Japan’s long-delayed nuclear fuel reprocessing plant at Rokkasho in Aomori Prefecture formally passed safety checks on 29 July. The plant, operated by Japan Nuclear Fuel Ltd (JNFL), cleared the more stringent safety standards introduced in the wake of the 2011 Fukushima nuclear crisis, including more robust measures against earthquakes and tsunami. However, JNFL still needs to obtain approval for a construction plan, including a detailed design description of the facility’s equipment, in order to start operations.

It is unclear whether the company will be able to complete all necessary procedures for the facility in the first half of fiscal 2021 as planned.

The plant is key to the government’s plans for nuclear fuel recycling but the its future is unclear following the decommissioning of the Monju fast-breeder reactor in Fukui Prefecture that was to have used mixed-oxide (mox) fuel produced by the Rokkasho plant and the limited number of reactors in operation which use mox. The Monju reactor had experienced  a series of problems including a leakage of sodium coolant in 1995.

Japan currently has over 40 tons of plutonium stockpiled as a result, raising international concerns about the country’s possession of the material, which can be converted into nuclear weapons. If it opens, the plant will be able to take up to 800 tons of used fuel a year and extract about 8 tons of plutonium, which will be used to produce mox. Meanwhile, there are approximately 3,000 tonnes of used nuclear fuel at Rokkasho and  the plant has been unable to accept any more for the past four years.

Construction of the plant began in 1993 and was scheduled to be completed by 1997, but persistent troubles forced the timeline to be pushed back 24 times. In 2017, it was discovered that the company failed to carry out necessary inspections on an area of the plant for 14 years, resulting in nearly a ton of rainwater pouring into a building housing an emergency diesel generator.

JNFL applied for the safety checks in January 2014, and the Nuclear Regulation Authority (NRA) approved its measures this May. NRA then sought feedback from the public and concerned parties prior to formal approval. The feedback was largely critical, with some saying the country’s nuclear fuel recycling policy is already deadlocked, according to the NRA’s secretariat. The total project cost of the Rokkasho plant, from construction to its eventual decommissioning, is estimated to be JPY13,900bn ($130 billion).