National strategy for research reactor spent fuel management: Argentina

Full text: The Radioactive Waste Management Strategic Plan approved by CNEA includes the strategy for RRSF management that is to be periodically reviewed in order to have the opportunity to consider or adopt new concepts and processes. Current planning considers that the operational wet storage will be followed by interim wet storage in a 16 m deep pool at LAPEP at the Centro Atomico Ezeiza, currently under construction. As regards the spent fuel currently stored at the facility with underground tubes, they will be sent to the storage pool at LAPEP. The new pool is designed to store spent fuel from all operating research reactors in Argentina: RA-1 (40 kW), RA-3 (10 MW) and RA-6 (500 kW). Nevertheless, the RA-6 HEU fuel inventory will be shipped back to the USA within the framework of the USDOE Foreign Research Reactor Spent Fuel Acceptance Programme. It is also expected that irradiated HEU fuel assemblies and fuel elements from the RA-2 critical assembly will be shipped back to the USA. Currently, experimental studies of conditioning are being performed involving diverse technologies. After evaluation of the different conditioning processes, with and without decladding, one conditioning route will be chosen for testing in hot cells with radioactive samples. Furthermore, in order to reduce amounts of LILW-LL - avoiding the need for isotopic dilution - a spent fuel processing option that includes separation of uranium is under consideration. For the RRSF processing options that are being studied, the selected conditioning technology will be implemented up to hot pilot scale for an output of 2-3 MTR SF/week. Such a pilot plant could start operation in 2015 according to present planning. Currently, aluminium based spent fuels from research reactors are in operational and interim wet storage. However, for an eventual extended storage as well as for disposal, there are some concerns about the suitability of the aluminium as a matrix resistant to water corrosion. Therefore, the preferred alternatives are extended storage in dry conditions and disposal of the derivatives from spent fuel processing instead of its direct disposal. Current planning for the development of a deep geological repository includes the construction and operation of an underground research laboratory starting in 2030 and the operational start-up of the deep geological repository by 2050.(author)