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The Paducah Gaseous Diffusion Plant is a facility located in McCracken County, Kentucky, near Paducah, Kentucky that produced enriched uranium 1952–2013. The plant is now operated by United States Enrichment Corporation, a subsidiary of USEC Incorporated, a publicly traded corporation (NYSE: USU). It was the only operating uranium enrichment facility in the United States in the period 2001–2010. The Paducah plant produced low-enriched uranium, originally as feedstock for military reactors and weapons refining and later for nuclear power fuel. The gaseous diffusion plant covers of a site. The four process buildings cover , and consume a peak electrical demand of 3,040 megawatts.〔(【引用サイトリンク】url=http://www.usec.com/gaseousdiffusion_pad_facts.htm )〕 ==History== The former Kentucky Ordnance Works site was chosen from a candidate list of eight sites in 1950. The construction contractor was F.H. McGraw of Hartford, Connecticut and the operating company was Union Carbide. The plant was opened in 1952 as a government-owned, contractor-operated facility producing enriched uranium to fuel military reactors and for use in nuclear weapons. The mode of enrichment was the gaseous diffusion of uranium hexaflouride to separate the lighter fissile isotope U-235 from the heavier non-fissile isotope U-238. The Paducah plant originally produced low-enriched uranium which was further refined at Portsmouth and the K-25 plant at Oak Ridge, Tennessee. From the 1960s the Portsmouth and Paducah plants were dedicated to uranium enrichment for nuclear power plants. In 1984 the operating contract was assumed by Martin Marietta Energy Systems. Lockheed Martin has operated the plant since the merger of Martin Marietta with Lockheed in 1995. From 2001, all USEC production has been consolidated at Paducah.〔(【引用サイトリンク】url=http://www.usec.com/gaseousdiffusion_pad_overview.htm )〕〔(【引用サイトリンク】url=http://www.usec.com/gaseousdiffusion_pad_history.htm )〕 The Paducah plant had a capacity of 11.3 million separative work units per year (SWU/year) in 1984. 1812 stages were located in five buildings: C-310 with 60 stages, C-331 with 400 stages, C-333 with 480 stages, C-335 with 400 stages and C-337 with 472 stages. Before its downsizing and final cessation of uranium enrichment on May 31, 2013, the Paducah facility consumed about 3,000 megawatts of electricity at peak operation. Power for the Paducah gaseous diffusion plant came from the Tennessee Valley Authority (TVA). In 2012 the majority of the TVA grid was generated by coal fired plants, with three nuclear power plants counting for about 30 percent of TVA's energy. Geoffrey Sea of "Neighbors for an Ohio Valley Alternative" wrote a series of articles on USEC for the ''Ecowatch'' news site. Although in 1996 the National Academy of Sciences estimated that total costs of gaseous diffusion cleanup ranged from $8 billion to $46 billion, it was reported that USEC plant's decontamination and decommissioning (D&D) fund was diverted and the surcharge was waived. The reporter further asserted that USEC had threatened the Department of Energy with "a sudden shutoff of power at Paducah at the end of May (2013)" despite its charter "to return the facility to DOE 'in safe condition.'" In May 2013, Paducah mayor Gayle Kaler said "Our priority as a community is first and foremost demanding cleanup dollars. We cannot accept a dirty shut down." It should be noted that the Paducah Gaseous Diffusion Plant is located outside the city of Paducah. When USEC ceased enrichment operations at its Portsmouth gaseous diffusion plant in Piketon, Ohio in May 2001, it reportedly did not purge the diffusion cells although it had nine years time and had received the funding. In late May 2013 the reporter predicted a dirty power down at Paducah. As of late June 2013, it was reported that USEC had shut down about 60 percent of the cascade, with the remainder to be shut down over the summer. On November 17, 2013 a tornado damaged the Paducah gaseous diffusion plant. A spokesman for the plant operator, USEC Inc., reported that damage was limited to the exterior of one of the four enrichment production buildings, adjacent cooling towers and an electrical switch yard. The spokesman stated that there was no release of hazardous or radioactive materials. In the previous year, on March 2, 2012 the "Camp Creek tornado" reportedly stopped a few miles short of the Piketon, Ohio plant.〔 Geoffrey Sea wrote in September 2013, USEC's demise will be either by creditors (by October 2014 loan repayment deadline), "regulators who find their spines", or by "repeal of the USEC Privatization Act by Congress."〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Paducah Gaseous Diffusion Plant」の詳細全文を読む スポンサード リンク
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