News Watch 115 (Nov./Dec. 2006) Nuke Info Tokyo No. 115
Turbine damage due to “high-cycle fatigue”
On October 27th, Chubu Electric and Hokuriku Electric power companies submitted final reports to the Nuclear and Industrial Safety Agency about the causes of and response measures for damage to low-pressure turbines in their Hamaoka-5 (ABWR, 1380 MW) and Shika-2 (ABWR, 1358 MW) reactors (see NIT 113). Chubu Electric’s English press release states, “The combined stresses generated repeatedly by random and flashback vibration resulted in high-cycle fatigue and the occurrence of cracking.” Random vibration occurs as a result of “turbulence in steam flows within the turbines during no load and low load operations” and flashback vibration arises due to “high-speed reverse flows of steam in the turbine from water supply heater during load cutoff testing”.Both companies blamed the turbine maker (Hitachi) for taking insufficient care in the design of the vanes for the scaled-up low-pressure turbine used in these ABWR reactors. In a press conference held on the same day, Hitachi responded that the problem could not have been foreseen on the basis of engineering knowledge at the time. These different perspectives reflect the companies’ respective positions in relation to compensation for loss of income. No details regarding compensation have emerged so far.
Shifting international alliances in nuclear industry
On October 17th Toshiba announced that it had completed its purchase of Westinghouse. Originally Toshiba hoped to provide only 51-53% of the total price of $5.4 billion. However, one of the prospective partners, Marubeni, got cold feet and Toshiba was left to foot 77% of the bill. The other partners in the deal are the Shaw Group with 20% and Ishikawajima-Harima Heavy Industries with 3%.Hitherto Westinghouse has cooperated closely with Mitsubishi Heavy Industries (MHI) and Westinghouse President Steve Tritch says that he hopes to continue the relationship. However, on October 19th MHI announced that it had entered into a strategic partnership with Areva.
Not to be outdone, on November 13th, Hitachi and General Electric announced their intention to set up joint ventures in Japan and the US. The Japan-based company will be 80% Hitachi and 20% GE owned, while the US-based company will be 40% Hitachi and 60% GE owned. Final agreement on the alliance is planned for June 2007.
Mitsui feasibility study into development of Russian uranium
On October 6th, Mitsui & Co. Ltd. announced a joint feasibility study with Tenex into the development of a sector of the Yuzhnaya zone of the Elkon uranium ore field in Russia’s far eastern Republic of Sakha. The Yuzhnaya zone is believed to contain reserves in excess of 250,000 tons making it one of the largest uranium deposits in the world.
Aomori governor unimpressed by application for receipt of radioactive waste from abroad
On October 17th the Federation of Electric Power Companies applied to Aomori Prefecture and Rokkasho Village for permission to receive medium and low-level radioactive waste produced as a result of reprocessing Japanese spent fuel in France and the UK. The UK portion of this waste would be substituted with high-level waste of equivalent radioactivity content. The Mayor of Rokkasho, Kenji Furukawa, said, “consideration of the request will take time”, while Governor Shingo Mimura maintained that the first priority was to confirm the safety of the Rokkasho reprocessing plant. He took the view that the request was premature saying, “The circumstances are not right to consider this request now”.
Tsuno Town won’t apply for HLW dump
On October 30th the Tsuno Town Council (Kochi Prefecture, Shikoku Island) unanimously rejected petitions presented to it both for and against applying for consideration as a candidate site for a high-level waste dump. The council decided “not to become involved in this issue, either now or in the future”. In response to this decision Mayor Takeo Myojin said, “I have decided not to submit an application and consider the matter finished as of today.”
Application for pluthermal at Shimane-2
On October 23rd Chugoku Electric Power Company applied to the Minister for Economy Trade and Industry for a license variation to allow it to implement pluthermal at its Shimane-2 reactor (BWR, 820 MW). Earlier on the same day Takashi Yamashita, President of Chugoku Electric, visited Shimane Governor, Yoshinobu Sumita, and Matsue City Mayor, Masataka Matsuura, and received their permission to apply for the license variation. The safety agreement requires that the governor and the mayor give their permission for license variations. The prefecture had originally indicated that it would grant final permission before the application for a license variation was submitted to the minister, but in the end it decided to align itself with the more cautious approach of Matsue City. The approach finally adopted by both Shimane Prefecture and Matsue City involves a two-step process of first granting permission to apply for a license variation and then granting final permission after the minister’s approval is received.
Local approval for pluthermal at Ikata-3
On October 13th, Moriyuki Kato, Governor of Ehime Prefecture, and Kazuhiko Yamashita, Mayor of Ikata Town, handed letters of final approval for implementation of pluthermal at the Ikata-3 reactor (PWR, 890 MW) to Momoki Tokiwa, President of Shikoku Electric Power Company.
Call for Saga Prefecture citizens’ referendum re pluthermal
A petition was launched on October 3rd demanding that the question of whether or not to implement pluthermal at Kyushu Electric Power Company’s Genkai-3 reactor (PWR, 1180 MW) be decided by a Saga Prefecture citizens’ referendum. The legal requirement for such a petition is that at least one in fifty eligible voters (about 14,000 people) sign, but to make it more difficult for the prefectural assembly to reject the petition, the organizers are aiming to obtain the signatures of ten percent of eligible voters (70,000 people).Signatures can be collected until December 3rd. The validity of the signatures will then be checked and the petition for a referendum ordinance submitted to the governor. After receiving the petition, the governor will submit it, along with his own views on the matter, to the prefectural assembly.
A citizens’ referendum on pluthermal was held on 18 April 2001 in Kariwa Town, Niigata Prefecture (site of Tokyo Electric’s Kashiwazaki-Kariwa nuclear power plant). A majority of Kariwa residents opposed pluthermal in that referendum, but the proposed Saga referendum would be the first to address pluthermal at a prefectural level.
Request submitted for approval of new fuel plan for Monju
On October 13th, Japan Atomic Energy Agency applied to the Minister for Economy Trade and Industry for approval of its plan to replace some of the fuel at Monju(prototype FBR, 280 MW). Operation of Monju has been suspended since an accident relating to a sodium leak on 8 December 1995. Since then, the composition of the initial load has changed (as a result of the decay of plutonium-241 to americium-241) and the reactivity of the core has decreased. To overcome this problem, a portion of the fuel will be replaced by fuel with a one percent higher fissile component than that currently loaded.