New water leak found at Japan nuclear reactor
Date: 12-Nov-01
Country: JAPAN
Author: Masayuki Kitano
The water leak, which amounted to about a drip of water every few seconds, was found last week at Chubu Electric's 540,000 kilowatt No.1 reactor at its Hamaoka nuclear plant during an inspection, they said.
The Hamaoka nuclear plant in Shizuoka prefecture, central Japan, had been shut down after emergency alarms sounded on Wednesday. A leak of steam containing a small amount of radiation was later confirmed.
An official at the Nuclear and Industrial Safety Agency, a government agency under the Ministry of International Trade and Industry (METI), said the water that was found leaking last week also contained radiation.
But he said the water leak did not pose a threat to people.
"It is a leak from inside the nuclear reactor...and the water does contain radiation," said Hiromitsu Yoneyama, an official at the Nuclear and Industrial Safety Agency.
"But it is not the type of leak that has the possibility of exposing people to radiation," said Yoneyama, adding that the water leak was discovered inside a container that houses the nuclear reactor.
"Such containers are built taking into account the possibility of leaks," he said.
The exact location of the leak and the cause would have to be confirmed through an inspection, which is expected to be completed later on the weekend, Yoneyama said.
SEPARATE INCIDENTS
Atsushi Sato, a Hamaoka nuclear plant official who was visiting Chubu Electric's Tokyo head office, said the water leak is believed to be unrelated to the steam leak accident.
"We think they are separate incidents," Sato said.
And the discovery of the water leak is unlikely to affect METI's tentative classification of the steam leak accident, the Nuclear and Industrial Safety Agency's Yoneyama said.
"I think a change can be practically ruled out," he said.
METI has tentatively classified the steam leak accident as "Level one" on the International Nuclear Event Scale, the first such designation for an accident at a Japanese nuclear facility since July 1999, when coolant water leaked at nuclear power plant in Fukui prefecture, 320 km (200 miles) west of Tokyo.
The scale, introduced in 1992 to classify nuclear accidents, goes from zero to seven, with seven being the most severe.
Japan's worst nuclear accident, which occurred in September 1999 at a uranium processing plant in Tokaimura, northeast of Tokyo, was designated "Level four".
Hundreds of Tokaimura residents, plant workers and emergency personnel were exposed to radiation when an uncontrolled nuclear chain reaction was triggered at the plant. Two workers later died.
Japan, heavily reliant on nuclear power, has seen a number of accidents over the past decade that have undermined public support for its nuclear programme, which meets a third of the country's electricity needs.
