核廃棄物処分 現実的なフィンランドの判断

The Yomiuri Shimbun
Finland’s decision on final disposal of spent nuclear fuel makes good sense
核廃棄物処分 現実的なフィンランドの判断

The recent decision by Finland may serve as a good guideline to countries that are racking their brains over how to dispose of high-level radioactive waste generated from nuclear power plants.

The Finnish government has granted a licence for the construction of a final disposal facility for spent nuclear fuel, first such action in the world. Posiva, an organization tasked with the construction project, will start building the facility by the end of next year, with the aim of starting operation in 2023.

As high-level radioactive waste releases intense radioactivity for a long period of time, a geological repository for burial deep underground is considered an ideal method of disposal.

The Finnish government’s decision is based on the view that an above-ground impact will be avoided almost permanently if a stable geological stratum at least 400 meters deep and not accessible to human development is chosen for burying the spent nuclear fuel and multiple safety measures are taken.

Finland, a front-runner in this field, faces the challenge of verifying this concept in its implementation.

Unlike Japan, Finland plans to bury the spent nuclear fuel directly without reprocessing it. In any case, a high degree of safety is required. Other countries will be watching whether the construction of the facility proceeds smoothly.

The country’s geopolitical situation is one reason behind the project’s approval.

Lacking in energy resources, Finland depends on nuclear power for 30 percent of its electricity. Finland used to transfer spent nuclear fuel to Russia, its neighbor, but considering international circumstances, the country cannot continue its dependence on Russia.

Level-headed talks needed

The Finnish government and the nuclear power industry started looking for a final disposal site in the 1980s. Based on data on geological strata, more than 100 candidate sites were chosen. Having won the local community’s agreement, the country’s parliament approved Olkiluoto for the final disposal facility in 2001.

Posiva, established by the nuclear power industry to construct the facility, has conducted studies on conditions of the geological strata and the groundwater since 2004 in an underground research facility called ONKALO in Olkiluoto.

Stable bedrock underlies the whole area and is believed to have remained stable for more than 1 billion years. But it is practically impossible to prove its stability far in the future.

The Finnish government has requested that Posiva proceed with the project in stages, and make efforts to improve the safety at every stage, based on information and knowledge collected at each phase.

In many countries, including Japan, there are such extreme views as that the construction of such a facility cannot be approved unless it is certain that it will remain safe permanently. In the United States, the selection of candidate sites for such a facility has come to a standstill, as the safety of sites for more than 1 million years ahead came to be seen as a problem.

In this respect, the Finnish government’s way of thinking can be considered realistic.

The local government accepted the idea of hosting the facility by attaching importance to job creation and tax revenue increases. Although a political party opposing nuclear power once joined a ruling coalition, the issue has not become a political football.

In Japan, the central government has failed to win approval from a local government and it has been unable to even collect detailed data on geological strata. In exploring a disposal site, level-headed discussion is important.

(From The Yomiuri Shimbun, Nov. 30, 2015)

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