Wednesday, July 29, 2015

Russia to open first repository for extremely hazardous radioactive waste

Seversk chemical combine
Russia’s first point for long terms storage of “special” radioactive waste is to be built at the site of the EI-2 uranium graphite reactor production in Northern Siberia’s closed nuclear city of Seversk by the end of December, Russian news sources reported.
The repository will rely on exclusively natural barriers between the environment and some of the most radioactively dangerous waste produced in the history of nuclear weapons production.
The storage site’s completion should, according to reports in Russian media, coincide with the decommissioning of the EI-2 reactor, which is slated before the end of 2015. The repository will hold waste from that and other weapons-grade plutonium manufacturing reactors at the Seversk site.
Russia’s 2011 law on Management of Radioactive Waste characterizes as “special” radioactive waste that is too risky or too expensive to move.
Siberian Chemical Comine Seversk
The Siberian Chemical Combine at Seversk’s  radiochemical plant. (Photo: Siberian Chemical Combine)
The project to store the special waste at Seversk was announced to RIA-Novostion Tuesday by Andrei Izmestyev of the Pilot and Demonstration Center for Decommissioning of Uranium-Graphite Reactors, a division of Russia’s state nuclear company Rosatom that was tasked with implementing a decommissioning concept for the country’s 13 shut-down uranium-graphite military plutonium production reactors.
The production reactors are located across Russia, with five at Ozersk, which hosts the Mayak Chemical Combine, three at Zheleznogorsk’s Mining & Chemical Combine and five at Seversk. As a whole, they produced 170 tons of weapon-grade plutonium between 1948 and 1994, according to the World Nuclear Association.
The EI-2 will the first of Seversk’s reactors to be decommissioned. The EI-2 is Russia’s first dual-purpose production uranium-graphite reactor, capable of supplying thermal heat for energy and weapons grade nuclear material the same time.
The remaining four reactors at Seversk should be decommissioned by 2030, Seversk’s director, Sergei Tochilin, told RIA Novosti in October.
The decommissioning concept developed by the Pilot and Demonstration Center provides for building multiple safety barriers and sealing off shut down reactors rather than dismantling them individually.
This approach is estimated to cost $ 67 million per reactor. The reactors produced some 170 tons of weapon-grade plutonium between 1948 and 1994, according to the World Nuclear Association.
Izmestyev told the news agency that, by law, waste produced by government armament and defense programs –such as the production reactors at Seversk – and waste which arises as a result of a nuclear accident is automatically characterized as “special.”
Siberian Chemical Combine 2
Centrifuges enrich uranium hexafluoride with uranium 235. (Photo: Atomsrib.ru)
He also said that the technologies that would be used to store the special waste were specifically developed for the purposes at Seversk, and are the first of their kind, RIA Novosti quoted him as saying.
“Thanks to the developed technology […] there’s a way for the first time in world practice to safely decommission a uranium-graphite nuclear reactor via in-situ storage” with the creation of repository for special radioactive waste, he said.
Alexei Shchukin, expert for nuclear programs with the Environmental Rights Center (ERC) Bellona has pointed out the dangers storing graphite associated with RMBK-style reactors, which, like the EI-2, use graphite moderators to control nuclear reactions
“Carbon-12, of which [the graphite cylinder of an RBMK] consists, is transformed during the operation of the reactor by the influence of neutrons into the isotope carbon-14,” Shchukin said. “The ingress [of carbon-14] into the environment is extremely dangerous – it’s a radioactive element with a half life of 5400 years, and which is capable of penetrating the molecules of DNA.”
He added that, “For complete neutralization of the substance, 10 such [half life periods] are required at minimum, so accordingly, no less than 10,000 years.”
Izmestyev said that additional safety barriers between the special waste produced by the EI-2 and the environment were created with exclusively natural materials. He did not specify, however, whether these barriers were built especially for graphite.
“Any technological material has its limited terms of usefulness, where the application of natural materials guarantees nuclear and radiological safety for tens of thousands of years,” he said.

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