Experiments put a cork in radioactive waste
While geological isolation of radioactive waste is a common practice, assuring long-term safety in deep underground facilities isolating highly active radioactive waste is difficult. There is a need for standardised protocols and overall safety improvement in the use of plugs and seals in geological repositories. The EU-funded DOPAS (Full scale demonstration of plugs and seals) initiative has addressed the issue by running five full-scale plug and seal experiments in different storage facilities around Europe. The researchers anticipated that the knowledge gathered from these experiments will improve standard practice in the industry. Before commencing with the experiments, DOPAS spent some time defining the concept and design of each experiment. The researchers compiled reports on waste management organisations with experience in defining and creating the reference designs needed for the project. Starting with design basis processes, DOPAS studied the requirements for the structures of seals and how this knowledge can be applied to other repository elements. The researchers studied and gained more knowledge on the conceptual designs for plugs and seals and how they relate to safety. In the siting and excavation of plug and seal locations, DOPAS worked out how these locations are selected. The researchers then developed methods to excavate plug and seal locations and studied the operational safety issues that come with these excavations. When it comes to the installation of these plugs and seals, the researchers developed technology to facilitate the installations. With that, DOPAS gained knowledge on the operational safety and logistical issues that come with these installations. In an effort to learn more about monitoring plugs and seals, DOPAS also studied issues that are attached to monitoring these plugs and seals. After all the work, the researchers conducted full-scale testing to find out what knowledge was gained from DOPAS in working on the plugs and seals. DOPAS checked the technical readiness of the plugs and seals, and found the processes needed to get them ready for operation in the field. These results will form the foundation for the design, construction and implementation of better plug and seal technologies for radioactive waste repositories in Europe.
Keywords
Radioactive waste, plugs and seals, geological isolation, underground facilities, DOPAS
