Rokkasho
Rokkasho Reprocessing Plant
A commercial-size reprocessing plant has been under construction since 1993 at Rokkasho in Aomori prefecture. The aggregate amount of plutonium to be recovered under existing agreements with overseas reprocessing facilities is estimated at approximately 30 tons. Domestically, upon the start of full-scale operation at the Rokkasho Reprocessing Plant, a little less than 5 tons of plutonium will be recovered annually.
The Rokkasho Reprocessing Plant [RRP] will have a capacity to reprocess 800 tonnes of spent fuel a year, with the spent nuclear-power reactor fuel having an average total plutonium content of up to 0.9 per cent.
Japan Nuclear Fuel Limited is promoting four fuel-cycle businesses--spent fuel reprocessing, high-level radioactive waste interim storage, uranium enrichment, and low-level radioactive waste underground disposal--in Rokkasho-mura in Aomori Prefecture. These businesses are operating with the understanding and cooperation of the local citizens. The ultimate aim is to establish a nuclear fuel cycle in which uranium fuel can be used repeatedly.
JNFL's nuclear fuel reprocessing plant is built with the best available Japanese and foreign technologies, including technologies imported from Britain and France, two countries with rich experience in the operations of commercial spent fuel reprocessing facilities. The reprocessing plant has a maximum preprocessing capacity of 800 tons annually. This is equivalent to the capacity to reprocess spent fuel from 30 one-million-kW class nuclear power plants. Uranium and plutonium recovered from the reprocessing of spent fuel are recycled as quasi-home-grown energy.
In July 1984 the Federation of Electric Power Companies asked Aomori Prefecture and Rokkasho-mura Village for permission to locate nuclear facilities in the village. In April 1985 a basic agreement on the siting of nuclear facilities was concluded. In March 1995 the High-Level Radioactive Waste Storage Center went into operation, and in December 1999 the reprocessing business started.
In October 1998 spent fuel from a light-water-reactor power reactor was transported for the first time to the reprocessing plant under construction in Rokkasho Village, Aomori Prefecture. The spent fuel consisted of 44 fuel assemblies (about 8 tons) from the Fukushima Dai-ni Nuclear Power Plant No.4 Unit (Fukushima Prefecture), the Tokyo Electric Power Co., Inc. These fuel assemblies left the port of the above-mentioned power plant aboard a specialized transport vessel "Rokuei-maru" (which displaces about 5,000 tons) in the morning of 01 October 1998, entered Mutsu Ogawara Port early in the morning of 02 October and were transported into the storage pool of the reprocessing plant of the Japan Nuclear Fuel Ltd. about 7 km away from the port on the evening of the same day.
On 26 April 1999 the Nuclear Fuel Ltd.(JNFL) announced a change in the completion date of its reprocessing plant under construction at Rokkasho in Aomori Prefecture. The completion date was changed from January 2003 to July 2005. The change was due to the following reasons: (1) The estimate of the required construction time due to design changes was insufficient; (2) Evaluation and review activities, which were initially unable to be predicted, were added; (3) Sufficient hours were allowed to conduct a test run step by step. JNFL also announced that the construction cost would be changed from 1,880 billion yen to 2,140 billion yen, based on a review reflecting the past construction contract status as well as the effects of changes of the construction process on the cost.
The Rokkasho Reprocessing Plant is steadily accepting spent fuel at its Spent Fuel Storage Facility and is promoting the construction of additional key reprocessing facilities with an eye to complete them in July 2005.
During 2002, the development and implementation of a safeguards approach for the Rokkasho Reprocessing Plant in Japan proceeded according to schedule. Major accomplishments included: installation of the On-Site Laboratory infrastructure, including cells, glove boxes and utilities; development and installation of the solution measurement and monitoring system; development of a software design for the data collection and evaluation system; and design information verification during the construction phase.
COGEMA provides operating experience and technological information to help ensure a smooth start-up to operations at the Rokkasho Reprocessing Plant. COGEMA personnel will be based at the plant, where they will liaise with, and provide technical assistance to, on-site JNFL personnel. BNFL Instruments has supplied a state-of-the-art waste drum assay system (WDAS) to Japan Nuclear Fuel Limited (JNFL) for use at the Rokkasho Reprocessing Plant. The system measures and characterises the plutonium content of 200 litre (55 gallon) plutonium waste drums with very high accuracy and rapidity using passive neutron multiplicity counting combined with advanced waste matrix correction techniques and high resolution gamma spectroscopy.
Preparatory arrangements are under way for the construction of the uranium-plutonium mixed oxide fuel (MOX fuel) fabrication plant in Rokkasho-mura village.
Vitrified Waste Storage Center
The Vitrified Waste Storage Center is a facility designed to safely store and manage vitrified waste packages returned from France and Britain for 30 to 50 years until those packages are ultimately disposed of. Radioactive substances in liquid waste which is a by-product of fuel reprocessing, is mixed with molten glass, sealed, and solidified in special containers. The resultant vitrified waste is then packed in canister, which are transported by sea to the site. On shore the vitrified waste canisters are inspected and measured to confirm that they can be stored and managed safely. Finally, the canisters containing the vitrified waste are stored in the repository. The vitrified Waste Storage Center now has the capacity to store 1,440 canisters; however, the center will be expanded in the future and will ultimately have a storage capacity of approximately to be capable of storing more than 3,000 radioactive waste canisters.
As of the end of February 2001, JNFL has received 464 canisters of vitrified waste returned to Japan after reprocessing overseas. Based on the future schedule for the return of vitrified waste, second-phase construction will be performed to create additional facilities in the Vitrified Waste Storage Building, thereby expanding the capacity of the existing first-phase facilities, which are expected to reach maximum capacity in FY2005.
Rokkasho Uranium Enrichment Plant
The Rokkasho Uranium Enrichment Plant is a centrifuge plant owned and paid for by JNFL. The plant has been operating since 1992, with an initial production capacity of 600 metric tons (MT) SWU (Separative Work Unit, used to state the quantity of uranium-enrichment services) per year. The plant was expanded to 1,050 ton SWU in 1999, with plans to expand to 1,500 ton SWU by 2005, which are about 30% of the needs of Japanese reactors. The JNFL's costs are some 20% or more above Russian and Western European prices. Japan's centrifuges are rather simple, with rotors made of maraging steel and with one unit per centrifuge.
