JAEA head resigns following Monju lapses

Japan Atomic Energy Agency (JAEA) president Atsuyuki Suzuki has resigned after the country's nuclear regulator blocked the restart of the Monju prototype fast breeder reactor due to inspection deficiencies.

Japan Atomic Energy Agency (JAEA) president Atsuyuki Suzuki has resigned after the country's nuclear regulator blocked the restart of the Monju prototype fast breeder reactor (FBR) due to inspection deficiencies.

Monju (Image: JAEA)

The Nuclear Regulation Authority (NRA) said on 15 May that JAEA would not be permitted to make preparations for the restart of the 280 MWe Monju FBR until it could confirm improvements to its inspection procedures. The reactor has been offline since August 2010.

In November 2012 it was revealed that JAEA had failed to conduct regular inspections on almost 10,000 out of a total 39,000 pieces of equipment at Monju. Some of these included safety-critical equipment. In January, the NRA ordered JAEA to change its maintenance rules and inspection plans.

However, in a review of JAEA's performance since then, the NRA has found that the agency has failed to formulate and adhere to a strict inspection schedule. The regulator has given JAEA until 23 May to present evidence that refutes it findings.

JAEA president Suzuki submitted his resignation to minister of education, culture, sports, science and technology Hirofumi Shimomura on 16 May. The minister was quoted by the Asahi Shimbun newspaper as saying, "Based on the NRA's strict evaluations and the education ministry's demand for (sufficient safety) measures, the (JAEA) president considered his options seriously and concluded that he should resign. We decided to take the conclusion seriously and accept (his letter of resignation)."

Executive vice president Yonezo Tsujikura will be the acting head of JAEA until the new president is appointed, the agency said.

JAEA said in a statement that it will "devote its utmost effort to all of its missions, including the activities related to Monju, so as to restore the confidence of the public."

Monju's troubled past

A key part of Japan's nuclear energy program, Monju initially started in August 1995, but was shut down only four months later after a serious incident. About 700 kilograms of liquid sodium leaked from the secondary cooling loop and, although there were no injuries and no radioactivity escaped plant buildings, this was compounded by operator attempts to cover up the scale of the damage.

Monju was allowed to restart in May 2010 after JAEA carried out a thorough review of the design of the plant, as well as safety procedures, which were shown to have been inadequate. However, the reactor's operation was again suspended in August 2010 after a fuel handling machine was accidentally dropped in the reactor during a refuelling outage. The device was eventually retrieved almost one year later.

The prototype reactor uses plutonium fuel instead of conventional uranium and is configured to produce fissile matter that can be reused as fuel, hence the term 'breeder'.

Researched and written
by World Nuclear News