Tokyo Electric Power Co. said it will install water level gauges on all flange-type tanks storing radioactive coolant at the Fukushima No. 1 nuclear plant by the end of November, to enhance monitoring.
Last month, Tepco belatedly revealed that one of the tanks, which number in the hundreds and are made of steel plates bolted together, leaked 300 tons of highly radioactive water, causing a domestic and international uproar over the environmental contamination.
The company’s announcement Friday about the gauges came after it admitted Thursday that the water probably seeped down through the plant’s wrecked reactor buildings and merged with tainted groundwater flowing into the Pacific.
The new gauges can remotely monitor the levels of water in the tanks nonstop and sound an alarm if a decrease is detected, Tepco said.
Currently, only 55 flange-type tanks out of 337 are equipped with gauges. The existing devices differ from the ones that will be installed and cannot be remotely monitored.
The storage tanks, which are considered temporary, are sealed with waterproof packing at their bolted-together seams. Several leaks of radioactive water have occurred, including the 300 tons that flowed into the sea recently.
The Nuclear Regulation Authority deemed that leak a level 3 “serious incident” on the International Nuclear and Radiological Event Scale. The March 2011 triple meltdowns at the Fukushima No. 1 plant were designated a level 7 incident, the highest level, just like the 1986 Chernobyl catastrophe.
The leak of radioactive water has drawn much international scrutiny, in part because the International Olympics Committee was scheduled to decide early Sunday Japan time whether Tokyo, Madrid or Istanbul will host the 2020 Summer Olympics.
During a news conference in Buenos Aires on Wednesday, where the IOC will announce the host city, many questions from foreign media to officials representing Tokyo’s bid focused on the Fukushima plant.
In an apparent effort to deflect the concerns, Tepco on Thursday posted a video message by President Naomi Hirose on its English-language website.
“We recognize that bringing the contaminated water under control is the most urgent and serious problem that must be addressed. We are tackling this by implementing not only emergency measures, but also fundamental measures,” Hirose said in the message.
He also said the radiation monitoring shows that the impact has been contained within the small, now basically walled-in harbor at the plant, and that the wider ocean is safe.