NAGRA Opalinus Clay (…002 - Version 1
FEP 10.2.10 Colloid production and effects​

Bentonite may be a source of colloidal particles to which radionuclides may become attached (sorption, incorporation). These colloids are likely to be immobile in the fine pore structure of the undisturbed Opalinus Clay (filtration), and may lead to clogging of Opalinus Clay pores. Colloids may be transported by diffusion and (if there is groundwater flow) advection in fractures in the EDZ or at the bentonite-HR interface.