Sessions VI and VII Conclusions and summary Francois Besnus Session Chair Cape Town July 6, 2007

Session VI, Safety Demonstration The Use of Safety Cases Structure of safety case should be maintained through every stage of the step-by-step process, with the content of the safety case being progressively developed as the project proceeds. For each key step of decision making, a decision should be taken only if structured information on all important elements of the disposal system is available Whatever the stage is the Safety case must back up on a Safety assessment that always comprises three components: The assessment of the engineering, of the impact and of the management system

Session VI, Safety Demonstration Vaalputs PCRSA The presentation focused on the radiological impact, gave an overview of the knowledge necessary to establish a comprehensive set of scenarios and illustrated that the use of sensitivity analysis to adjust the safety strategy. The assessment concluded that the likelihood is high for post-closure safety at Vaalputs to be demonstrated successfully for the disposal of a national inventory of LILW

Session VI, Safety Demonstration Safety Assessment Conclusions The safety assessment is a step-by-step process, required to support the safety arguments in an integrated manner. It emphasizes the engineering suitability of a site, gives orders of magnitude of the possible radiological impacts and demonstrates that the necessary management system.

Session VI, Safety Demonstration International harmonization projects Presentation gave an overview of the projects conducted by IAEA that provide an important input for helping member states to set out efficient methods in appying safety standards On of the project,SAFRAN, dedicated to the development of a software for assessing a safety case was presented at the end of the session.

Session VI, Safety Demonstration Regulatory Romania The regulatory framework as applied in the country was presented. Authorization follows a phased approach which includes predisposal, disposal storage and decommissioning. The presentation outlined the different existing facilities in the country and their functions. Currently a disposal facility is situated at Baita Bihor, which was designed to handle low and intermediate waste. A new repository is planned at Saligny. A spent fuel facility will be provided at Cernavoda.

Session VI, Safety Demonstration Safe Management of Rad Waste in China The Chinese nuclear industry is well established and has regulatory processes for most activities regarding waste management in place. However they are still facing issues such as NORM, disused sealed sources, lack of understanding by the public and politicians

Session VII, Common Framework

The panel discussion touched on the issues of Pros and cons of prescriptive vs. a performance based approach. It was generally agreed that the performance based approach provides greater flexibility and a better opportunity to achieve an optimized solution. However, it was also pointed out that it requires a mature regulator and that it may not be suitable for all licensees. Small licensees would likely not have the resources for a propose-dispose approach. It was recognized that setting radiological criteria for the long term would be difficult. Various options were discussed and it was pointed out that the most robust solution may also end up being the least costly. Also, there may be safety benefits in carrying out the work right away. Since the common framework is also a common approach to safety, it is expected that its implementation would lead to better stakeholder acceptance. Again, countries could integrate the guidance in their own documents. While it is hard to quantify an acceptable a tradeoff between economy and safety, the most expensive option may turn out to be the cheapest.

Session VII, Common Framework It was felt that the existing proposal would accommodate mixed waste. The common framework links management options and classification. Implementation would require programmatic and management tools in addition to regulations. Equivalencies in the proposal for NORM may require some revision as they are not truly equivalent and the two classification schemes should agree on NORM definitions. Tailings pose unique problems due to their volume and long term hazard and other solutions may be required to deal with local conditions and effects. The participant touched on the subject of how safe is safe why propose near surface when sooner or later will need a DGR? (depends on situation) It was clarified that the proposal is an IAEA recommendation, which may be published as a separate document. There is no link to the Joint Convention.

Session VII, Common Framework Conclusions There are common safety, technical, economical and societal aspects that need to be addressed and these could be best handled through a common approach.. A common framework will help to find a safe and cost effective disposal solution for the various wastes and will assist in decision making to link a waste type with a suitable disposal option. The IAEA should issue the document on a common framework. Countries that have developed policies for the management and disposal of nuclear waster could use the document to provide background for their policies, while other countries could use the document for policy purposes.