NEW GUIDANCE FOR GEOLOGICAL DISPOSAL OF NUCLEAR WASTE IN SWEDEN

摘要

In its recently issued guidance on geological disposal of spent nuclear fuel and nuclear waste the Swedish Radiation Protection Authority (SSI) develops the concepts of the regulatory risk target, best available technique (BAT) and optimisation, and gives recommendations on how to demonstrate compliance with SSI's regulations for different time periods after closure of a geological repository. Because a post-closure risk analysis will always be associated with inescapable uncertainties, the application of BAT is seen as an important complementary requirement to risk calculations. The guidance states that the implementer should be able to motivate all important choices and decisions during the development of a repository, including siting, design, construction and operation, in relation to the repository's long-term protective capability. Although the risk target is in principle independent of time, i.e. the basic premise is that future generations should be given the same protection as today's generation, the guidance acknowledges the increasing difficulty of making meaningful assessments of risk in the distant future. This is reflected in a differentiated expectation in the reporting of compliance arguments: for long-time periods after closure (beyond 100 000 years) more emphasis is given on robust measures of repository performance than on calculated risks that are based on speculative assumptions on, e.g. future climate and human society.