In a co-operation project between Ringhals nuclear power plant and IVL, a combination of techniques for separation and removal of radioactive substances from water has been tested and evaluated. The goal of the project was to reduce the outlet of water bound radioactivity with at least a factor of 50-100, which was fulfilled during the project. The techniques chosen were dead end filtration (as pre-treatment) followed by gas transfer membranes (GEM), cross flow membrane filtration (OF/RO) and ion exchange using ion exchange resin or electrical deionisation (EDI). The feed water to the test rig was preferably letdown water from PAR-coolant, which contained low levels of activity together with a varying concentration of boron (0-2000ppm) and Lithium (0-3.5ppm). In addition, miscellaneous wastewater from sinks and floor drains was treated in the same system. The test plant was set up on site at the Ringhals 2 pressurised water reactor (PAR) and designed to have a capacity of treating a maximum of 2.5 m3/hour.