Workers at the crippled Fukushima Dai-ichi nuclear power plant were evacuated when a small tsunami hit Japan after a powerful undersea quake yesterday, highlighting the continued threat to the area devastated by the 2011 quake-tsunami.
The Japan Meteorological Agency warned people to stay away from the Pacific coast for nearly two hours as the tsunami, which was recorded as being as high as 55cm in one place, rolled ashore.
Two workers who had been patrolling wells used to measure underground water at Fukushima sought higher ground after the tremors struck, an official with the plant’s operator, said Tokyo Electric Power Co (TEPCO), while adding there were no new problems at the facility.
“There were few workers on the waterfront as it was nighttime. There was no impact of the quake and tsunami on the plant,” he told local media.
Another nuclear plant, at Onagawa, was the site of the largest wave recorded — 55cm — but there were no problems reported there.
All of Japan’s 50 viable reactors are currently shut down.
The magnitude 7.1 quake struck at a shallow depth of 10km at 2:10am, just more than 300km southeast of Ishinomaki in Miyagi Prefecture, the US Geological Survey said.
The meteorological agency said the quake was an aftershock of the March 2011 tremor.
“We have lifted all tsunami alerts, but the sea level may continue to show small changes for half a day or so. Please be very careful when working by the sea,” Keiji Doi, director of the agency’s quake predictions, told an early morning news conference.
“There is the possibility that aftershocks with a magnitude of around 7 will occur once in a while,” he said.
The area affected largely overlapped with that hit by the March 2011 disaster when more than 18,000 people died after a towering tsunami crashed ashore following a magnitude 9 undersea quake.
In the town of Ofunato, a 20cm tsunami was logged just after 3am, while Ishinomaki, which was devastated in 2011, recorded a 30cm wave.
“We evacuated as a matter of precaution because the ground floor of our house was flooded in the tsunami two years ago,” Chimaki Hojyo, a 69-year-old housewife in Ofunato, told the Yomiuri Shimbun.
“This kind of tsunami will keep us worried,” she said.
Eastern Japan, a seismically active region, was struck by a magnitude 6.5 earthquake last month, causing tremors that were felt 600km away in Tokyo.
The 2011 quake-tsunami knocked out cooling systems at the Fukushima nuclear plant, sending reactors into meltdown and forcing mass evacuations.
The effects of that disaster — the world’s worst nuclear accident since Chernobyl 25 years earlier — are still being felt.
TEPCO is battling to clean up the mess at the plant where thousands of tonnes of radiation-contaminated water are being stored in tanks after being used to cool the reactors.