Abstract
Decommissioning is the final stage of the reactor lifetime. A preliminary decommissioning plan has been presented for the TRIGA Mark II Research Reactor which is owned by the Democratic Republic of Congo (TRICO II). The first step in the decommissioning plan is the safe handling of the spent nuclear fuel to its final destination. Monte Carlo MCNPX code was used for modeling the history of the spent fuel of the reactor. The activity and inventory of the radionuclides for the spent fuel of the reactor were calculated. These data are necessary to support the decision-makers and the radiation protection requirements.
The decommissioning strategy, management, organization, and decommissioning activities were presented based on the IAEA guidelines. The cost estimate of the decommissioning of the TRICO II reactor was calculated using IAEA software, CERREX code. The input inventories of the decommissioning activities were estimated.
The calculated total activity for the spent nuclear fuel is equal to 19.32 E+02 Ci. and the average value for each spent fuel element was about 27.603 Ci. Pu-239, Pu-241, and U-233 are fissile nuclides produced during TRICO II operation periods, their total amount is about 4.0 g of fissile nuclides.
Also, the results showed that the estimated decommissioning cost was about six million US dollars, which is in the range of cost estimation for similar TRIGA reactors. Moreover, the total amount of radioactive waste generated from the decommissioning activities has been estimated to be about, 806.5 tons of low-level waste, which can be managed.