Description
The saturation of the bentonite creates a swelling pressure on the host rock and waste canister. The precompacted blocks beneath the canisters, which have a dry density of 1650 to 1750 kg m-3, will develop a swelling pressure in the order of 4 to 18 MPa. The granular bentonite filling the remaining region around the canisters will have a swelling pressure of ~2 to 4 MPa. Maintenance of a significant swelling pressure assures that bentonite has a low hydraulic conductivity.
OPA Category
Category as used in the OPA assessment
Bentonite buffer
OPA Number
Number as used in the OPA assessment
1.02
Waste Relevance
Classes of waste to which this FEP is relevant
SF/HLW
NEA V1 IFEP Reference(s)
Related IFEPs from the NEA V1 IFEP list from 1999
2.1.04, 2.1.07, 2.1.08