ASOURCE: Source Term Analysis Tool for Advanced Fuel Cycle

In 2007, the 3rd Comprehensive Nuclear Energy Promotion Plan, passed at the 254th meeting of the Atomic Energy Commission, was announced as an R and D action plan for the development of an advanced fuel cycle adopting a sodium-cooled fast reactor (SFR) in connection with a pyroprocess for a sustainable stable energy supply and a reduction in the amount of spent fuel (SF). It is expected that this fuel cycle can greatly reduce the SF inventory through a recycling process in which transuranics (TRU) and long-lived nuclides are burned in the SFR and cesium and strontium are disposed of after sufficient interim storage. For the success of the R and D plan, there are several issues related to the source term analysis. These are related with the following: (a) generation of inflow and outflow source terms of mixed SF in each process for the design of the pyroprocess facility, (b) source terms of mixed radwaste in a canister for the design of storage and disposal systems, (c) overall inventory estimation for TRU and long-lived nuclides for the design of the SFR, and (d) best estimate source terms for the practical design of the interim storage facility of SFs. A source term evaluation for a SF or radwaste with a single irradiation profile can be easily accomplished with the conventional computation tool. However, source term assessment for a batch of SFs or a mixture of radwastes generated from SFs with different irradiation profiles. A task that is essential to support the aforementioned activities is not possible with the conventional tool. Therefore, hybrid computing program for source term analysis to support the advanced fuel cycle was developed