Apr 06, 2011
Several nuclear plants along Japan's north east coast have survived a 7.1-magnitudeaftershock, the largest since the devastating 9-magnitude quake and tsunami on 11 March.
In a news conference shortly after the quake, which struck at 11.32pm Japanese time, the Tokyo Electric Power Company said that there has been no further damage at its stricken Fukushima Dai-ichi plant, and all workers there were successfully evacuated.
The quake epicentre was 26 kilometres beneath the sea and some 66 kilometres east of Sendai, the city devastated a month ago. Warnings from Japan's meteorological agency of an impending tsunami 1 to 2 metres high were lifted around an hour later.
Although much of northeast Japan was in darkness through power failures and buildings shook violently in Tokyo, 265 kilometres to the south, early reports are that all vulnerable power stations survived. According to The Australian, the nearby Onagawa nuclear plant in Miyagi prefecture, shut down since the original quake, has lost external power to two of its three reactors, but is surviving on the sole remaining source. And Tohoku Electric's Higashi-Dori nuclear plant in Aomori prefecture in northern Honshu is using a backup generator after losing all external power.
Meanwhile at the Fukushima Dai-ichi plant, the centre of the nuclear drama with four of its six reactors still in trouble, work began yesterday to inject inert nitrogen gas into the primary reactor vessel of unit number 1, in order to prevent rising levels of hydrogen within the vessel from reacting with oxygen to cause an explosion.
Also, Tepco reports that the leak of radioactive water from reactor unit two appears to have been successfully plugged after an operation on Tuesday to inject fast-setting glass into the cable duct through which the radioactive water had been escaping to the sea.