Govt must present clear road map for final disposal

How will soil contaminated by the accident at Tokyo Electric Power Company Holdings Inc.’s Fukushima No. 1 nuclear power plant be disposed of? The central government must expedite studies and research to select a final disposal site and establish disposal methods.

By the end of March, work to bring contaminated soil stripped away during decontamination work in Fukushima Prefecture into an interim storage facility straddling the towns of Okuma and Futaba in the prefecture was almost complete.

About 14 million cubic meters of contaminated soil, equivalent to 11 Tokyo Domes, has been collected so far. After the quantity was reduced by incineration and other means, about 12 million cubic meters were transported to the facility.

Years earlier, the soil had been put into large flexible container bags temporarily placed at school grounds, residential yards and elsewhere, but that material will now be managed collectively at the facility. This can be said to represent a step forward toward final disposal.

The interim storage facility has always been intended as a temporary repository. The local governments accepted the facility on the condition that the contaminated soil be stored there for up to 30 years before final disposal outside the prefecture. Final disposal by 2045 is required by law.

The central government said it intends to consider what form the final disposal site will take, and to begin selecting a candidate location for the final disposal in fiscal 2025 or later.

However, it must be said that the road ahead is difficult. Of the contaminated soil brought into the interim storage facility, 25% has relatively high radiation levels, so it cannot be reused for civil engineering work or other purposes. Nor is it guaranteed that any local government will accept the construction of a final disposal site.

According to an Environment Ministry survey, only 20% of respondents from outside Fukushima Prefecture knew about the policy of final disposal outside Fukushima Prefecture. It is important for the central government to thoroughly inform the public of the current situation first and foremost in order to seek understanding for the acceptance of the final disposal site.

It is not practical to transfer all the contaminated soil from the interim storage facility to the final disposal site. Efforts to reduce the amount of contaminated soil are also essential.

Regarding contaminated soil with low levels of radiation, for example, the central government plans to reuse it through such measures as burying it deep as part of civil engineering projects. Technologies have also been developed to separate radioactive materials from soil by heat or chemical treatments.

It is hoped that the central government will continue to study ways to treat and reuse contaminated soil in cooperation with private companies and research institutes.

Yet there is deep-rooted opposition to the reuse of contaminated soil for civil engineering work and other purposes due to safety concerns. It is vital to disclose the data after confirming safety by studying environmental effects through repeated feasibility tests.

To solve these issues one by one, a schedule for work related to the disposal of the contaminated soil needs to be finalized as soon as possible. The central government should draw up a detailed timetable and clarify the path to the final disposal.

(From The Yomiuri Shimbun, April 20, 2022)