The March 2011 meltdown at the Fukushima No. 1 nuclear power plant caused serious damage to forests in the surrounding areas. Even now, 11 years after the accident, little has been done to decontaminate them.
In some areas, projects are underway to restore the satoyama, areas of mountain forest maintained by residents of adjacent communities, but the airborne radiation levels in those areas are still not low enough that children can safely enter, according to a local community leader.
One such area is the Yamakiya district in the town of Kawamata, Fukushima Prefecture. Walking trails in the Daini Oyako no Mori forest are covered by snow, and sunny slopes are lined with zelkova trees.
Yellow and pink vinyl wrapped around the trees indicates the year they were planted by local elementary school students. At the end of March, it will be five years since the evacuation order for the Yamakiya district was lifted. But even now, the voices of children have not returned to the mountains.
In 2016, satoyama restoration projects were launched in the prefecture to improve the forest environment. Decontamination, reforestation and radiation monitoring were carried out in an integrated manner in the mountain and forest areas that had been used by residents.
The projects have been carried out based on the comprehensive forest restoration policy for Fukushima Prefecture, which was compiled jointly by the Reconstruction Agency, the Agriculture, Forestry and Fisheries Ministry and the Environment Ministry. A total of approximately 800 hectares in 14 municipalities were selected as model areas, including forest parks and walking trails, where fallen leaves and other sediment was removed and thinned.
The town and the local residents chose Daini Oyako no Mori as a site for the project in order to revive the area as a site where children could study forestry. The project was launched in December 2016, prior to the planned lifting of the evacuation order for Yamakiya district at the end of March 2017.
The project covers an area of about 2 hectares. In fiscal years 2016 and 2017, planted cedar and zelkova trees were thinned and cleared, and trees that had fallen due to snow were removed. Logs were spread on slopes as a measure to control topsoil runoff.
Decontamination work was conducted in fiscal 2018. Leaves and branches that had fallen to the ground and other accumulated organic matter were removed in areas covering 5,595 square meters of the forest, including an open square and walking trails. The zelkova trees could die if their surfaces were stripped, so the work focused on clearing the grass and thickets.
Comparing the radiation levels in September 2018, before the decontamination work, and in November the same year, after the work, the average radiation level in the open square had been reduced by 22%, to 0.69 microsievert per hour. Based on the result, the central government concluded that “the decontamination work contributed to creating an environment ready for the resumption of forest study activities.”
However, even after the decontamination process, the airborne radiation levels were far from the central government’s long-term target of 0.23 microsieverts per hour. At some monitoring points, radiation levels exceeded 1 microsievert per hour.
“The area is not ready for children to go back,” said Toshio Hirono, 71, leader of the Yamakiya Elementary School’s forestry club.
Residents are demanding that the forest, where children once enjoyed the greenery, be restored to its original state.
“If it hadn’t been for the nuclear accident, there would have been so much more I wanted to do,” said Hirono.
Hirono has been serving as the third leader of the group for about 20 years, without a chance to pass on his position to a successor due to the suspension of its activities. He feels that although Daini Oyako no Mori has been decontaminated, the level of radiation has not gone down enough.
“If there is even a slight concern, we cannot allow our children to go into the mountains,” he said with a sigh.
Even after the model project ended, Hirono continues to voluntarily clear the undergrowth along the walking trails every fall. He understands that decontaminating all the forests in the town will not be easy, but believes that unless the radiation levels in the surrounding areas of Daini Oyako no Mori are lowered, residents will not be reassured.
“It is the central government’s responsibility to decontaminate until the residents are satisfied,” he said.