Examining Closure-Related Issues in Finnish Radioactive Waste Programs

The final phases of radioactive waste repository programs are the closure and post-closure phases. It may take several decades or up to a century or more (in the case of a deep geologic disposal facility for spent nuclear fuel) to reach the closure phases after operations begin. The post-closure phases can continue on for far greater periods of time.
The radioactive waste management obligation of an operator responsible for radioactive waste disposal ends when it is confirmed that the final disposal has been implemented safely and in the planned and approved manner. When the operator’s obligation has ended, the post-closure period for the repository begins and the responsibility for the radioactive waste is transferred to the Finnish State. Geologic repositories will not be directly observable after closure.
Presently in Finland, two low and intermediate-level waste radioactive waste repositories are in operation at depths of ~100 m and a high-level waste repository at a depth over 400 m for spent nuclear fuel is under construction with an operational license just submitted. In an effort to begin assessing the situation of Finnish radioactive waste repositories with respect to closure and post-closure, applicable Finnish legislative and regulatory requirements were reviewed. Additionally, relevant international guidance was considered as well. Overall, twenty-five closure-related requirements were identified. These requirements were divided into a set of nine categories including 1) closure performance, 2) closure planning, 3) closure implementation, 4) postclosure planning, 5) post-closure-actions, 6) post-closure resourcing, 7) post-closure responsibilities, 8) records preservation and 9) stakeholder engagement. The current handling of each identified closure-related obligation was explored and, in total, fourteen gap areas were found falling into four main domains: post-closure monitoring, knowledge preservation, transfer of ownership and post-closure responsibilities and stakeholder engagement.
In an effort to begin addressing these gaps/needs a set of actions are proposed. These actions are not described in terms of overall prioritisation. However, it is discussed, particularly in the case of post-closure monitoring, that strategic decisions should be made as early as possible.