The challenges of nuclear waste management from a life cycle perspective

As nuclear industry grows and expands, the yearly amount of waste produced increases and it adds to the large quantity of nuclear wastes generated, and not yet disposed, in the last 50 years from existing plants. Consequently, the development of an international agreed policy to manage nuclear wastes is key to support such growth. Many countries, such as USA, Sweden, Canada, have opted for a direct disposal of Spent Nuclear Fuel (SNF) (Open Cycle); whilst others, such as the UK, Japan and France, have preferred reprocessing SNF (Closed Cycle). Other countries are yet to take a final decision (e.g. Spain, Argentina) and wait for future development in nuclear R&D. Economically an open cycle is much more advantageous than a closed cycle, but what about the environmental concerns? Life Cycle Assessment (LCA) approach may come to help to the Nuclear Industry as a means of evaluating and comparing alternative strategies on the basis of their environmental performances. Therefore, LCA studies carried in the nuclear field may be used to support the decision-making process when choosing between different Nuclear Fuel Cycles or Nuclear Waste Management strategies. Furthermore, the results of such LCA studies might serve to improve public attitudes towards the Nuclear Energy, provided that they are used in an open and transparent way. Up to the present very few LCA studies have been carried out in the nuclear context: the main cause for this shortage is the lack of a standard and consistent approach for the inclusion of ionising radiation within the Life Cycle Impact Assessment (LCIA) step. In that regard, not one reported LCA study has considered the impacts of radionuclide releases from operation of nuclear reactors nor from management of nuclear waste. The present study addresses this issue by proposing a novel approach for the assessment of the impact of radionuclide releases both as direct discharges (i.e. liquid and aerial) and from management of solid wastes in a Geological Disposal Facility. The approach is based on a risk methodology which relies on two generic models, publicly available, developed by the IAEA (International Atomic Energy Agency) and the NDA (Nuclear Decommissioning Authority). The proposed methodology will then be applied to the UK Nuclear Waste Management process for a complete LCA study where, along with ionising radiation impact, several other environmental impact factors will be evaluated. Real data, collated on field from UK nuclear facilities, will be used for the foreground system. The management of the amount of AGR/LWR fuel assemblies used to produce 1 TJ of electricity has been chosen as functional unit. Results of the study will show the overall environmental footprint of the UK reprocessing step of spent nuclear fuel both in terms of radiological and non-radiological impacts. Preliminary results will be presented at the conference