Tokai-mura reprocessing plant head-end to be shut down

Shaun Burnie with Mycle Schneider

In what appears at first sight to be a historic decision, the Japan Atomic Energy Agency (JAEA) announced 29 September 2014 that it will permanently shut down the head-end of the Tokai-mura reprocessing plant in Ibaraki Prefecture, Japan. A decommissioning plan is to be developed as early as 2015.

The plant operated from 1981-2006 when it completed the reprocessing of commercial spent fuel. JAEA had proposed that the plant continue operation by "testing" reprocessing of high burn up fuel, Mixed Oxide fuel (MOX) and fuel from the shut down Fugen Advanced Thermal Reactor (ATR). However, the decision to close the plant was prompted by cost estimates in excess of Y100 billion ($915 million) that would be required to bring the plant into line with post Fukushima-Daiichi regulatory guidelines.

Though a decision has been made to shut down the plant, the processing of uranium and plutonium solutions which are currently in the plant, and vitrification of resulting high level wastes will continue for the next 20 years, according to the JAEA. The JAEA indicated that the controversial Recycle Equipment Test Facility (RETF) at Tokai-mura will be used to insert the vitrified waste into canisters for transportation to as yet undetermined final disposal site. The RETF was originally designed to reprocessing spent and blanket fuel from the Monju fast breeder reactor. Twenty years ago it was revealed that the U.S. Department of Energy had transferred sensitive nuclear technology (SNT) for use in the RETF, a transfer not permitted under the 1988 U.S. Japan Peaceful Nuclear Cooperation Agreement.

Japan's Atomic Energy Commission (AEC) annual plutonium report in September 2013, declared a total of 668 kg in plutonium nitrate solution at the Tokai-mura plant, and a total of 83 kg of separated plutonium oxide, as of December 2012. An additional 120 tons of spent fuel, including MOX fuel from Fugen, currently in storage at the site is likely to be shipped overseas for reprocessing according to JAEA (reported by World Nuclear News). While no details were provided, the leading candidate would likely be the AREVA plant at La Hague.

The Tokai-mura plant has reprocessed a total of about 1140 tons of spent fuel comprising 82 tons of uranium fuel and 29 tons of MOX fuel from the Fugen ATR, 644 tons of boiling water reactor fuel, 376 tons of pressurized water reactor fuel and 9 tons of fuel from the Japan Power Demonstration Reactor (JPDR). With the closure of Tokai, the option exists for reprocessing of future Monju fast breeder reactor spent fuel in the small scale Chemical Reprocessing Facility (CRF). The throughput capacity of the CRF remains unclear though.

Operation of Japan's nuclear fuel chain facilities, including the processing of solutions and vitrification at the Tokai reprocessing plant, remain suspended pending compliance with Nuclear Regulation Authority (NRA) post-Fukushima Guidelines. As of 3 October 2014, JAEA had yet to submit an application to the NRA for review of the Tokai plant.

The decision to operate the Tokai-mura reprocessing plant was one of the most controversial issues in post war U.S.-Japan diplomatic relations. The Carter administration opposed Tokai-mura on nuclear non-proliferation grounds; at the time the United States was the major supplier of nuclear technology and fuel to Japan. Under the bilateral 1968 Agreement of Cooperation Concerning Civil Uses of Atomic Energy the U.S. held a veto right over reprocessing in Japan. The plant was designed by Saint Gobain Nucléaire (SGN), a subsidiary of COGEMA (now AREVA NC). In 2013, SGN was absorbed into the AREVA group. The non-proliferation argument was rejected by successive Japanese governments through the 1970s. The government of Prime Minister Fukuda described the operation of the plant as a "life or death" issue for Japan; and the U.S. State Department considered that failure to reach agreement would have profoundly adverse effects on bilateral relations. The Carter administration finally abandoned its opposition and the first testing of fuel began in 1977. The acceptable compromise involved limiting reprocessing to an initial batch of 70 tons, and testing co-processing techniques. In the end the Tokai plant, which had an original design throughput of 210 tons, reprocessed on average 42 tons of spent fuel each year.

Tokai-mura became known worldwide in 1999, when a criticality accident occurred at the JCO fuel fabrication facility, that led to two fatalities, radiation exposure to over 600 workers and members of the public and a significant traumatization of the local population. The announcement of the close of the Tokai-mura reprocessing head-end comes one day prior to the 15th anniversary of the 1999 accident. Former Tokai-mura mayor Tatsuya Murakami stated at a public meeting gathering of 350 people that "Japan was caught in a 'safety myth' that a serious nuclear accident would not happen in this country when the criticality accident occurred".

Earlier in September 2014, it was reported that Japan Nuclear Fuel Limited (JNFL) would likely postpone commercial operation of the Rokkasho-mura reprocessing plant for 18 months.