HR: 15:00h
AN: IA33A-05    [Abstracts]
TI: Geoscientific Characterization of the Bruce Site, Tiverton, Ontario
AU: * Raven, K
EM: kraven@intera.ca
AF: Intera Engineering Ltd., Suite 200, 1 Raymond St., Ottawa, ON K1R 1A2, Canada
AU: Jackson, R
EM: rjackson@intera.ca
AF: Intera Engineering Ltd., Suite 200, 1 Raymond St., Ottawa, ON K1R 1A2, Canada
AU: Avis, J
EM: javis@intera.ca
AF: Intera Engineering Ltd., Suite 200, 1 Raymond St., Ottawa, ON K1R 1A2, Canada
AU: Clark, I
EM: idclark@uottawa.ca
AF: University of Ottawa, 140 Louis Pasteur, Ottawa, ON K1N 6N5, Canada
AU: Jensen, M
EM: mjensen@nwmo.ca
AF: Nuclear Waste Management Organization, 22 St. Clair Ave. East, 6th Floor, Toronto, ON M4T 2S3, Canada
AB: Ontario Power Generation is proposing a Deep Geologic Repository (DGR) for the long-term management of its Low and Intermediate Level Radioactive Waste (L&ILW) within a Paleozoic-age sedimentary sequence beneath the Bruce site near Tiverton, Ontario, Canada. The concept envisions that the DGR would be excavated at a depth of approximately 680 m within the Ordovician Cobourg Formation, a massive, dense, low- permeability, argillaceous limestone. Characterization of the Bruce site for waste disposal is being conducted in accordance with a four year multi-phase Geoscientific Site Characterization Plan (GSCP). The GSCP, initially developed in 2006 and later revised in 2008 to account for acquired site knowledge based on successful completion of Phase I investigations, describes the tools and methods selected for geological, hydrogeological and geomechanical site characterization. The GSCP was developed, in part, on an assessment of geoscience data needs and collection methods, review of the results of detailed geoscientific studies completed in the same bedrock formations found off the Bruce site, and recent international experience in geoscientific characterization of similar sedimentary rocks for long-term radioactive waste management purposes. Field and laboratory work related to Phase 1 and Phase 2A are nearing completion and have focused on the drilling, testing and monitoring of four continuously cored vertical boreholes through Devonian, Silurian, Ordovician and Cambrian bedrock to depths of about 860 mBGS. Work in 2009 will focus on drilling and testing of inclined boreholes to assess presence of vertical structure. The available geological, hydrogeological and hydrogeochemical data indicate the presence of remarkably uniform and predictable geology, physical hydrogeologic and geochemical properties over well separation distances exceeding 1 km. The current data set including 2-D seismic reflection surveys, field and lab hydraulic testing, lab petrophysical and diffusion testing, lab porewater and field groundwater characterization, and field head monitoring confirm the anticipated favourable characteristics of the Bruce site for long-term waste management. These favourable characteristics include a tight geomechanically stable host formation that is overlain and underlain by thick, massive, very low permeability shale and argillaceous limestone formations where radionuclide transport appears to be very limited and dominated by diffusion.
DE: 1835 Hydrogeophysics
DE: 3675 Sedimentary petrology
DE: 5114 Permeability and porosity
DE: 8099 General or miscellaneous
SC: International Association of Hydrogeologists, Canadian National Chapter [IA]
MN: 2009 Joint Assembly