Nine Japanese power utilities owning nuclear power plants and specialised nuclear power generator Japan Atomic Power Co (Japco) told the government on 20 November that they plan to increase their total storage capacity for used nuclear fuel by 6000t from the current level by around 2030 to avoid any shortage of storage facilities.

Some facilities are almost full, with some 70% of their current total capacity of 20,670t already used. Reactor operators hope the capacity increase will encourage restarts of nuclear reactors idled after the March 2011 Fukushima Daiichi accident.

Kansai Electric Power Co unveiled its plan to start operating a facility with a storage capacity of some 2000t around 2030 although it has yet to decide on a location. The company aims to take the decision around 2020, looking to select a site outside the central Japan prefecture of Fukui, where its nuclear power plants are located.

Tokyo Electric Power Co (Tepco) and Japco have mapped out a plan to secure a storage capacity of 3000t in Mutsu, Aomori Prefecture, northern Japan, during fiscal 2016, which starts in April. The power utilities will also consider the possibility of joint construction of facilities.

Meanwhile, completion of Japan's Rokkasho reprocessing plant and mixed-oxide (mox) fuel factory have been postponed by around two years as work continues to comply with new safety requirements. Japan Nuclear Fuels Ltd (JNFL) said Rokkasho would be complete in mid-2018 instead of early 2016, while the Mox plant will be complete in mid-2019 instead of late 2017.

Together the facilities will store used fuel from Japanese nuclear plants before separating it into one stream of waste for disposal and another stream of uranium and plutonium for recycling in new Mox fuel assemblies. This work has previously been carried out for Japan at reprocessing facilities in France and the UK.

JNFL said the reprocessing plant needs a new emergency response centre twice as large as the one that was completed around the time of Fukushima, and the new building will need to be anchored to the bedrock. In addition, a water storage tank, built before the new regulations came into force, must be retrofitted with anchors to secure it to the bedrock. A large amount of piping must also be upgraded to higher seismic standards. All this will take another 2.5 years for the reprocessing plant and 3.5 years for the Mox plant,JNFL said, based on the current rate of progress in agreeing changes with regulators.

The post-Fukushima regulations mean Rokkasho must be ready to withstand the effects of earthquakes five times bigger than before (magnitude 9.0 instead of magnitude 8.3) and oceanic earthquakes 1.5 times bigger (magnitude 7.4 instead of 7.2).

However, the plant had faced a series of delays long before Fukushima. It was originally scheduled for start up in 2000, and was most recently set to open next March following a series of technical problems. JNFL President Kenji Kudo told reporters that a separate plant to produce plutonium-based fuel had been delayed until sometime during the first half of fiscal 2019.

Japan already has about 47t of plutonium - 11t at home and the rest reprocessed in Britain and France - but has no use for it, with most of its reactor fleet offline since 2011. Moreover, only ten of Japan's plants are licensed to use Mox.

Date: Monday, 23 November 2015
Original article: neimagazine.com/news/newsmore-storage-needed-for-japans-used-fuel-4734761