumulated radionuclides in reactors and related facilities after reactor shutdown can be divided into neutron activated materials and contaminated materials. Among the neutron activated radionuclides, ³⁶Cl and ⁴¹Ca are important from the viewpoint of disposal because of its long half-life and physiochemical characteristics. In this research, we calculated the radionuclides of ³⁶Cl and ⁴¹Ca in bioshielding concrete by estimating the neutron flux and cross section using the MCNPX. And we evaluated the inventories of ³⁶Cl and ⁴¹Ca using the activation calculation code ORIGEN2