Nuclear fuel cycle activities

During the time when economic sanctions were in force against South Africa, many nuclear fuel cycle activities were developed indigenously. Uranium production has generally been a by-product of gold or copper mining but, with the increased demand and prices today, further exploration is in progress. Originally, fuel for Koeberg was imported but, because of

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(a)

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(b)

20.14 ( a, b) Decontamination of historical conversion plant to re-use facility [1].

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20.15 Two PWRs situated at Koeberg [1].

sanctions, the Atomic Energy Corporation set up conversion, enrichment and fuel manufacturing services for Koeberg. Enrichment was done at Pelindaba. For research reactor and military use, 45% enriched uranium was produced and for Koeberg low enriched material. Operations were halted in 1990 and 1995, respectively.

The new South African nuclear policy advocates re-development of the country’s nuclear capabilities. It potentially allows for the country to imple­ment conversion and enrichment facilities in order to gain more benefit from its uranium reserves. The ambitious programme goes still further and spans the full nuclear fuel cycle, to include fuel fabrication, reprocessing and recycling. The explicit policy goal is ‘attainment of global leadership and self-sufficiency in the nuclear energy sector in the long term’ [17]. An inves­tigation commissioned by the Department of Minerals and Energy con­cluded that it would not be advisable to exclude the reprocessing, conditioning and recycling of used fuel. Both national and foreign reproc­essing options are conceivable and the government has requested that these options be investigated.

An integrated waste management strategy must take into account all of the radioactive wastes from all nuclear activities — in the past (legacy wastes), currently (mining, power production, medicine, industry and research) and in the future (decommissioning and, potentially, enrichment, fuel fabrication and reprocessing). This implies that, despite its present modest nuclear programme, South Africa must address a range of waste management issues as wide as that in the most developed nuclear countries of the world. New issues will arise if fuel cycle activities are expanded. For example, experience in the UK and other countries has shown that, if reprocessing is undertaken, then waste streams become significantly more diverse and new questions, such as whether surplus plutonium is a resource or a waste, must be addressed [18]. This emphasizes the need for a compre­hensive and integrated waste management strategy and operational pro­gramme. In the present report, however, attention is focused on the management of the wastes from power production and, in particular, on the SF and HLW.

Regardless of any HLW management strategy chosen in the future, a deep geological repository is needed, as long-term storage of SNF and HLW is not considered attractive but recognized as an interim option. Suitable high isolation environments are available in South Africa to host a deep geological repository. However, the development of a deep geological

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20.16 Concept for a HLW repository at Vaalputs (1990s).

repository is a multidisciplinary process, by nature involving legal, technical, safety, economic, but also societal requirements/constraints. For the selec­tion of a site for long-term management of SNF and HLW, public participa­tion will be included.

The following has been completed as part of the process to establish a deep geological disposal repository:

• The potential of the current Vaalputs site to be used as a deep geological disposal site was investigated by Necsa during the early 1990s. The initial schematic concept can be seen in Fig. 20.16.

• Eskom completed feasibility studies with regard to geological disposal site selection, repository design, R&D requirements, interim storage, encapsulation plant, SNF transportation in 2007.

• Eskom ‘Technical SF Management Plan’ based on direct disposal (for costing and planning purposes).

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