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North American construction is back—smaller and faster—at OPG’s Darlington
“The nuclear renaissance is real here,” said Ontario Power Generation’s Subo Sinnathamby on May 8, one year to the day after OPG secured a final investment decision to build the first of four planned BWRX-300 reactors at its Darlington nuclear power plant, and shortly after the new reactor’s foundation was lifted into place. “We got our license to construct in April and our [final investment decision] in May, and we’ve been off to the races since.”
J. P. Schapira, R. K. Singhal
Nuclear Technology | Volume 128 | Number 1 | October 1999 | Pages 25-34
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT99-A3011
Articles are hosted by Taylor and Francis Online.
Among the natural thorium resources, monazite and the residues of rare-earth extraction will very likely be exploited first in case of a significant use of thorium-based nuclear fuels. The different waste streams have been identified from the present industrial practices used in the production of nuclear grade thorium from monazite extracted from beach sands. The radionuclides of utmost importance in various waste streams are 232Th, 228Ra, and 220Rn from the thorium series and 238U, 230Th, 226Ra, and 222Rn from the uranium series. There are three important steps, where the major radioactivity is generated. It is found that the total amount of solid wastes generated for the production of 1 t of thorium metal is ~10 t, which is ~50 times less than in the case of 1 t of uranium production. Among them, long-lived wastes represent a small volume and could be disposed of in a deep geological repository, as for alpha-active reprocessing wastes. The raw materials at the mining site are lower by one to two orders of magnitude in the general case of high-grade thorium ore in comparison to the present commercially exploited uranium ore. The short- and long-term impact of these wastes on the environment and radiotoxicity has been calculated. It has been found that the short- and long-term impact for the public is about two orders of magnitude lower than for the equivalent front-end uranium cycles. On the contrary, inhalation and ingestion dose commitments for an adult are about five and two times higher, respectively, in the case of pure thorium as compared to the equivalent uranium case.