Movement of Radionuclides in the clay
One of the advantageous properties of clay as a host rock, is that it will retain certain radionuclides for a very long time. At SCK CEN, many experiment have been and still are conducted by scientists on Boom Clay samples at lab scale, in which the transport of various radionuclides through the clay is investigated.
In HADES, a number of in situ experiments have been installed to demonstrate that the knowledge that was built, is also valid on a large scale in a representative environment. Some of these migration experiments have been running over decades, providing valuable input for the Belgian programme on radioactive waste management.
NIRAS/ONDRAF explains the migration of radionuclides through clay in laymans terms on their website (available in French and Dutch)