Status of Japan's MOX fuel program

Guest contribution by Aileen Mioko Smith

Japan's Shikoku Electric utility began commercial operation with MOX fuel on March 2nd. This makes its Ikata-3 PWR the second nuclear reactor in Japan to begin using MOX fuel as part of its normal operations. The first reactor, Genkai-3 PWR, operated by Kyushu Electric, was started with MOX fuel in its core in November 2009 and produced first electricity on 2 December 2009.

These operations make the beginning of the active phase of Japan's "pluthermal" program, which calls for using plutonium in light water reactors and plans to have 16-18 reactors using MOX by 2015. It is expected to consume up to 9 tonnes of reactor-grade plutonium a year. Two other utilities are expected to begin using MOX in their reactors in 2010 - Chubu Electric (in its Hamaoka-4 BWR unit) and Kansai Electric (in its Takahama-3 PWR unit).

The MOX fuel that is used at this phase of the program is manufactured by Areva at its MELOX plant. The fuel that is being loaded in reactors was delivered from France in a shipment that reached Japan in May 2009. It contained 24 assemblies for Ikata-3, 28 for Hamaoka-4, and 16 for Genkai-3. In addition, 60 MOX fuel assemblies were delivered for use in Tokyo Electric's Fukishima I-3 and Kashiwazaki-Kariwa-3 BWR units earlier, in 1999 and 2001, respectively. This fuel, manufactured by Belgonucleaire, is awaiting approval by local authorities. Another MELOX-manufactured fuel shipment is scheduled to leave France shortly, probably this March.

The program reached this point after a ten-year delay due to numerous technical problems, earthquake risk reassessments and citizen protests.

On 21 February 2010, citizens held a public meeting in Saga prefecture, where the Kyushu's Genkai nuclear power plant is located, to announce filing of a civil lawsuit against the company. The lawsuit is expected to be filed by Kyushu residents sometime in March 2010 and will seek to terminate the use of MOX fabricated by AREVA's MELOX plant. This lawsuit is a continuation of the citizen protest campaign that submitted over 460,000 signatures to the Saga prefecture legislature in September 2009, asking the prefecture to refuse MOX fuel use at the Genkai plant.

One of the concerns raised about the MOX fuel assemblies used in Genkai is that they may have quality problems similar to those that were discovered during an internal inspection conducted by Nuclear Fuel Industries on behalf of the Kansai Electric utility in August 2009. As a result of that inspection, Kansai Electric had rejected one-quarter of the fuel that had been manufactured for use in its Takahama-3 and -4 reactors.

In early October 2009, Nuclear and Industrial Safety Agency (NISA) had stated that it couldn't rule out the possibility that the Genkai MOX fuel batch may have assemblies with similar problems. Kyushu Electric claimed the MELOX operators had assured it that the Genkai fuel had no problems like the ones found in the fuel for Kansai Electric, but the utility admitted it was not shown hard data to substantiate that assertion.

In a related development, on 1 March 2010, environmental NGO Green Action and other citizen groups submitted a petition to the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) stating that the MOX fuel casks for the upcoming shipment of MOX fuel (12 assemblies for Kansai Electric's Takahama-4 and 20 assemblies for the second load at Genkai-3) do not meet MLIT standards. Last year, on 26 February, twenty Diet members signed an open letter addressing this concern. Signers include the current MLIT minister Seiji Maehara and two other Diet members now ministers.

Another utility to start MOX operations this year, Chubu Electric, also encountered problems. When Chubu Electric's 28 MOX fuel assemblies were examined upon arrival at the Hamaoka-4 reactor in Shizuoka Prefecture on 18 May 2009, it was discovered that the metal separators for three fuel assemblies had been dislocated during the shipment. It has not yet been revealed whether these assemblies suffered damage and whether or not they will be loaded into the reactor.

UPDATE 03/31/10: Areva and Hokkaido Electric signed a contract to supply MOX fuel for the Tomari-3 unit.