Oct 28 (NHK) - Japan's nuclear regulator says a massive number of pumice stones drifting in waters in the country's southwest could affect domestic nuclear power plants.
Ishiwatari Akira, a member of the Nuclear Regulation Authority, told a regular meeting on Wednesday that the stones may affect the intake of water used for cooling nuclear reactors.
The pumice stones are being washed ashore on the coast of Okinawa Prefecture and the Amami region of Kagoshima Prefecture. They come from an undersea volcanic eruption near the Ogasawara island chain in the Pacific Ocean in August.
Ishiwatari said the stones will likely come to Japan's main island of Honshu and called on officials to be prepared.
The authority says accumulated pumice and other objects may clog up the seawater intake equipment for cooling nuclear reactors.
It plans to assess the impact of the stones as the situation develops, and see how it is being addressed by the operators of nuclear power plants.
Officials of the Nuclear Regulation Authority had earlier taken up the impact of pumice stones when they discussed overall impacts of volcanos on nuclear power plants.
They say one of the effective ways to get rid of pumice is the measure being taken at each plant to remove jellyfish in the event of a plague. They also say installing fences in front of the water intake equipment can work.
