An important part of the site investigations conducted by the Swedish Nuclear Fuel and Waste Management Company (SKB) is the characterisation of groundwater chemical conditions in the deep bedrock environment where a final repository for spent nuclear fuel is planned to be located. This work is currently in its final stages at the two candidate sites, Forsmark and Laxemar, and should be completed by the summer of 2007. It is essential that the information which is gathered is of high quality and representative of conditions in the environment of consideration.
Parameters of particular interest are those that are related to SKB´s suitability criteria such as Eh, pH and salinity, but a range of other geochemical parameters are also needed to establish a sufficient site understanding. The process of extracting the required information has been more problematic than expected during the early stages of the site investigations, and it is therefore of key interest to evaluate this part of the site investigation programme in more detail.