Japan's Environment Ministry says waste produced by decontamination work following the 2011 Fukushima Daiichi nuclear plant accident could leak at 12 locations in case of torrential rain.

The ministry checked all the sites where the waste is kept after 91 bags were swept into rivers in Fukushima and Tochigi prefectures last year due to downpours caused by Typhoon Hagibis.

Nine years after the Fukushima Daiichi nuclear accident, more than half of the waste created by decontamination work is still kept near residents' homes.

About 14 million cubic meters of soil and vegetation has been collected in clean-up operations in areas affected by the nuclear accident in Fukushima Prefecture, except for heavily contaminated off-limit areas.