The Nuclear Waste Management Organization (NWMO) was established by Canada’s nuclear energy generators in 2002 as a requirement of the Federal Nuclear Fuel Waste Act. The NWMO’s mission is to develop and implement collaboratively with Canadians, a management approach for the long-term care of Canada’s used nuclear fuel that is socially acceptable, technically sound, environmentally responsible, and economically feasible.
The site selection process began in 2010 and 22 communities expressed interest in “Learning More” about the plan. As of January 2019, there are 5 communities remaining in the process, including three in crystalline rock in northern Ontario and two in sedimentary rock in southern Ontario.
Ignace/Wabigoon, in northern Ontario, was the first community to advance to borehole drilling. A 1000m vertical borehole was cored within the crystalline-rock Revell batholith and on-site testing was completed March 2018. A robust plan was in place to characterize the hydraulic response and fluid chemistry in the borehole including:a suite of groundwater and porewater chemistry analyses (including pore water methods for Diffusive Isotope Exchange and Out-Diffusion); Flowing Fluid Electrical Conductivity (FFEC) logging; hydraulic packer tests; and a Westbay multi-level monitoring system.
The FFEC logging results suggested that small amounts of groundwater were entering the borehole, but sampling attempts were not successful (purging criteria not met). Groundwater samples will only be able to be collected during long-term monitoring activities. Porewater from core samples will provide additional water chemistry information. Additional hydrogeological and geochemical tools are planned for future borehole to maximize the potential for groundwater samples and to characterize the flow system including: noble gas isotopes; long-term pressure monitoring, sampling in Westbay intervals; Borehole hydraulic testing, long-term monitoring and porewater chemistry results from boreholes will support an ensemble of groundwater flow simulations based upon numerical methods to define the geosphere in 3-D (DFN models using MoFrac).