Fracture specific water sampling and electrical conductivity measurements at the Olkiluoto site in Eurajoki, drillholes OL-KR32, OL-KR41 and OL-KR46

Fracture-specific water sampling and electrical conductivity (EC) measurements were performed in drillholes OL-KR32, OL-KR41 and OL-KR46 at the Olkiluoto investigation site from May to October in 2013. The measurements were conducted using Posiva Flow Log, Difference flow method (PFL DIFF) with a configuration for water sampling. The purpose of the measurements was to get a fracture specific water samples for groundwater analysis. This report presents the principles of the method and the results of measurements and samplings. The main point in the investigation programme was water sampling. The incidental measurements were carried out for controlling the quality of the sampling. Flow and single point resistance (SPR) measurements were performed in order to locate the target fractures for sampling. During sampling at a target fracture the flow rate, electrical conductivity and temperature of the flowing water were also monitored. (orig.)