Arbeitsbericht NAB 09-14

Reference pore water for the Opalinus Clay and 'Brown Dogger' for the provisional safety-analysis in the framework of the sectoral plan – interim results (SGT-ZE)

A single composition for a reference pore water for both the Opalinus Clay and "Brown Dogger" is proposed for all siting regions (Table 6-2). This reference pore water is very similar to that developed by Nagra (2002) for Benken. The uncertainty range (for Opalinus Clay) in the constraining P(CO2) is significantly reduced compared to 2002, resulting in a much reduced range in pH and alkalinity
(Table 6-4).

To account for the possibility that salinities as high as encountered at Mont Russelin (chlorinity of slightly more than modern sea water, 22 g/L), a high-salinity variant is also defined (Table 6-3).