NAGRA Opalinus Clay (…002 - Version 1
FEP 14.3.3 Sorption / retardation

The advective transport of radionuclides along the pathways identified in 9./3.01 is retarded by chemical processes which include cation exchange and surface complexation on clay minerals, carbonates and other minerals and are collectively termed sorption processes. Advective transport along fractures would also be retarded by matrix diffusion.