Description

The movement of molecules or particles (containing radionuclides) both parallel and transverse to the direction of advection in response to Brownian forces. Also transverse movement of radionuclides that are advected along fractures or connected void spaces into stagnant porewater in the adjacent matrix - termed matrix diffusion.

Category

Category of FEP

Supercontainer EBS

Sub-category

Sub-category of FEP

Hydraulic processes

Ondraf Niras FEP Number

Ondraf Niras FEP Number

38

FEP Effects

Description of FEP Effects

Diffusion occurs in the presence of chemical and thermal gradients, and may affect the transport and spread of dissolved radionuclides.

NEA TN2 IFEP Reference(s)

Related IFEPs from the NEA TN2 List of Proposed IFEP Revisions [NEA/RWM/R(2013)8]

2.4.1.3 Diffusion (waste form). 2.5.2.3 Molecular diffusion (waste package). 3.3.2.3 Molecular diffusion (GDF).