Intera Engineering has been contracted by the Nuclear Waste Management Organization on behalf of Ontario Power Generation (OPG) to implement the Geoscientific Site Characterization Plan (GSCP) for the Bruce site located on Lake Huron, Ontario. The GSCP is described by Intera Engineering Ltd. (Intera, 2006; 2008a). The purpose of the site characterization work is to assess the suitability of the Bruce site to construct a Deep Geologic Repository (DGR) to store low-level and intermediate-level radioactive waste. This Technical Report (TR) presents the results of porewaters investigations conducted on formations sampled in boreholes DGR-3 and DGR-4. These results are integrated with porewater characterization work conducted on DGR-2 samples (Koroleva et al., 2009), building on the understanding obtained from this earlier research. The work described in this report was completed by the Rock-Water Interaction Group, University of Bern, Switzerland, under contract to Intera Engineering Ltd.