Description
The migration of species present in the geosphere that are generally considered to be gases; that is, species that would, if on their own, exist as free gases under the ranges of temperature and pressure found in the region of the geosphere of interest. Typical such gases include nitrogen, oxygen, hydrogen, methane, carbon dioxide, and the noble gases. In the geosphere, these gases may be present in a gaseous phase or dissolved in groundwater
SKB Number
SKB FEP Number
Ge04
Main Category
Main category for FEP
Internal process
System Component
System component to which the FEP applies
Geosphere
Handling
Explanation of how the FEP is treated
Excavation/operation: Neglected based on arguments supporting the assumption of small effects of unsaturated regions on inflows to tunnels.
Temperate: Included in a simplified manner in the backfill resaturation calculations.
Neglected for other calculations based on the assumption that gas generated in the repository can rapidly escape through the geosphere without causing a pressure build-up.
Periglacial: Neglected in SR-Site based on considerations that gas that may be trapped below permafrost will have a similar effect on groundwater flow to a slightly thicker permafrost layer. Also, gas may escape through taliks if present.
Glacial: Neglected in SR-Site based on the assumption that gas generated in the repository can rapidly escape through the geosphere without causing a pressure build-up (if permafrost is not present).
Earthquakes: Not relevant.
References
Bibliographic references to obtain more information
SR-Site Geosphere process report, TR-10-48, Section(s) 1.6, 3.2; SR-Site Main report, TR-11-01, Section(s) 7.4.5