Description
The initial degree of saturation of the EBS will be less than 100%. The ingress of host rock pore fluid, in time, will lead to resaturation of the EBS, albeit gas pressurisation could lead to subsequent desaturation.
Category
Category of FEP
Sub-category
Sub-category of FEP
Ondraf Niras FEP Number
Ondraf Niras FEP Number
FEP Effects
Description of FEP Effects
There is evidence that clogging of the concrete in the EBS occurs, limiting the saturation of the buffer and subsequent transport of aggressive species. This would affect the assumptions on the corrosion and chemical conditions in the EBS. The use of an envelope would further reduce the flux of host rock water towards the overpack. Clogging and the envelope will significantly delay the saturation of the buffer. In addition, gas pressurisation could lead to water displacement and desaturation of the EBS (see FEP 46).
Reference(s)
References Relevant to FEP
RD&D Plan , section 4.2.3.1
NEA TN2 IFEP Reference(s)
Related IFEPs from the NEA TN2 List of Proposed IFEP Revisions [NEA/RWM/R(2013)8]