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Canada begins regulatory approval process for spent fuel repository
Canada has formally initiated the regulatory process of licensing its proposed deep geological repository for spent nuclear fuel, with the country’s Nuclear Waste Management Organization (NWMO) announcing that it has submitted an initial project description to the Canadian government.
According to the NWMO, the initial project description is a foundational document, detailing the repository’s purpose, need, and expected benefits and explaining how the project will be implemented. It also provides a preliminary assessment of potential impacts and describes measures to avoid or mitigate them. The NWMO is the not-for-profit organization responsible for managing Canada’s nuclear waste.
R. C. Lloyd, R. A. Libby, E. D. Clayton
Nuclear Science and Engineering | Volume 82 | Number 3 | December 1982 | Pages 325-331
Technical Paper | doi.org/10.13182/NSE82-A19393
Articles are hosted by Taylor and Francis Online.
Experiments were performed with a 122-cm-diam sphere to determine criticality of aqueous solutions of plutonium in a system having low-neutron leakage. The plutonium in the chemical form of Pu(NO3)4 had a 240Pu content of 2.52 wt%. The critical-sphere concentration obtained in this experiment was analyzed along with data from eight additional critical experiments to evaluate the minimum critical concentration for plutonium. The limiting critical concentration was determined to be 7.62 g Pu/ℓ, for Pu(NO3)4 without excess acid and 7.59 g Pu/ℓ for a 239Pu-water mixture. From these data, the Maxwellian-averaged thermal value of the number of fission neutrons emitted per neutron absorbed by 239Pu, eta, was determined to be 2.056 ± 0.037. The value at 2200 m/s is 2.100 ±0.041.
