Tests on a 2 tonne block of slate help to show how radioactive materials move through fractures.
It is expected that the repository will operate for at least 50 years. Rigorous Quality Assurance procedures will be applied to the packaging process and to the operations at the repository as the waste packages are placed in the caverns. When the repository stops receiving waste - sometime after the year 2060 - the people of that time will be able to decide on whether to seal finally the access tunnels and shafts. However, when planning for very strict safety standards, Nirex assumes that the repository will be sealed and that long-term safety will not depend on continuing human involvement. And the repository will only go into operation in the first place if Nirex can demonstrate to the satisfaction of independent regulators that the repository designed on this basis will meet stringent long-term safety requirements. Although the drums or boxes will corrode with time, the special cement poured around them will help to inhibit corrosion. So while the access ways are open it would be relatively easy to retrieve packages.
But what would happen in the extremely unlikely event that monitoring from the surface showed later that significant radioactivity could find its way to the surface? Then standard mining techniques could be used in retrieval of the waste. Although this would take time, the slow evolution of conditions underground could be expected to allow years to plan and complete retrieval.
Tests
on a 2 tonne block of slate help to show how radioactive materials move through
fractures.