Japan's Ministry of Economy, Trade and Industry (Meti) on 28 July released a map identifying areas which are suitable for the disposal high-level radioactive waste pinpointing areas away from active geological fault lines, volcanoes, potential drilling sites such as around oil fields, or ground where temperatures are high.
The map identified some 70% of the country's land as suitable and will be used to determine locations where high-level waste (HLW) from used fuel reprocessing could be stored 300 metres underground, according to Hirokazu Kobayashi, director of radioactive waste management at Meti.
The map “is the first step on the long road toward disposing of the nation’s highly radioactive nuclear waste,” Meti minister Hiroshige Seko told reporters in Tokyo. Based on the map, the government is expected to ask municipalities to agree to researchers investigating areas that could host HLW disposal sites. However local resistance to the project is expected, given widespread public concerns over nuclear safety following the 2011 Fukushima nuclear disaster.
At the end of March, some 18,000 tonnes of used fuel was stored at nuclear power plant sites, and the amount is increasing. The national map showed that up to 900 of Japan’s 1,800 municipalities have coastal areas deemed "favourable” for HLW disposal. The government will store the vitrified waste in canisters for up to some 100,000 years until its radioactivity decreases. Even after reprocessing Japan will have to deal with about 25,000 such canisters.
The map, showing four different colours based on levels of the suitability of geological conditions, was posted on Japan's Nuclear Waste Management Organisation (Numo) website. Numo expects site selection to begin around 2025, with repository operation from about 2035. The JPY3,500bn cost will be met by funds paid to Numo accumulated at 0.2 yen/kWh from electric utilities. By 2015, JPY1,000bn had been collected.
Energy minister Hiroshige Seko said publishing the map was an "extremely important step toward the realisation of the final disposal but also the first step along a long road”. He sees the map as an opportunity to open communications with municipalities and to “earn the understanding of the public”.
Areas deemed unsuitable for a geological repository because of "presumed unfavourable characteristics" are coloured in orange and silver. Areas classified as possessing "relatively high potential" are light green. Other zones within 20km of a coastline are considered especially favourable regarding waste transportation and are coloured in a darker green.
Among the suitable sites are a part of Fukushima Prefecture, where reconstruction efforts are still underway following the 2011 earthquake and tsunami that led to the Fukushima disaster. But Seko said the government has no plans at this stage to burden the prefecture additionally with the issue of HLW disposal. He also indicated that Aomori Prefecture, which hosts Japan’s reprocessing facility, is exempt from the process because the prefectural government and state have agreed not to construct a nuclear waste disposal facility there.
The process to find local governments willing to host a final repository site began in 2002, but little progress was made due mainly to local opposition.
In 2015, the government decided to choose suitable candidate sites on scientific grounds without waiting for municipalities to offer to host a waste facility.
The government aims to construct a site that can house more than 40,000 canisters, with estimated costs amounting to JPY3,700bn ($33bn).